UMEÅ UNIVERSITY

Department of Public Health and Clinical Medicine

MASTER THESIS Heavy metal levels and nutritional status in two indigenous

communities of the Corrientes river- Loreto- Peru.

AUTHOR: Cynthia Anticona Huaynate

SUPERVISOR: Miguel San Sebastián

Umeå, 2008

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ABREVIATIONS

BLL Blood lead level

BTL Biological tolerance limit

CENSOPAS National Center for Occupational Health and Protection of the

Environment for Health (Centro Nacional de Salud Ocupacional y

Protección Ambiental para la Salud)

CDC United States Centers for Disease Control

DIGESA Peruvian government’s General Directorate for Environmental

Health (Dirección General de Salud Ambiental)

DIRESA Regional Directorate for Health (Dirección Regional de Salud)

EIA Environmental impact assessment

EPA United States Environmental Protection Agency

ERI EarthRights International

FECONACO Federation of Native Communities of the Corrientes River

(Federación de Comunidades Nativas del Río Corrientes)

HDI Human Development Index

HTO Hematocrit

IARC The International Agency for Research on Cancer

ICP Inductively Coupled Plasma

IIAP Institute for Research on the Peruvian Amazon (Instituto de

Investigaciones de la Amazonía Peruana)

INEI National Institute of Statistics and Information Technology

(Instituto Nacional de Estadística e Informática)

INRENA National Institute of Natural Resources (Instituto Nacional de

Recursos Naturales)

MINSA Ministry of Health (Ministerio de Salud)

NGO No governmental organization

OECD Organization for economic cooperation and development.

ONERN National Office of Natural Resource Evaluation (Oficina Nacional

de Evaluación de Recursos Naturales)

OXY Occidental Petroleum Company

PAH Polycyclic aromatic hydrocarbons

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PEPISCO Special Project for the Complete Health Plan of the Corrientes

Proyecto Especial Plan Integral de Salud del Corrientes

TPH Total petroleum hydrocarbons

UN United Nations

UNDP United Nations Development Programme

USAID United States Agency for International Development

WHO World Health Organization

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ABSTRACT

Background. Oil industry in the Corrientes river basin has more than 30 years of exploration and exploitation activities. Although numerous studies have analyzed the environmental impacts, scarce evaluations of health and social impacts have been performed. In 2005, the Peruvian government’s General Directorate for Environmental Health (DIGESA) carried out a survey in seven communities and reported high levels of lead and cadmium in blood samples. After one year, the Regional Directorate for Health (DIRESA) of Loreto attempted to assess the situation in all the Corrientes population and started a new evaluation in two communities, where data on nutrition and heavy metals was collected. Among other health problems, nutritional status seems to be substantially affected by the impacts of oil exploitation and high poverty levels. Coincidently, nutrition has been well studied for its relation with heavy metals poisoning.

Objectives. Taking into account previous evidence and in order to analyze available material, our aim is to investigate possible associations between heavy metal levels and nutritional status in this particular population.

Methodology. This cross sectional study analyzed data from the 2006 DIRESA surveillance, including 153 people of two indigenous communities (San Cristobal and Jose Olaya). Available data included demographic information, anthropometric measures (height and weight), hematocrit concentrations as well as blood lead, urinary cadmium and urinary mercury levels. Anthropometric measures were computed with Epiinfo and anemia status was determined using hematocrit concentrations. New data was entered in an excel file and analyzed in Stata version 10. Descriptive statistics, means comparison test and correlation test were used for the analysis in 3 different age groups. Simple regression analyses were performed to asses association between heavy metal levels and nutritional variables.

Results. Hematocrit levels showed a 73.4% prevalence of anemia in the total population. In population under 18 years, anthropometrics reflected 16.6% prevalence of underweight and 27.5% of stunting. In adults, BMI showed normal records in most population (68%) , almost no one had underweight, on the contrary 30% presented overweight/obesity. Neither anthropometric results nor anemia status displayed differences between sex. Height for age was significantly lower in the young group and BMI was inversely correlated with age.

Blood lead levels (BLL) above the recommended limit 10 ug/dl were found in 61% and 82 % of the 1-6 years group (mean: 10.2) , and 7- 17 years group (mean: 11.9) respectively, while 21% of the oldest group (18->) had BLL above 20 ug/dl (mean: 13.9). Significantly higher BLL were found in Jose Olaya than in San Cristobal. Age but no sex was correlated with BLL. In the same population, cadmium levels above the recommended limit of 0.8 ug/g creatinin were found in 56% of the 1-6 years group (mean: 1.4) 31% of the 7-17 years group (mean: 0.9) and in 55% of the adult group (mean: 1.5). Mercury levels above the recommended limit 1 ug/g creatinin were found in 27% of the 1-6 years group (mean: 1.6), 8% of the 7- 17 years group (mean: 1) and in 12.5% of the adult group. Neither urine

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cadmium nor mercury levels were correlated with sex, age or community. Linear regression analysis reflected no significant association either between BLL and anthropometric measures or between BLL and hematocrit concentrations in this study population.

Conclusions The nutritional status was characterized by a high prevalence of anemia in the total population, signs of chronic malnutrition affecting at least 30% of the children and adolescents and presence of obesity/overweight in a third part of the adult group. The means BLL were consistent with previously reported levels by DIGESA in 2005 in other 6 Achuar communities. No association was found between BLL and nutritional status in this study population. However, the cross sectional design could have significantly modified the present results. Given the moderate blood levels and relatively high cadmium levels, attempts to tackle the problem should focus in identifying the sources and develop preventive strategies.

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LIST OF CONTENTS I. INTRODUCTION ....................................................................................................................................... 7 

II. BACKGROUND ......................................................................................................................................... 8 

2.1. PERÚ ....................................................................................................................................................... 8 2.1.1. General information ....................................................................................................................... 8 2.1.2. Demographic information .............................................................................................................. 9 2.1.3. Socioeconomic information .......................................................................................................... 10 

2.2. OIL INDUSTRY IN PERÚ ........................................................................................................................ 11 2.2.1. HISTORY ............................................................................................................................................. 11 

2.2.3. Production ................................................................................................................................... 12 2.2.4. ECONOMICAL BENEFITS ...................................................................................................................... 12 2.3. ENVIRONMENTAL AND HEALTH IMPACTS OF OIL EXPLOTATION ............................................................ 13 

2.3.1. Oil production phases .................................................................................................................. 13 2.3.2. Environmental impacts ................................................................................................................ 14 2.3.3. Human health effects .................................................................................................................... 14 

2.4. PERUVIAN AMAZON AND OIL INDUSTRY ............................................................................................... 15 2.4.1. Amazon basin ............................................................................................................................... 15 2.4.2. Loreto region ............................................................................................................................... 16 2.4.3. Petroleum industry ....................................................................................................................... 17 

2.5. CORRIENTES RIVER BASIN..................................................................................................................... 17 2.5.1. Location ....................................................................................................................................... 17 2.5.2. Population .................................................................................................................................... 18 2.5.2.5 Health......................................................................................................................................... 19 2.5.3. Oil exploitation in the Corrientes river ........................................................................................ 20 2.5.4. Environmental impacts ............................................................................................................... 21 2.5.5. Health impacts ............................................................................................................................ 22 

III. JUSTIFICATION OF THE STUDY ..................................................................................................... 23 

IV. OBJECTIVES ......................................................................................................................................... 23 

3.1 OVERALL OBJECTIVE ...................................................................................................................... 23 3.2 SPECIFIC OBJECTIVES ..................................................................................................................... 23 

V. METHODS ................................................................................................................................................ 24 

VI. RESULTS ................................................................................................................................................ 28 

VII. DISCUSSION ......................................................................................................................................... 36 

VIII. CONCLUSSIONS ................................................................................................................................ 39 

IX. REFERENCES ........................................................................................................................................ 40 

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I. INTRODUCTION

The Corrientes river is placed in the Peruvian northeastern part of Peru, in Loreto Region. Its basin is home for a large number of plants, animal species; and more than 6000 indigenous people from Achuar, Quichua, and Urarina ethnic groups. But the Corrientes basin is not only treasured because of its ecological and cultural contribution to the country, but principally, for the numerous oil reserves which lie along its whole extension. Oil industry in the Corrientes has a 30 years history of exploration and exploitation activities, those which are linked to several environmental, social and health impacts. (La Torre, 1999) As it well known, environmental factors play an important role in population’s health, and this is more notorious when people’s source of sustainability is the environment as it is the case of all the native communities in the Corrientes. Unfortunately, no comprehensive health evaluation has been performed to measure the magnitude of the health impacts. Only two surveillances from 2005 and 2006 assessed some health parameters including nutritional status and heavy metal screening in the population of some Achuar communities. Their findings showed elevated lead and cadmium levels, which were ascribed to the interaction with the seriously contaminated environment. On the other hand, poor living conditions and limited access to essential micronutrients put Achuar people at a higher risk of being malnourished and suffering the adverse effects of many pollutants. (MINSA, 2006) Many authors have studied associations between heavy metals, especially lead, and altered nutritional indicators such as growth and development impairments, specific nutrients deficiency, among others. (Bradman et al, 2001; Elias et al., 2007; Frisancho et al., 1991; Kordas et al., 2009; Selevan et al., 2003, Wright et al., 2003). Although it is plausible that a deficient nutritional status could lead to higher lead and cadmium levels (Bradman et al, 2001) additional research is necessary to validate the current hypothesis. Thus, the present study aims to evaluate the relationship between three heavy metal levels (lead, cadmium and mercury) and the nutritional status of two Achuar communities, with an overall goal of providing insight into the effects of these metals exposure among a population already affected by environmental pollution, poverty, and other social deprivations. (MINSA, 2006)

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II. BACKGROUND

2.1. Perú

2.1.1. General information

Peru is located in the western South American Region. It shares its northern border with Ecuador and Colombia. Brazil is located to the East and Bolivia and Chile to the South. Finally, the Pacific Ocean meets its Western border. The country has a total area of 285,220 km², which is divided into three main geographical regions (the coastal, the highlands and the jungle region) and twenty-five sociopolitical regions, displayed in Figure 1. (INEI, 2006) Figure1. Sociopolitical map of Peru Because Peru is a multiethnic country, both Spanish and Quechua are recognized as official languages. However, there are several other native, indigenous languages that are spoken. (INEI, 2005) After many years of political and economic turmoil, Peru’s economy started to grow and recover from the depression and stagnant economic indicators of the late twentieth century (World Bank, 2006; Banco Central de Reserva, 2006) . The economical growth and the progress in curtailing guerrilla activity achieved by the former president Alberto Fujimori (1990–2000), was obscured by his questionable political practices which forced his resignation after the 2000 elections. Since then, Perú has tried to fight corruption and

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apparent democracy has set in. The current president Alan García has maintained Peru's economic stabilization, reduced liberalization trade program barriers and opened the economy to foreign investment, with the result that Peru now, has one of the most open investment regimes in the world. (Weisbrot, 2006) However, there are serious repercussions involved in this economic growth. Uncontrolled industries, such as the oil industry in the Amazon Region have been taking a high toll on human’s health and the country’s biodiversity.

2.1.2. Demographic information

Peru is a multiethnic nation constituted by the combination of different groups over five centuries. The largest segment of the population (45%) is represented by Amerindians or indigenous groups, which are dispersed throughout the country beyond the Andes Mountains and the Amazon region. Some examples of indigenous peoples residing in the Amazon basin include the Shipibo, Urarina, Aguaruna, and Achuar. According to the United Nations (UN, 2007), the rest of the population is grouped in mestizos (mixed Amerindian and white) 37%, white/Caucasians 15% (mostly of Spanish descent), black/Afro-Peruvian, Japanese, Chinese, and Arab/Middle-Eastern (although are white) 3%. Peruvian population is 28,302,603. The majority lives in the coastal areas and they are concentrated around the Peruvian capital city, Lima. While 50% of the total population lives in the coastal areas, 36% live in the country’s highlands and the remaining 12% are located in the Amazon region (INEI, 2006). Regarding Peru’s demographic profile, there has been a notorious decline in fertility and mortality since the mid-1970s. Statistics from 2006 (INEI, 2006) report a total fertility rate of 2.51 children born/woman and an infant mortality rate of 30.94 deaths/1,000 live births. Additionally, the crude birth rate was found to be three times higher than the crude death rate (20.48/1,000 and 6.23 /1,000 respectively) and the major age group was in the labor force age range (15 to 64) with 63.7% of the total population. Concerning education, information available for literacy rates (that date to 2004) shows a total literacy rate of 87.7% of which males have a 93.5% and females 82.1%. Regarding schooling rate, the situation seems to be optimistic; almost 100% of the children are enrolled in primary schools and 65% in secondary schools. However, the quality of education is considerable worrisome. From the international student evaluation programme, Peruvian’s score was the last within Latin America. For the Organization for Economic Cooperation and Development (OECD, 2005), just 5% of Peruvian students perform according to the average in the rest of the world. Within the country, there is a big gap between regional and urban-rural demographic variations. These variations reflect disparities in wealth, resources, and availability of government services. Access to basic services like potable water, sanitation and electricity, as well as health care services and education continues to be significantly better for urban than for rural people, and for the highest quintile in comparison to the last one. (UN, 2007). The United Nations Development Programme (UNDP, 2008) has calculated Peru’s Human Development Index (HDI) in 0.773. In relation to quality of basic education the World Economic Forum 2007 ranked Peru as number 95 out of 131 countries.

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2.1.3. Socioeconomic information

Peru’s economy is based on the exploitation, production and exportation of natural resources mainly from the mining, agricultural and fishing sectors. Since the early 50’s until de 70’s, economy was commanded by substituting importation policies, which never were effective and instead contributed to the great financial crisis of the late 80’s. The era of the open markets started in 1990 with Alberto Fujimori’s government, with the imposition of new laws, and policies to attract foreign investment. These reforms together with a supportive international conjuncture set the basis for the economic growth Peru has experienced in the last 5 years. In 2007, the GDP- per capita purchasing power parity ($7,600) grew in 9% and the exportations increased more than 35% (INEI, 2008). On the contrary, the external debt (28 billion, 2007 est.) was reduced to the 50 % in 2000 and to the 34% in 2006. Currently, the economic growth relies on a macroeconomic stability, the promoting system for trade and exportation, and the rise of investment and consumption. (Office of the United States Trade Representative, 2007) However, despite this apparent bonanza, the neoliberal policies lead to the bankrupt of many national enterprises while favoring to foreign capitals which enjoy taxes exonerations and scarcely invest their profits in the country. Moreover, the wealth being produced has not been equally distributed. In fact, 51.6% of the population is poor and 19.2% is extremely poor. (INEI, 2007) Poverty levels are significantly higher in rural areas, while urban areas—most notably metropolitan Lima—are the most unequal. Inequality, measured by the Gini coefficient, stands at 0.43, below the Latin America average of 0.52, but still high by international standards. (World Bank, 2007) The high poverty rates maybe, in part, due to the lack of human capital and initial support systems to provide employment. Statistics of 2004 calculated unemployment and underemployment indexes of 7.2% and 54%, respectively. The poorest departments in Peru are: Huancavelica, Ayacucho, Puno, Apurímac, Huánuco, Pasco, Cajamarca and Loreto. (World Bank, 2007) Loreto region’s poverty rate is significantly larger than the country’s average: 62.7% of the population is poor and 32% is extremely poor. However, the unemployment rate (2.73%) seems to be lower than the country’s average. (INEI, 2006) Peruvian’s gross domestic product ( $198.1 billion) is mainly accounted by services (53%), followed by manufacturing (22.3%), extractive industries (15%), and taxes (9.7%). (Banco Central de Reserva, 2007). As mentioned before, exportation is one of the Peruvian economy’s driver. The main exports are mining products (65%), diverse services (25%) agriculture (1.7%), fishery (5.4%) and oil (8.6%). While the most important trade partners are United States (30%), Mainland China (11%), Japan (6%) and Chile 5% (Banco Central de Reserva, 2007) Concerning hydrocarbon products, Peru is one of the countries that have significant reserves of oil and natural gas; these represent not only the dominant national fuel source but also an important export product.

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2.2. Oil industry in Perú 2.2.1. History

Oil is a strategic resource because it is the world’s principal source of energy, because it is a scarce, non – renewable resource, and because of the geographic locations of oil reserves on the planet. (La Torre, 2006) Oil industry in Peru started in 1863, when the first Peruvian well was drilled for petroleum. Well 4 was located in the Cruz Bay in the Tumbes region and became the first commercial well in South America. However, real oil industry in Peru was delayed until the 1970’s when the oil price boom shocked the whole world. In that context, the Peruvian Amazon region became a great territory for the petroleum exploitation operations, then, extraction, refining, and domestic marketing began to work under control of the Petroleum Enterprise of Peru (Petroleras de Perú--Petroperú). (Arriagada, 2006)

At first, the crude petroleum was transported by cargo ship to Iquitos but in 1977, the North Peruvian Oil Pipeline started functioning and the Terminal Bayovar was the first station in receiving crude oil directly pumped from Petroperu wells. After one year, the Ramal Norte pipeline started transporting the oil from the Andoas station to Station 5 in Loreto. (ERI, 2007)

The following years oil production followed the world trend without any remarkable fact. However, between 1990 and 1991, Alberto Fujimori’s government introduced several changes to promote international investment, which finished the monopoly position of Petroperú and opened the negotiations with many foreign oil companies to begin exploration activities. Between 2000 and 2005 many discoveries of oil reserves were announced by foreign companies, such as Occidental Petroleum in Block 64, and Petro-Tech in Block Z-2B. And in 2006 , 97 million acres of the Peruvian Amazon were already zoned for oil and gas exploration and exploitation. Today, Peru’s oil industry has 3 main areas for exploitation and production which are Talara (since the early 1900)– Marañon river basin, (since 1971) and Camisea (since 2004). However, the government has declared to have potential petroleum reserves, requiring more intense exploration activities. In that sense, current Peruvian policies and laws have been framed to promote concessions and international investment. (National Society of Mining, Petroleum and Energy, 2007) Nowadays, there are 39 active oil concessions for exploration activities and 18 of them are in charge of multinational companies from different countries: American Companies Occidental, ConocoPhillips, Barrett, Harken, Hunt, and Amareda Hess (United States), Pluspetrol (Argentina) , Perrobras (Brazil), Repsol from Spain, Petrolífera of Canada and Sipet of China are some examples. (Apoyos and asociados, 2006).

In April 2007, PerúPetro signed 61 contracts with international oil companies to explore and drill for petroleum. This contracts established total terms of 30 and 40 years for oil and gas exploration respectively, with seven year exploration phases of seismic studies and drilling of several exploratory wells. (Perúpetro, 2007)

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2.2.3. Production

There are approximately 40,000 oil fields in the world, but less than 5% of them contained 95 % of the total world oil reserves when first discovered. (Gilbert,1993). More than the half of oil production occurs in developing countries of the Middle East, Latin America and Africa. (La Torre, 1999). According to the World Energy Council (WEC), the oil reserves in Latin America represent 9% of the total in the world. (WEC, 2001) In Peru, oil production accounts for 78% of the consumed oil, while the 22% remaining is imported. (Perupetro, 2007) Oil production is concentrated in the northern part of the country. The largest oil blocks are Block 1-AB (Pluspetrol) along the border with Ecuador and Block 8 (Pluspetrol), in the northeastern Amazon region, representing 65 % of Peru's total crude oil production. But also Block X (Petrobras) in the northwest, and Block Z-2B (Petro-Tech Peruana) which is off the northwest coast. Other important wells are San Pedro 1X well in Block Z-2B (Petro- Tech) and Block Z-2B (Occidental Petroleum). Regarding the crude oil quality, its mostly a heavy, sour variety known as "Lorento," with 20° API and 1.2 % sulfur content. (Perupetro, 2007) According to Oil and Gas Journal (OGJ), Peru had 930 million barrels of proven oil reserves in 2007. The country produced 115,000 barrels per day (bbl/d) of total oil liquids in 2006, of which 67 % was crude oil. In recent years, the natural gas liquids production has represented the bulk of the increased oil production, as crude oil production has been in long-term decline for the last decade. The largest oil producer in Peru is Argentina-based Pluspetrol, which holds Pluspetrol Norte and Pluspetrol Peru Corp, accounting for 68% of the total oil production, then it comes Petrobras (11.7%) , Petro-Tech Peruana (10.4%) among others. (Petroperu 2007) The sole crude oil pipeline Norperuano is managed by the national enterprise. It has a maximum capacity of 250,000 bbl/d (Perupetro, 2007) and links the export station Terminal Bayovar to oil fields in Peru's interior. Its two branches departure one from the Ucayali basin, while the other from Andoas district in the Marañon basin. Both branches meet at a central pumping station, where they join into a 35-inch system that carries crude oil 340 miles to the Pacific coast. Peru has six major oil refineries, with total capacity of 192 950 bbl/d. However, the two largest are managed by foreign companies: La Pampilla with a capacity of 2 248 000 bbl/d is operated by Repsol-YPF and Pucallpa with a capacity of 134 500 bbl/d is operated by Maple Gas. Petroperu operates the remaining four refineries: Talara, Iquitos, Conchán and El Milagro with capacities of 992 000 bbl/d; 217 000 bbl/d; 260 000 bbl/d and 5 000 bbl/d respectively. Additionally, it carries on the largest network of retail oil products distribution (Ministerio de Energía y Minas, 2003)

2.2.4. Economical benefits

The participation of the energy and mining sector in the national GDP of 2007 was 6%, from which 0.96% corresponded to the oil industry. It is through the hydrocarbons canon that the country receives part of the income generated from the extraction of its lands. In

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2007, the transferred hydrocarbons canon was 1220 million soles, mainly coming from Cuzco region (38.2%) and Loreto region (24.2%) Between 1993 and 2003, Peruvian crude oil exports represented 5.8% of the country’s total exports, while imports of crude oil and derived fuels accounted for 10% of imports in the same period. (Ministerio de Energía y Minas, 2003). Later on, the initiation of exploitation activities of the Camisea natural gas fields increased the contribution of the energy sector to the country’s GDP. Currently, the national natural gas reserves are 4.7 times larger than the crude oil ones.(WEC, 2007). In summary, oil industry accounts for a minor part of the national budget and the country’s total exports (8.6 %). However, forecasts predict a sustainable positive future for Peruvian hydrocarbons. Due to numerous discoveries of gas and petroleum reserves in the recent years, government expects investments of US$20.000 million in the next 10 years. Thus, Peru is projected to become an exporter country of petroleum in 2010 after being a pure importer for many decades. Definitely, foreign and national investment in this sector will remain strong and the Peruvian government is keen to maintain and increase these major projects. However, each stage in oil life cycle carries hazard for humans, wildlife and the environmental systems. So far, these oil operations have overlapped with some of the most biodiversed areas of rainforest and the ancestral territory of many indigenous people.

2.3. Environmental and health impacts of oil explotation

2.3.1. Oil production phases

The impacts of oil exploitation on the environment and public health can be described according to different stages. The exploration is the search for deposits beneath the earth's surface. Suspected areas are initially subjected to gravity surveys to detect large scale features of the sub-surface geology. Features of interest are then subjected to more detailed seismic surveys and when a prospect passes the selection criteria, an exploration well is drilled to conclusively determine the presence or absence of oil. Afterwards, oil extraction can be achieved by primary recovery methods, when the underground pressure in the oil reservoir is sufficient to force the oil towards the surface. When the pressure falls, the remaining oil is extracted using secondary methods like water injection into the reservoir. Tertiary methods are also used to reduce the remaining oil viscosity, these include: oil burning, use of detergents and carbon dioxide flooding. The last stage is refining, where crude oil is processed and refined into more useful petroleum products, such as gasoline or diesel fuel. (The Center for Health and the Global Environment Harvard Medical School, 2002) Oil refineries are typically large sprawling industrial complexes with extensive piping running throughout, carrying streams of fluids between large chemical processing units.

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2.3.2. Environmental impacts

They commence with the exploration phase, where the construction of new roads and the mobilization of heavy equipment into relatively pristine environmental areas, not only disrupt and deforest the habitat, but also cause human encroachment. Specifically, canalization of land surfaces for pipeline routing often allow saltwater intrusion into brackish ecosystems. In developing countries, pipelines are often laid above ground instead of burying them because it is less expensive but more harmful for livestock, farmland, wild fauna and humans. (Orta, 2007) Continuing with the drilling and extraction phase, there is the problem of the produced water discharge to the water river. Produced waters come from the combination of the formation water (a natural water layer in the oil reservoir) and the water that is usually injected into the reservoirs to help force the oil to the surface. Both formation and injected water are eventually produced along with the hydrocarbons. (Stanislav, 2004) For instance, the oil fields of Jibarito and Jíbaro in the Corrientes river basin currently produce 8,500 barrels of oil per day with 151,000 barrels of produced water per day (proportion 1/18) (Pluspetrol Norte 2006) Produced water generally contains oil-based fluids and mud containing alkalis, bactericides, and mercury. But also, heavy metals, volatile aromatic hydrocarbons, among other contaminants to the sea or river water. (Orta, 2007) Produced water could be treated using a range of mitigation techniques, however, due to their cost and lack of environmental standards is rarely employed. (The Center for Health and the Global Environment Harvard Medical School, 2002) During the transport, large-scale oil spills mainly affect native fauna. Oil spills can cause widespread mortality in fish populations, with cascading impacts for other species and human populations that depend highly upon fish for subsistence. Sometimes, oil spills can affect plant life in profound ways. In temperate regions, salt marshes are most vulnerable. In tropical regions mangrove swamps are susceptible to damage from oil spills as their roots are above ground. (The Center for Health and the Global Environment Harvard Medical School March, 2002) Finally, during the refining, part of the crude oil is not processed and released into the environment. Additionally, the big refinery units vent dangerous hydrocarbons, fuel gases and particulate solids into the atmosphere. These, together with evaporated wastes released into the water, are accumulated in the atmosphere and return in the form of acid rain. The combination of the effects of oil spill and acid rain resulting from gas flaring produce soil degradation which affects crop yield and harvest. (Orta, 2007)

2.3.3. Human health effects

Many effects have been reported either from occupational or non occupational exposure. The first has been related with an increased risk for testicular cancer and leukaemia as well as dermatological conditions such as contact dermatitis, acne, neoplastic change of the skin, among others. On the other hand, no occupational exposure has also been related with an incremented risk of cancer, although the International Agency for Research on

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Cancer (IARC) has not yet reported a real evidence of carcinogenicity of crude oil in humans. (San Sebastián et al., 2001) Focused on the Amazonian countries, San Sebastian et al. reported elevated rates of spontaneous abortion and a higher risk of other adverse health effects such as skin mycosis, tiredness, itchy nose, sore throat, headache, red eyes, ear pain, diarrhea and gastritis. Studies evaluating cancer found an increase in hematopoietic cancers in children as well as a higher overall incidence of cancer in both men and women in countries with more than 20-year oil exploitation. (San Sebastián et al., 2001) According to Guidotti, exploration and drilling are the most hazardous sectors of the oil industry (Guidotti, 1995) for the great list of contaminants produced to which humans are exposed to. For instance, some oxides of nitrogen, sulphur and carbon produced during the drilling phase may cause bronco constriction and lung edema; as well as problems in the coagulation system. Similarly, mercury’s exposure through contamination of fish is believed to cause birth defects, heart problems and severe neurological disorders. Additionally, during the drilling and production process, workers are exposed to a high risk of accidents and high levels of disturbing noises.(Orta, 2007) During the roads construction in tropical territories, the accumulation of water is unavoidable; it leads to mosquitoes proliferation and increment of malaria cases. Some statistics of the malaria cases in the Brazilian Amazon showed that more than 50% were due to the Trans- amazónica road construction in 1974. In the Ecuadorian Amazon, epidemics of malaria, flue, hepatitis, sexually transmitted diseases and deterioration of the indigenous traditional lifestyle were associated with migratory work for oil industry. Finally, oil spills contaminate cultivable lands and water rivers - placing subsistence farmers at risk for food insecurity – and eliminating the safe drinking water supply for a community. (The Center for Health and the Global Environment Harvard Medical School March 2002) Looking at the impacts on quality of life, oil spills have adverse impacts on cultural values. For instance, the Ogoni community in Nigeria has suffered the death and possible extinction of their medicinal plants and herbs. In general, ,most of these herbs and plants are found in sacred grooves, shrines and forests, which have fallen under direct destruction in the course of oil exploitation and the toxicity of oil pollution. Additionally, the industry invasion of many indigenous territories originates the disintegration of customs, traditions and social values. (United Nations, 2007)

2.4. Peruvian amazon and oil industry

2.4.1. Amazon basin

The Amazon basin is considered the planet’s greatest reserve of biodiversity, its territory of 800 million hectares is shared by Brazil, Bolivia, Colombia, Ecuador, Venezuela, the Guyanas and Peru. Because they help to mitigate the greenhouse effect, they are considered vitally important in maintaining the world’s environmental equilibrium.

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The Peruvian Amazon is the area of the Amazon jungle that is confined within the territory of Peru and it stretches in a crescent shape from Ecuador, across Colombia and Brazil to the Bolivian border. It comprises 61% of the country’s territory and is one of the areas with greatest biodiversity and endemism in the planet, attributed to its high variety of ecorregions. (IIAP, 1987) Contradictorily, its large territory is the least populated in the country with just 11% of the total population. Within the Amazon basin it is possible to identify two natural regions: the highland jungle and the lowland jungle. In terms of political division, there are 5 regions which comprise the Peruvian Amazon: Amazonas, Loreto, San Martín, Madre de Dios and Ucayali. The principal Amazonian city is Iquitos at Loreto Region, other important cities are: Pucallpa, at Ucayali region; Puerto Maldonado at Madre de Dios region; Yurimaguas at Loreto region; among others . (IIAP, 1987)

2.4.2. Loreto region

Loreto is Peru's northernmost region, located in the Amazon basin. (Figure 1) With a territorial extension of 368,852 km2, it is the nation's largest region and the home for 891 700 inhabitants (3.3% of the country population) including a large number of indigenous rainforest people like the Achuar, Quechua, Urarina, and Secoya. (INEI 2007) Loreto is made up of high and low jungle and all of its territory is covered by thick vegetation and watered by the Marañón, Ucayali, Napo, and Amazon rivers. Politically, it is divided into 7 provinces: Maynas, Alto Amazonas, Datem del Marañón, Loreto, Mariscal Ramón Castilla, Requena and Ucayali, each one of which is divided into 4 - 13 districts. (Figure 2) Iquitos (Province of Maynas) is the only large urban center in Loreto, and it is accessible only by air or river.

Figure 2. Location of Loreto region and its seven provinces

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Loreto's economy relies on basic agriculture, fishing, lumber from the Amazon Rainforest to the outside world, and it offers modern amenities for the residents and tourists in the area. Other industries include rum, beer production and oil. (INEI, 2007)

2.4.3. Petroleum industry

The oil bonanza in the Peruvian Amazon began in 1970 when many foreign companies were given an open invitation to test and drill for the first time in the Loreto Region. In the following years, an intense cycle of land concessions for exploration and extraction resulted in the loss of control over oil industry from the national company Peru Petro. Nowadays, almost the entire Amazon has been divided into lots/blocks to be offered for oil and gas exploration and production. International oil companies control about 48.5 million hectares of rainforest lands, constituting an astounding 70 % of the total 68 million hectares of Peruvian rainforest. (Earth Rights International, 2007). These companies are obligated to pay the petroleum canon and over canon to the local governments (districts, provinces and regions). Both are particular forms of taxes regulated by each region’s legislation. . For Loreto region, canon accounts for 10% of the total oil production and it is distributed like this: 52% to the regional government, 40% to the municipalities, 5% to the Amazon National University and 3% to the Peruvian Amazon Research Institute. (Sociedad Nacional de Minería, Petroleo y Energía, 2007) As mentioned before, production of Block 1-AB and 8X represent more than the half (65 %) of Peru's total crude oil production. Both are located in Loreto Region, specifically in the basin of the Corrientes River.

2.5. Corrientes river basin

2.5.1. Location

The Corrientes is a tributary of Tiger river. Having its headwaters in the Ecuadorian highlands, it flows south-east, crossing the Peruvian border where it drains in the Tiger river. The Tiger together with the Pastaza confluence in the Marañon, which is one of the main tributaries of the Amazon river. Corrientes is a navigable river for its 425 km in the Peruvian territory, at Loreto Region. It flows through the Trompeteros district, and its basin, with an area of 15 thousand square kilometers hold 35 villages of indigenous communities.

As other tropical forest rivers, it is considered one of the Global 2000 Ecoregions for the conservation of biodiversity in the planet. Furthermore, it is the traditional territory of the Achuar people and few Urarinas and Quechuas communities.

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2.5.2. Population

2.5.2.1. Demographic information

As mentioned before, there are 35 indigenous communities along the Corrientes river basin, which belong to the Trompeteros district. Estimated total population for Trompeteros was 6621 in 2005 (MINSA, 2006) , from which 79 % is ethnically indigenous and the rest are mestizos who manly live in Villa Trompeteros, the district’s capital, or work in the oil company’s operation areas. Within the indigenous population, Achuar group is the most representative, accompanied by few Urarinas and Quichuas communities. Achuar population has one of the highest crude birth rate (38/1000) in the country (20.5/1000) (MINSA, 2006) which is mainly attributed to the cultural traditions enhancing reproductive activities at early ages and the lack of a good family planning system. (Caritas del Peru, 2007) It is a very young population where 52% is younger than 15 and the average age is 19 years. Sex is equally distributed with 50.8% men and 49.2 women. (MINSA, 2006) In average, each indigenous community concentrates a population of families and 154 people. (Pluspetrol, 2006) Their households are located in clusters nearby the common areas such as the school, health post or the communal meeting center.

2.5.2.2. Socioeconomic information

Despite the profitability from the petroleum industry in their lands, total population is considered poor. More than 85% has at least one unsatisfied basic need, being dwelling quality the most frequent, followed by overcrowding and access to education. (MINEM, 2008) Deficiencies of other basic services are reflected in the inaccessibility to clean water (25%), sewage (55%) and electricity (57%) (Pluspetrol, 2006). One evaluation in six communities reported that 85.75% of the families consumed grounded water, 85.1% threw their feces to the land and 61.3% threw the wastes to the precipice. Dwellings were mainly built by rustic materials and the limited number of rooms made them live in overcrowding. (Cáritas del Perú, 2006) Another evaluation in 7 communities (DIGESA, 2006) revealed that only 48% of the families had mosquito nets, which leave them exposed to the endemic malaria. Looking at the human development index, Trompeteros (0.49) figures in the last quintile of all Peruvian districts (INEI, 2005) The indicators described in Table 1 put Trompeteros below the national average (0.59) and even below the regional average (0.53) (INEI, 2005) The principal economic activities such as hunting, fishing and agriculture are geographical- cultural and subsistence based. In some areas, extractive wood activities constitute another source of sustainability. (MINSA, 2006) However, they have experienced lower production and availability of their agricultural and animal livelihoods along the years (ERI, 2007), which is attributed to the environmental pollution from the oil extractive activities.

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Table 1. Human Development Index indicators for Peru, Loreto and Trompeteros district Peru Loreto Trompeteros Life expectancy at birth (years) 78.7 66.5 66.4 Adult literacy rate (% ages 15 and older)

87.9

79

75.6

Combined primary, secondary and tertiary gross enrolment ratio (%)

85.8

84.4

72.5

GDP per capita

$ 6039 $57.3 $50.4

Development index 0.773 0.53 0.49

The main mode of transport is the river, using motor or rustic boats. The time to travel between one to another community varies from 8 to 72 hours, the air access is restricted for the petroleum company.

The population counts with the radiophone system, available in some communities and extremely important to maintain contact with the two health centers in all the district (MINSA, 2006)

2.5.2.3. Education

The 40.4% speaks only their native language, 37.2% are bilingual and 22.4% (mainly the group aged less than 18 years) speaks only spanish. There is a notorious disadvantage in the women educational level caused in part by their cultural traditional believes, still practiced nowadays. (MINSA, 2006; Cáritas del Perú, 2006)

2.5.2.4. Cultural aspects

The Achuar have their own language, which belongs to the Jíbaro linguistic family. Along the years, they have maintained not only their traditional environmentally sustainable lifestyle based on hunting, fishing, shifting cultivation, and raising fowl, but also their beliefs system and cosmology. Their organization is based on the Apus; the community leaders who must be contacted before any activity is carried out in the community’s territory. In 1991, they formed the federation FECONACO with the aim to represent their collective needs and defend their rights, particularly from the oil exploitation activities. (MINSA, 2006)

2.5.2.5 Health

2.5.2.5.1. Health status Ill health for the Achuar was initially perceived as an abnormal disequilibrium that could be attributed to witchcraft, natural evolution or inappropriate behaviors and were regularly controlled using curative plants. However, the conception changed with the processes of migration, industrialization and availability of health care services. Nowadays, the general population reports an exponential multiplication of signs, symptoms and chronic conditions, overwhelming thee capacity of the health care services. (MINSA, 2006)

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Summarizing the 2005 records from Villa Trompeteros, Pampa Hermosa and Providencia Health centers, the most prevalent diseases are respiratory infections, febrile syndrome, acute diarrhea, malaria nutritional deficiencies and skin and subcutaneous tissue pathologies. However clinical records only reflect the diagnosis of all reported cases but not the ill health condition of the whole population. Important to highlight is the popular attribution of the higher prevalence of skin and subcutaneous conditions, compared to other nearby river communities (13% in the Corrientes, 8.6% in the Pastaza) to the contact with the river or streams’ waters. Nutritional deficiencies are also ascribed to the scarce availability of food sources because of the environmental contamination. (MINSA, 2006) 2.5.2.5.2. Health care provision and accessibility Some key aspects have been pointed out by the Public Health Committee of the Peruvian Medical College, (Colegio Médico del Perú, 2007) to describe the inefficiency of the health care provision system in the Corrientes: Only 4 health centers exist to cover the population of 35 communities, being the Villa Trompeteros health center, the first reference place in the district. Unfortunately, it lacks of a surgery unit, x – ray equipments, diagnostic laboratories among others. Given the long distance and transport limitations for the people, health brigades provide mobile service, visiting the communities every 2-4 months. Nevertheless, the scarce availability of health workers impedes the fulfillment of the great demand for medical attention. (MINSA, 2006). The whole district has an average 4 times lower than the Loreto’s region, including 0.13 medical doctors , 0.13 nurses, 0.13 midwifes and 0,13 dentists per 1 thousand people. Most communities (29) have health promoters who have received training to diagnose and give medication for the most prevalent diseases like malaria. An evaluation of their performance and impact over the health improvement in the communities would be necessary to reinforce basic concepts of primary health care. On the other hand, incomplete health insurance and insufficient provision of medicines limits the services demand when acute symptomatology is not present. Furthermore, cultural barriers like the language or gender stigmas reduce the demand for medical attention. (MINSA, 2006) A specific public health problem is the previously reports of heavy metals poisoning. Despite population concern, sanitary officers haven’t yet identified the sources, being unable to monitor the contamination and give solutions.

2.5.3. Oil exploitation in the Corrientes river

The territory on the Corrientes River was first explored for petroleum in 1969 by the national company PetroPeru. In 1970, petroleum lands in the provinces of Loreto and Alto Amazonas in Loreto Region, were divided into two lots. Lot 1AB, in the upper basin of the Pastaza, Corrientes and Tigre rivers and Lot 8, grouping the blocks 8 and 8X, located in the middle and lower basins of the Corrientes river (Earth Rights International, 2007) In 1971, the Peruvian government and the American company Occidental Petroleum Corporation of Peru (OXY) signed a contract for Block 1AB. One year later, OXY drilled

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the first productive well and later on, Blocks 1AB and 8 became the most productive in the country, contributing with 65% of national petroleum production (calculation based on data from DGH 1999). In 1996 and 2001, blocks 8/8x and 1AB respectively were transferred to Pluspetrol Corporation S.A. (later Pluspetrol Norte S.A). In 2001, the Peruvian government extended the original period of exploitation for Block 1AB until 2015, and Block 8 to 2026 (Apoyos and asociados, 2006).

Of the crude oil extracted from these two blocks, 45.9% is sold on the international market to clients such as Shell, Enap, Chevron-Texaco, Glencore and Trafigura, contributing to the national treasury and domestic energy consumption (Apoyo and asociados, 2006). In Peru, as in many other countries, oil is the ¨center of current industrial development and economic activities, but at the same time is the heart of some of the most troubling environmental, health, and social problems…¨. (Rourke & Connolly, 2003)

In the Corrientes river basin, there is sufficient evidence that oil industry has brought up high contamination levels with serious effects on the land, air, flora, fauna, and probably to the indigenous people health who live in the area. (La Torre, 1999)

2.5.4. Environmental impacts

For the last 30 years, oil exploitation has contaminated the Corrientes river basin, affecting the aquatic environment, the soils and the fish fauna. According to the Peruvian Water Law, Corrientes River waters are classified as `Waters of areas for the aquatic fauna preservation and recreational or commercial fishing’, not recommendable for human consumption, although it has always been a basic element for the Achuar communities traditional lifestyle. A report from IIAP (1987) found high concentrations of lead and copper in the Corrientes river waters as well as in the tissues of consumable fish. In 1998, a territorial environmental evaluation of the Tigre-Pastaza basin (including the Corrientes River) reported a historical environmental damage caused by petroleum exploitation in the region. High concentrations of oils, fats and mercury were found in all the rivers receiving production waters. The samples of surface water as well as of the sediments, presented high concentrations of hydrocarbons, heavy metals and chlorides and 427 ha in the Block 8 and 10 538 ha in the Block 1AB were classified as ¨seriously to moderately affected by deforestation¨. The perforation of 348 wells was estimated to have contaminated 52.2 ha. (Ministerio de Energía y Minas 1998) In 2004, the Regulatory Body for Energy Investment (OSINERG) found 36 of 46 soil and river water samples from oil activities exposed areas had contamination levels above the maximum permissible limits'. In 2005, the Direction of Environmental Health (DESA) performed new water analysis recording an increased water salinity level and chloride concentration in the Corrientes and other Amazon tributary rivers. Concerning lead, samples of stream water and “residual waters” exceeded acceptable limits (0.03 mg/ L) according to the General Water Law (DESA) and WHO recommendations (0.01 mg /L). Yet, it is not clear whether the

22

produced waters themselves are the lead source, but it is likely that the oil activities have caused the lead contamination, possibly from leaching from polluted sites or from spills. (ERI, 2006) Cadmium and copper concentrations were difficult to evaluate, given the lack of these parameters in the water law and the high detection limits used for the analysis (0.01mg Cd/L compared with the recommended limit 0.004 mg Cd/L). Other analyses on the carcinogenic PAHs, reported levels far above the recommended concentrations in superficial waters from the Corrientes River. In sediments, analysis detected elevated concentrations of chromo (7–32 mg/kg P.S), manganese (37 – 860 mg/kg PS), mercury (0.1–0.15 mg/kg PS), lead, (5-28 mg/kg PS), zinc (12.5–247.3), barium (20–192 mg/kg PS) and boron (4 –78 mg/kg P.S). (DESA, 2005)

2.5.5. Health impacts

In 2005, DIGESA applied a baseline lead and cadmium evaluation in seven Achuar communities, including a sample of 125 adults and 74 children (1-17 years old). Acceptable WHO blood lead levels (10 µg/dL) were exceeded in 66.21% in the children group and in 79 % of the adults group; 98.7% of the children exceeded acceptable blood cadmium limits for people not occupationally exposed (< 0.1 µg Cd/dl), 37.8% were classified as at risk with 0.21–0.5 µg Cd dl–1 and 59.46% exceeded the biological tolerance limits (BTL) ( > 0.5 µg Cd/dl). Almost 100% of the adults presented cadmium blood levels over the established permissible limits and 68%, over the BTL. The publication of these results caused great concern in the communities and intense lobbying lead DIRESA Loreto to plan a new evaluation in all the Corrientes population. In 2006, they visited two communities San Cristobal and Jose Olaya with the aim of collecting data on nutrition, three heavy metals: lead, cadmium and mercury; and provide medical attention. The published results showed again high levels of lead and cadmium

Lead contamination has several adverse effects such as on the haematopoietic system, alterations to the immune system and kidney damage. The IARC has classified lead as a ‘possible human carcinogen’; and the most likely are lung, stomach cancer and gliomas (Järup, 2003). In children, the adverse effects include cognitive deficits, neurotoxicity, behavior disorders, slowed growth, reduced heme synthesis, and impaired hearing (Bradman, 2001). The United States Centers for Disease Control (CDC) indicates 10 ug/dl as the limit to initiate public health actions. Nevertheless, it recognizes that no safe BLL is known and that even BLLs less than 10 ug/dl for long-term in children may lead to diminished intellectual capacity. Concerning cadmium toxicity, several European studies have shown kidney damage in general population at urinary cadmium levels around 2–3 µg Cd/g creatinin. But also, effects on bones causing fractures at lower exposure levels. (Järup, 2003)

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III. JUSTIFICATION OF THE STUDY

It is now more than three decades since oil industry settled down in the Achuar home lands bringing up serious consequences for the ecosystem and population health. To date, Corrientes communities (represented by their federation FECONACO) have a long history of denunciations and objections against the company’s operations. (FECONACO, 2007). These lobbying actions, together with the implementation of new legislation and State supervision activities, have led to the performance of various analysis to measure the environmental impacts and two surveillances to address possible health impacts. The last surveillance was carried out by DIRESA Loreto in July 2006. Two communities, San Cristobal and Jose Olaya, were visited to provide general medical attention and collect data on nutrition and heavy metals levels. As a result, the final report showed high levels of lead and cadmium. However, no evaluation on the compiled data was performed and valuable information on the relationship between heavy metals levels and nutritional status remained unknown. The hypothesis for this relationship lies on the impact that nutritional status may have over the absorption of an environmental toxicant. For instance, lead concentration has been inversely correlated with iron deficiency and short stature. (Bradman et al., 2001; Kordas et al., 2009), but positively associated with weight for height. (Elias et al., 2007). However , there are contradictory findings from cross sectional and longitudinal studies that keep this association unclear and reveal the need for more accurate methods to outline plausible explanations (Kordas et al, 2009) Thus, having available data and given the suggestive evidence, we considered worthwhile to evaluate whether nutritional status and heavy metal levels could be associated in these two communities.

IV. OBJECTIVES

3.1 OVERALL OBJECTIVE

To determine the relationship between the levels of heavy metals and health in the population of the communities San Cristóbal and Jose Olaya.

3.2 SPECIFIC OBJECTIVES

- To determine the level of nutrition by anthropometric measures and presence of anemia. - To reanalyze the data of heavy metals in biologic samples - To evaluate the association between heavy metals in the biologic samples and the nutritional indicators of this population.

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V. METHODS

5.1. STUDY DESIGN This is an observational, cross sectional study 5.2. SETTING AND PARTICIPANTS The setting is located in the Trompeteros district, in the Loreto region. Trompeteros district comprises a superficial area of 12,246 km2 and holds a population density of 1.84 inhabitants/ km2. The surveillance was performed in two communities, San Cristobal and Jose Olaya. A brief characterization in given in Table 2, and their localization appears in Figure 2. Thus, the study population corresponded to both communities’ inhabitants, willing to participate. Overall, 152 people were enrolled in the study.

Table 2. Socioeconomic characteristics of the two study communities.

Jose Olaya San Cristobal

Population 152 , 78 men and 74 women 32, 17 men and 15 women

Main activity agriculture agriculture

Education One primary school with one bilingual teacher

-

Health service

No health centre One health promoter gives first aid care and transfer the patients to Huairi medical unit (Pluspetrol company)

No health centre Patients seek medical assistance in Villa Trompeteros health centre or in the Pluspetrol medical unit.

Basic services No potable water system Electricity service available 10% families count with artisanal letrinas

No potable water system No electricity service available The entire population consume water from the Corrientes river

Source: Pluspetrol, 2006

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Figure 2. Map of the Corrientes river basin with the 35 indigenous communities

LEYEND Distric’s Capital Achuar community C. San Cristóbal River Quichua community Oil pipeline Urarina community C. Jose Olaya

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5.2. DATA COLLECTION As previously mentioned, this study is focused in the reanalysis of a data set, collected by the DIRESA of Loreto Region, between July and October 2006. The survey in two communities was planned in May 2006, by DIRESA, and FECONACO, conceived as the start point of the “Comprehensive health care plan for the indigenous communities of the Corrientes river basin, currently affected by the oil environmental impact”. The fieldwork was performed by DIRESA LORETO and CENSOPAS and was supported by FECONACO and PLUSPETROL NORTE S.A. All the activities were developed in two time periods, from18th till 21st July in San Cristobal and from 24th till 26th July, in Jose Olaya. The main activities included: - Meetings and discussions with the communities’ authorities. - Collection of census registries. -Clinic examinations developed by family doctors, pediatricians, neurologists and psychologists. Pharmacological treatment was provided when necessary. - Registration of anthropometric measures: height and weight in all the population - Collection of biologic samples in population older than one year: blood samples were analyzed to obtain hematocrit values and blood lead levels. Twenty four hours urine samples were analyzed to obtain cadmium and mercury levels in urine per gr/creatinin. 5.3. HEAVY METALS MEASUREMENT Samples of 6ml of venous blood from fasting subjects were obtained and collected in sodium heparin vacutainer tubes. Additionally, participants were required to give their 24-hour urine samples in plastic containers with one-fold dilution of nitric acid 5% v/v. The analysis was performed at CENSOPAS laboratory in Lima. Blood lead and urine cadmium levels were measured by atomic absorption spectrophotometry using quelation technique. Mercury levels in urine were measured using a visible spectrophotometric method. The creatinin concentration was obtained by the kinetic method with the Kinetic Creatinin AA Kit, Wiener Laboratory. (CENSOPAS, 2007) The reference values for BLL were 10 ug/dl for children, as the limit suggested for the CDC to initiate public health actions; and 20 ug/dl for adults, as the absorption limit for people not occupationally exposed to lead, according to the American Conference of Governmental Industrial Hygienists (ACGIH), Deutsche Forschungsgemeinschaft and Lauwerys and Hoet. (DIGESA 2006)

For cadmium and mercury in urine, the values of 0.8 μg/g creatinin and 1 μg/g creatinin were used as recommended by the Human Biomonitoring Commission for Germans non smokers. (Wilhelm et al., 2004). The cutoff points used to establish categories for each metal were adapted from the CENSOPAS Laboratory report, based on Lauwerys and Hoet analysis. (CENSOPAS, 2007)

5.4. NUTRITIONAL STATUS INDICATORS Anemia prevalence was determined according to WHO anemia criterion cut off values, based on the 5th percentile from the third National Health and Nutrition Examination

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Survey (NHANES III), shown in Table 3. Children nutritional status was assessed using the anthropometric measures: Height-for-age (HAZ), weight for age (WAZ) and height-for-weight Z-scores (WHZ), according to standardized methods. (Dzieniszewski J, Jarosz M, Szczygie et al., 2005) Thresholds of Z-score less than -2 were used to indicate stunting (HAZ), undernutrition (WAZ) and wasting (WHZ). Adult’s nutritional status was determined by the body mass index (BMI)

Table 3. Age- and sex-specific cutoff values for anemia

Based on the 5th percentile from the third National Health and Nutrition Examination Survey (NHANES III), which excluded persons who had a high likelihood of iron deficiency

5.5. ETHICS The study was approved by the DIRESA Loreto Ethics Committee and the representatives of FECONACO with the restriction to collect biological samples from children under 1 year old. Prior data collection, free informed consents were signed by all heads of the families. 5.6. DATA ANALYSIS

The information was recorded in an Excel file and analyzed using STATA version 10 software. Anthropometric measures Height-for-age (HAZ) , Weight for height (WHZ) and Weight for age (WAZ) were computed using the program NutStat from Epiinfo (CDC). Description of categorical variables was summarized by tables of frequency and percentage. Whereas, arithmetic means were calculated to report continuous variables: hematocrit levels, HAZ, WHZ, WAZ, BMI and heavy metal levels. Association of anemia prevalence with age group, sex and community was performed by cross-tabulations and χ2 test. Correlation of nutritional variables with age and sex was assessed by the Pearson correlation coefficient while correlation between heavy metal levels and the same demographic variables was assessed using the Spearman test. To compare means of continuous variables, t-test for independent samples was performed.

Hto % Children (age in years) 1- <5 33 5- 12 34.5 Men (age in years) 12-<15 37.3 >=15 39.0 Non pregnant women (age in years) 12-<15 35.7 >=15 35.9 Pregnant women 33.0

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Associations between heavy metal levels and nutrition variables were examined by simple regression analysis, which were developed by three age groups, given that the dose response effect varies according to this variable. Because histograms reflected skewed distributions of lead, cadmium and mercury levels, their correspondent logarithms were calculated and applied in the linear regression analyses.

VI. RESULTS

6.1. SUBJECT SAMPLE SIZE Among the total population (184) from the two communities, 152 (39 from San Cristobal and 114 from Jose Olaya) were recruited (response rate, 82.6%) and the rest were not present the day of the surveillance. Missing values of some variables, especially heavy metals levels and hematocrit concentrations, were due several reasons: children under one year were not authorized to provide either blood or urine samples; some individuals were not present the day of the samples collection; and some samples were insufficient for the laboratory analysis. 6.2. DEMOGRAPHIC CHARACTERISTICS Of a total 152 participants, 114 (75%) came from Jose Olaya. Overall, the gender distribution was nearly even with a lightly larger women population of 52.6% in San Cristobal and 59.7% in Jose Olaya. A majority of the study population was adult (18 years old and above), with 65% in San Cristobal and 42% in Jose Olaya (Table 4) .

Table 4. Distribution of the population by communities, age and sex

Community Age (years)

Sex Total M F n % n % n %

San Cristobal

0-6

4

17.6

6

28,6

10

23.7%

7-17 1 5.9 3 14,3 4 10.5% 18 and > 13 76.5 12 57,1 25 65.8%

Total 18 47.4 21 52.6 39 100,0%

José Olaya

0-6

21

43.8

16

24.2

37

32.5%

7 – 17 8 39.6 21 43.9 29 25.4% 18 and > 19 16.7 29 31.8 48 42.1%

Total 48 42.1 66 57.9 114 100.0%

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6.3. NUTRITIONAL DATA Of the 56 children, only one had evidence of wasting. Though, of 66 children, 16.6 % had evidence of underweight and 27.5% showed signs of stunting (Tables 5-7). Of the 64 adults, 69% had a normal BMI. (Table 8) Neither the three anthropometric variables nor BMI was correlated with sex. However, HAZ and BMI were positively correlated with age (r:0.3; r:0.8 respectively) The means of the three anthropometric measures in children and the BMI in adults corresponded to the normal ranges for each age group. (Table 9). HAZ mean was significantly lower in the younger group (p=0.05)

Table 5. Weight for height z score

Table 6. Height for age z score

Table 7. Weight for age z score

Age (years)

Sex Under Normal Over Total n % n % n % n %

1-6

M 0 0 20 100 0 0 20 100 F 1 5.3 18 94.7 0 0 19 100

7-17 M 0 0 5 100 0 0 5 100 F 0 0 11 90.9 1 9.1 12 100

Total 1 1.8 54 96.4 1 1.8 56 100

Age (years)

Sex Under Normal Over Total n % n % n % n %

1-6

M 7 35 12 60 1 5 20 100

F 4 21 13 68 2 11 19 100

7-17 M 2 33 4 67 0 0 6 100

F 5 24 16 76 0 0 21 100

Total 18 27.5 45 68 3 4.5 66 100

Age (years)

Sex Under Normal Over Total n % n % n % n %

1-6

M 6 31.6 13 68.4 0 0 19 100 F 2 10.5 17 89.5 0 0 19 100

7-17 M 1 16.7 5 83.3 0 0 6 100 F 2 9.1 20 90.9 0 0 22 100

Total 11 16.6 55 83.7 0 0 66 100

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Table 8. Distribution of the Body mass index Adult population

Table 9. Summary of anthropometrics and BMI

6.4. HEMATOCRIT LEVELS Hematocrit levels showed a prevalence of anemia in 73.4 % of the total population. (Table 10). The calculated means by age groups are shown in Table 11. Anemia prevalence was significantly higher in Jose Olaya compared to San Cristobal. (chi2:6.7, p=0.01).

Table 10. Anemia status

Sex

<18.5 Underweight

18.5-24.9 Normal

25 -29.9 Overweight

>30 Obese

Total

n % n % n % n % n % Male 0 0 18 69 7 27 1 4 26 100

Female 1 3 26 68 8 21 3 7 38 100 Total 1 1.6 44 68.7 15 23.4 4 6.3 64 100

1-6 years(n:39) 7-17years(n:27) 18->years (n:64) Mean,(SD), range Mean,(SD), range Mean,(SD), range

HAZ -0.9 (2.3), -5.1- 8.5 -1.6(0.8), -3.9- -1.9 -

WAZ -1.0(1.15), -2.9-2.37 -1.3(1.04), -5.6-0.7 -

WHZ -0.3(0.8), -2.0- 1.8 -0.3(1.0), -1.9- 2.5 -

BMI - - 24.1(3.1), 17.8-32.5

Age group

Anemia Normal Total

n % n % n %

1-6 years M 12 75.0 4 25.0 16 100

F 13 92.8 1 7.14 14 100

7-17 years

M 5 83.3 1 16.7 6 100

F 14 66.7 7 33.3 21 100

18-> years M 17 77.27 5 22.7 22 100

F 19 63.3 11 36.7 30 100 Total 80 73.4 29 26.6 109 100

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Table 11. Summary of Hto levels (%) by age groups n mean SD range 1- 6 30 31.3 2.4 25-36 7-17 27 32.9 3.3 28- 40 18> 52 35.5 3.4 27- 43

6.5. HEAVY METALS LEVELS Lead. Table 12 and Graph 1 summarize BLL means and distribution according to the classical categories; 61% of children between 1-6 years old and 82% of the children between 7 – 17 years old had BLL ≥ 10 μg/dL. Whereas, 21% of the adults had BLL levels ≥ 20 μg/dL Average BLL were significantly higher in Jose Olaya than in San Cristobal (H: mean(JO) - mean(SC) >0, p= 0.001) . As expected, BLL increased significantly with the age (Spearman p= 0.2 p:0.02).

Table 12. Blood lead levels (ug/dl)

Graph 1. Age group proportions of BLL (ug/dl) categories

Mean,(SD), range 0-9.9 10-19.9 20- 29.9 30-50 Total

n % n % n % n % n %

Community

San Cristobal 9.9;(5.7) 3.3- 31.7 18 54.5 13 39.4 1 3.0 1 3.0 33 100

Jose Olaya 13.6;(5.7) 3.3- 27.5 15 18.1 53 63.9 15 18.1 0 0 83 100

Age group 1-6 10.2;(4.4) 3- 20 11 39.3 15 53.6 2 7.1 0 0 28 100 7-17 11.9;(4.8) 3- 23.3 5 18.5 20 74.1 2 7.4 0 0 27 100 18 and > 13.9; (6.6) 3- 31.7 17 27.9 31 50.8 12 19.7 1 1.6 61 100 Total

12.6; (5.9) 3- 31.7

116

100

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Cadmium. Overall, 50% (51) of the study population presented urine cadmium levels up to the reference value 0.8 ug/gr Creatinin (Table 13 and Graph 2). By groups, 56% of the children between 1 to 6 years , 31% of the children between 7 to 17 years and 55% of the adults, exceeded the reference value. No significant difference was found in the arithmetic means between communities. (H: mean(JO) - mean(SC) >0, p= 0.2) Neither sex nor age seemed to be correlated with cadmium levels. (Spearman= 0.1 p>0.05)

Mercury Most of the study population (89%) had levels below the recommended limit (1ug/gr Creatinin). However, both means, of San Cristobal community and children aged 1 -6 years, significantly exceeded 1 ug/gr Creatinin. (Table 14 and Graph 3). As with Cadmium, means didn’t differ between communities. (H: mean (JO) – mean (SC) >0, p= 1)Neither age nor sex was correlated with urine mercury in this sample. (Spearman=-0.07, p>0.05)

Table 13. Urine cadmium levels (ug/gr Creatinin)

Graph 2. Age group proportions of Urine Cd levels (ug/gr Creatinin) categories

Mean,(SD),range 0- 0.8 0.9-1.9 2-3.9 4-7 Total

n % n % n % n % n %

Community

San Cristobal

1.2, (1.1) 0.2- 6.1 22 62.8 7 20.0 5 14.3 1 3 35 100

Jose Olaya 1.4, (1.2) 0.03- 7.5 29 43.3 22 32.8 14 20.9 2 3 67 100

Age group 1-6 1.4,(1.3) 0 - 6.1 10 43.5 8 34.8 4 17.4 1 4.4 23 100 7-17 0.9, (0.8) 0.1-3.0 15 68.2 4 18.2 3 13.6 0 0 22 100 18 and > 1.5, (1.3) 0.1- 7.5 26 45.6 17 29.8 12 21.1 2 3.5 57 100 Total 1.4, (1.2) 0.0-7.5 102 100

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Table 14. Urine mercury levels (µg/g Creatinin)

Graph 3. Age group proportions of Urine Hg levels (ug/gr Creatinin) categories

6.6. RELATIONSHIP BETWEEN HEAVY METALS AND NUTRITION VARIABLES Graphs 4, 5, 6 and 7 show the scatter plots between BLL in logarithm scale and nutrition variables, together with the correspondent regression coefficients. For cadmium and mercury, only associations with hematocrit levels are shown (Graphs 8 and 9). Results on the relationship between Cd/Hg with anthropometric measures are not shown because of lack of scientific evidence showing possible associations between them.

Mean, (SD) range 0- 1 1.1- 4.9 5-> Total

n % n % n % n %

Community

San Cristobal 1.9,(1.6) 0.3- 2.7 18 64.3 8 28.6 2 7.1 28 100 Jose Olaya 0.9,(0.6) 0.03-7.5 63 94.0 4 5.9 0 0 67 100 Age group 1-6 1.6, (1.6) 0.04- 7.5 16 72.7 5 22.7 1 4.6 22 100 7-17 1.0, (1.1) 0.03- 5.4 23 92 1 4.0 1 4.0 25 100 18 and > 1.1, (0.8) 0.03- 3.2 42 87.5 6 12.5 0 0 48 100 Total

1.2, (1.1) 0.02- 7.5

95

100

34

No significant association was found either between blood lead levels and anthropometric measures or between BLL and hematocrit concentrations in this study population.

Coef St. Err p- value 1-6 0.19 2.5 0.9

7-17 -3.4 3.4 0.3 18-> 1.2 2.0 0.5

Coef St. Err p- value 1-6 0.6 1.9 0.7

7-17 0.6 0.7 0.3

Graph 4.Relationship between Hto and BLL (log scale) by age

Graph 5. Relationship between Height for age and BLL (log scale) by age group

-50

510

.5 1 1.5

1-6 years 7- 17 yearsHAZ

log BLL

2530

3540

4525

3035

4045

.5 1 1.5

.5 1 1.5

1-6 years 7-17 years

18 - > years

log BLL

35

-2-1

01

-2-1

01

25 30 35 40 45

25 30 35 40 45

1- 6 years 7- 17 years

18- > years

hto

Cd (log scale)

Coef St. Err p- value 1-6 -0.75 1.32 0.5

7-17 -0.28 0.6 0.1

Coef St. Err p- value F 0.5 3.03 0.8 M 4.4 3.7 0.2

Coef St. Err p- value 1-6 0.04 0.03 0.2 7-17 0.01 0.03 0.5 18-> -0.1 0.01 0.4

1520

2530

35

.5 1 1.5 .5 1 1.5

F MBMI

log BLL

Graph 6. Relationship between Weight for age and BLL (log scale) by age groups

Graph 7. Relatinship between BMI (adults) and BLL (log scale) by sex

-6-4

-20

2

.5 1 1.5

1 - 6 years 7 - 17 yearsWAZ

log BLL

Graph 8. Relationship between Hto and Urinary Cd(ug/gr Creatinin (log scale) by age group

36

-2-1

01

-2-1

01

25 30 35 40 45

25 30 35 40 45

1- 6 years 7- 17 years

18-> years

Hg (log scale)

hto

VII. DISCUSSION

Our results not only confirm the already published data on high levels of lead and cadmium, but also give an overview of the nutrition situation. Most relevant, a possible association between nutrition and heavy metal levels has been explored. Findings from this study are meant to contribute in framing and understanding the nature of the impacts that environmental, socioeconomical and other contextual factors have had over this population health. (Dipak & Gautam, 2006)

Nutritional status in Latin-American countries as Peru is characterized by a ¨high/very high prevalence of stunting combined with a low prevalence of wasting, indicating a predominance of chronic undernutrition in children under 5 years.¨ (WHO, 2007) This statement coincides with our findings, where children under 7 didn’t show evidence of wasting, but 28% were classified as stunted and 21% as undernourished. Using stunting as our proxy for chronic malnutrition, our population shows a worst situation than the national context (25% of chronic malnutrition for children under 5). (INEI, 2000) Nutritional status in adults was measured by their BMI and anemia prevalence. BMI is an indicator mainly used for recording obesity statistics, but it is also a well accepted indicator of nutritional status in adult populations, especially in community surveys. (Chakraborty & Bose, 2008). Of our total adult population, almost no one had underweight, but particularly, 23% were classified as overweight and 6% as obese. Anemia prevalence in this group reached to 85%. In these communities, the coexistence of anemia and overweight-obesity can reflect the already reported nutritional deficiencies in diet, caused by the lack of protein and vitamin sources, which are replaced with higher carbohydrates and fats intake. (MINSA, 2006)

Coef St. Err p- value

1-6 0.1 0.04 0.09 7-17 0.06 0.03 0.06 18-> -0.01 0.76 0.5

Graph 9. Relationship between Hto and Urinary Hg (ug/gr Creatinin (log scale) by age group

37

The whole panorama on nutrition displays the combination of a high prevalence of anemia, malnutrition affecting at least 30% of the children and adolescents and signs of overweight and obesity in the adult group. Based on the literature (Abudayya et al, 2007) and regional evidence (MINSA, 2006) our findings could be explained by a lack of essential micronutrients in diet, combined with a high prevalence of parasite infections in an area with poor sanitary conditions and great pollution from the oil industry. To the last respect, studies show that both Ecuadorian children and adults exposed to oil contamination, displayed significantly higher levels of malnutrition and anemia than those non exposed. (Unión de Promotores Populares de Salud de la Amazonía Ecuatoriana, 1993) Concerning the three heavy metals assessment, lead poisoning seems to be the most frequent in this study population. Lead is a worldwide environmental contaminant related with several health effects (Nragu, 2008). CDC established BLL of 10 ug/dl as the limit to take public health actions, but not as a threshold for the harmful effects of lead. (CDC, 2007) In our study population, 61% of the 1-6 years group had levels above 10 ug/dl, which is higher than the 43% (14) reported by DIGESA, who performed an evaluation in other 7 indigenous communities. (MINSA, 2006). In contrast, the proportion of children and adolescents (1-17 years) with more than 20 ug/dl (7%) is half the one reported by DIGESA (14%). Only 32% of adult population had BLL higher than 10 ug/ dl, significantly lower than the 79% showed by DIGESA. Nevertheless, 21% of our study population showed BLL above 20 ug/dl while DIGESA didn’t report any participant with this BLL. Thus, lead poisoning seems to affect a larger population of young children in this study compared to the DIGESA population but with lower BLL. In contrast, a completely reverse situation is observed in the adult group.

The previously reported direct association between age and BLL (Kaiser, 2001) is applicable to our findings where the mean of the 1-6 years old group (10.2 ug/dl) was significantly lower than the 7-17 years group’s (11.9 ug/dl) Explanations would be based in both, the different sources of exposure and the gradient of the dose response effect at different ages. (MINSA, 2006)

Looking at the Peruvian context, the BLL mean in the study children (10.2 ug/dl SD=4.4) is higher than the reported in El Callao (9.6 mg/dl SD=6.2) and in Lima (7.1mg/dl SD= 5.1) (Espinoza et al, 2003) but significantly lower than the reported in La Oroya (43.5 μg/dl) (DIGESA, 1999). To our understanding, these three settings have well identified sources of lead such as the vicinity with mineral storage areas, exposure to leaded gasoline and contamination from a mining and smelter center, respectively. However, no clear lead source can be regarded in our studied communities. Though, some environmental analysis attribute the causality to the hydrocarbon activities (Orta et al. 2007) , more specific studies are needed to clarify the real exposure sources. Measurements of urinary cadmium reported half of the population had levels above the reference value 0.8 ug/gr creatinin, with a children mean 1.4 ug/g creatinin (SD=1.3) which results higher than the 95th percentile of the U.S. population = 1.03 μg/g creatinin and the average levels found in Czech Republic, Great Britain and Sweden (below 0.6 ug/gr creatinin) (cited from Zubero, 2008). Unfortunately, DIGESA, in its study of 2005, measured cadmium in blood, so the different parameters impede further comparisons with

38

our findings. Common risk factors for cadmium poisoning are smoking and diet (ATSDR, 2002). In our study population smoking would be discarded, given the extremely low smoking prevalence (Cáritas, 2006). However, high consumption of contaminated fish could be an important source of exposure.

Regarding mercury, levels in this population were lower than the reported in other Amazonian territories where mining is a clear exposure. (Zubero, 2008) Though, the mean in children aged 1 -6 years, (1.6 mg/gr creatinin, SD= 1.6) significantly exceeded 1 ug/gr creatinin , this was lower than the reported in Andean areas such as La Oroya, where mining industry was attributed to cause urinary cadmium levels more than six times the U.S. average of 1 mg/gr. creatinin. (Serrano et al., 2007)

An interesting finding is the different average levels of lead, cadmium and mercury, in both communities, which may be related with the location and the proximity to potential exposure sources. Although neither cadmium, nor lead release to the environment are known to be related with oil activities, more research is necessary to clarify the real sources of exposure. Finally, we evaluate the possible association between heavy metals levels and nutrition, having in mind that our results couldn’t be conclusive due to the complex interaction of different nutritional variables that was not approached in this study. According to Goyer’s review, toxic metals like cadmium, lead and mercury may interact metabolically with nutritionally essential metals. For instance, iron deficiency could increase the absorption of cadmium, lead, and aluminum. (Goyer, 1997) In our study population, hematocrit concentration as an indicator of iron deficiency was not associated with BLL, which might be explained by the fact that anemia screening (with hematocrit or hemoglobin) is not efficacious to diagnose iron deficiency as other recommended tests like Serum ferritin, transferrin saturation, and free erythrocyte protoporphyrin (FEP) (Kazal, 1996). In fact, many studies have supported the indirect association between lead poisoning and iron deficiency (Bradman et al, 2001; Elias et al., 2007; Frisancho et al., 1991; Kordas et al., 2009; Selevan et al., 2003, Wright et al., 2003) but taking Serum ferritine test to determine iron deficiency.

On the other hand, many authors support the argument that iron nutritional deficits that retard growth or reduce weight may increase lead absorption. (Kordas et al, 2009) Therefore an indirect association between lead and anthropometric measures would be expected. Our results don’t show such associations, but it is not totally surprising, given the inconsistency of previous studies that have investigated BLL with height, weight and body-mass index. (Frisancho et al., 1991; Ballew et al., 1999; Selevan et al., 2003).

Uncertainty still remains about this relationship, given that no biological mechanism has been developed yet and the cross sectional design of most of the studies, makes impossible to advert the history of lead exposure or nutritional deficiencies in a specific population.

39

Regarding urinary cadmium level, it didn’t show any association with hematocrit level although it has been proved that iron deficiency increases cadmium absorption from the gastrointestinal tract. (Goyer, 1997) As in the case of lead, it might happen that evaluating iron deficiency through hematocrit levels may not be as appropriate as blood ferritin levels (Kazal, 1996). Neither urinary mercury level was associated with hematocrit level. But in this case, evidence doesn’t show any direct connection with iron deficiency.

This study has some limitations beginning with its cross-sectional design, which doesn’t allow evaluating the dose response effect of lead exposure over nutritional status or vice versa. As mentioned before, hematocrit is not the best indicator for diagnosing iron deficiency and therefore not ideal to evaluate an association with lead or cadmium poisoning. However, limited resources often restrict the availability of other tests. At last, some difficulties during the samples collection and analysis in the laboratory may be determinant for our results. For instance, it is difficult to ensure that the 24 hours urine sample to measure cadmium and mercury contained the real volume excreted in 24 hours, both because of the environmental conditions and the inexperience of the own participants to do such procedure.

VIII. CONCLUSSIONS

The nutritional status was characterized by a high prevalence of anemia in the total population, signs of chronic malnutrition affecting at least 30% of the children and adolescents and presence of obesity/overweight in a third part of the adult group. The means BLL were consistent with previously reported levels by DIGESA in 2005 in other 6 Achuar communities. No association was found either between BLL, urinary cadmium and urinary mercury level with nutritional status, defined by hematocrit levels (anemia), anthropometric measures and BMI in this study population. However, some limitations like the use of a proxy indicator of iron deficiency and the cross sectional design might have impeded us to see the real situation. In other settings, health officers create their own references values, according to each population´s internal exposure. (Batariova et al., 2006) A similar strategy could be applied in the Corrientes communities. Establishing a baseline with a representative sample would allow the construction of adequate references values which then could serve for monitoring programs activities. Moreover, given the moderate blood levels and relatively high cadmium levels, attempts to tackle the problem should focus in identifying the sources and develop preventive strategies

40

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