Zulin Zhang

Short- and Long-term Temporal Trend of Organic Contaminants in Soils

Following Single or Multiple Applications of Sewage Sludge to Pastures

Global Chemicals Overview • Chemicals are an integral part of

modern daily life. • Global production: 1 MT to 400 MT

between 1930 and 2000. • Global chemical output value:

US$4.12 trillion in 2010. • Over 143,000 chemicals registered in

EU of 2011 (> 1000 t or highly hazardous).

• The growing rate is over 25% between 2012 and 2020 (Table 1).

• Over 50% of total production with environmentally harmful compound .

Emerging Organic Contaminants: POPs and EDCs

Persistent Organic Pollutants (POPs): •Persist in the environment. •Long-range transport. •Bio-accumulate through the food web. •Pose a risk of causing adverse effects to human health and the environment.

Endocrine disrupting chemicals (EDCs): •Substances may interfere with normal function of the endocrine (hormone) system of humans and animals.

Effects on Animal and Human ?

Eggshell thinning in birds of prey

Reduction in frog population

Adverse effects on fish reproduction and development

Development of male sex organs in female marine animals such as whelks and snails

Declines in the numbers of males born

Reductions in male fertility

Female reproductive diseases

Earlier puberty

……

Disposal of Sewage Sludge

EU 27 member states: > 10 M tons (dry solids) annually, rise to 13 M tons of 2020.

Agricultural application as fertiliser

Incineration

land filling

Compost

Others… 41%

19%

17%

12%

11%

EU - 27

Agricultural Use Incineration Landfill Compost Others

Agricultural use of Sewage Sludge in EU and Worldwide

EU 27: >40% sludge applied to land.

EU 7: >50%, UK, France, Ireland, Spain, Slovakia, Portugal and Denmark.

EU 6: <1%; Not authorised to use: Romania, Belgium (Brussels and Flemish region). <1%: Greece, Netherlands, Slovenia.

USA: >7.1 M tons (dry solids), >60% applied to land.

China: 30 M tons, 10-15% applied to land.

Land Application of Sewage Sludge: Benefit and Concern

Benefit

Low cost for the disposal of sewage sludge. Recycling plant nutrients: P, N, S, K, Cu, Zn… Improved soil organic matter, structural properties and soil

moisture retention. Return carbon to soil and reduce in the atmosphere.

Concern

Pathogens Heavy metal Organic contaminants Accumulation in soils and transfer to plants and grazing

livestock and soil invertebrates Evaporate and transport to air, surface and groundwater

Organic Contaminants in Sewage Sludge and Soils

Bisphenol A

Polycyclic aromatic hydrocarbons (PAH)

Polybrominated diphenyl ethers

(PBDE)

Alkyl phenols (detergents)

Plastics – (phthalates)

Dioxins Polychlorinated biphenyls (PCB)

Pesticides

Pharmaceuticals

Bisphenol A (BPA)

BPA: 2,2-Bis-(4-hydroxphenyl)propane

(CH3)2C(C6H4OH)2.

BPA: used as plastics and epoxy resins. e.g. baby and water bottles, food and beverage cans, sports equipment, lining water pipes; thermal paper…

Global consumption of BPA: > 5.5 M tons in 2011.

BPA found in 96% of US pregnant women of 2011 study.

BPA in sewage sludge: low µg/kg – mid mg/kg (dw).

The Debate over BPA Safety

Previous study: Low estrogenic activity compared with estradiol.

Recent works: As effective as estradiol in triggering some specific receptor responses.

European Commission's Scientific Committee on Food, the EU's European Chemicals Bureau, and the US FDA: current levels of BPA present no risk.

American Medical Association, Experts in the field of endocrine disruptors etc: the entire population may suffer adverse health effects from current BPA levels.

US FDA (2012), EU (2011) and Canada (2008) banned the use of BPA in baby bottles while still use in other products.

Glensaugh Research Station

Hartwood Research Station

3 plots: treated 3 plots: control 1 yr treatment

2 plots: treated 1 plot : control >13 yrs treatment

Treated: 2.25 tonnes sewage Sludge per hectare

Control: 225 kg of Inorganic Fertiliser (N) per hectare

Both sites treated with the sludge from the same WWTP

Experimental - (Study 1: Glensaugh; Study 2: Hartwood)

Experimental – Analytical Methods

Zhang et al (2011)

GC-MS

Selective Pressurized Liquid Extraction (SPLE)

Concentration of BPA in Sewage Sludge

Sample Source BPA (ng/g,dw) Reference

Granada, Spain 5-680 Dorival-Garcia et al., 2012

Gran Canaria, Spain 1.4-54.9 Vega-Morales et al., 2011

Greece 620 Gatidou et al., 2007

Germany 4-1363 Fromme et al., 2002

South California, USA 66-217 Yu and Wu, 2012

USA 4600 Kinney et al., 2008

Ontaria, Canada 4-74 Chu et al., 2005

Scotland, UK 636 This Study

Zhang et al (2015)

BPA changes in Sewage Sludge Amended Soils – Study 1 (Glensaugh, Single Application)

Zhang et al (2015)

BPA changes in Sewage Sludge Amended Soils – Study 2 (Hartwood, Multiple Applications)

Zhang et al (2015)

Other studies on organic contaminants changes in sludge-amended soils

PCB burdens of sludge amended plots closely followed that of the control in short-term experiment (Alcock et al., 1995)

The sludge-amended soils (over 20 years of treatment) contained over 5 times more total PCBs than the control plot (Alcock et al., 1995)

Chlorobenzenes in both control and sludge-amended soils were very low and almost indistinguishable in the short term study (Wang et al. 1995)

All the Chlorobenzenes in the sludge-amended soil (over 20 years of treatment) increased and remained higher than those in the control even after sludge application ceased (Want et al., 1995).

Similar to that found for PPBDEs in other study (Eljarrat et al., 2008)

Mean soil concentrations of other OCs in sewage sludge treated soils (Single Application, Glensaugh)

Rhind et al (2013)

Mean soil concentrations of other OCs in sewage sludge treated soils (Repeated Application, Hatwood)

Rhind et al (2013)

Partitioning equilibrium of BPA within the three-phase by Fugacity Model

Zhang et al (2015)

Results of the plant uptake and human exposure by Fugacity Model

Zhang et al (2015)

Estimation of Estrogenicity

EEF = EC50E2 / EC50compound ---------- (1)

EEQ = EEF × Ccompound ---------- (2)

- EEF: Estradiol Equivalent Factor

- EEQ: Estradiol Equivalent Concentration (EEQ)

(Stahlhut et al., 2009)

The number of unshelled mud-snail obviously increase at 1 ng/g EEQ level (Duft et al., 2003).

Estrogenicity of BPA EEF=0.0066 E2 ?

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

25/08

/2010

17/09

/2010

30/09

/2010

22/10

/2010

05/11

/2010

18/11

/2010

07/03

/2011

17/03

/2011

04/04

/2011

19/04

/2011

04/05

/2011

18/05

/2011

Date

EE

Q (n

g/g)

CT

0

0.2

0.4

0.6

0.8

1

1.2

2009-4-2

2009-5-27

2009-8-5

2009-8-31

2009-9-22

2009-10-21

2009-11-19

2009-12-21

2010-2-10

2010-3-17

2010-5-26

2010-7-15

2010-8-10

D ate

EE

Q (n

g/g) C

T1T2

Single Application Multiple Application

Only 1 multiple treatment sample over 1 ng/g.

Balaguer et al. 1999; Pillon et al.2005

Estrogenicity of BPA EEF ≈ E2?

0.001.002.003.004.005.006.007.008.009.00

10.0011.0012.00

25/08

/2010

17/09

/2010

30/09

/2010

22/10

/2010

05/11

/2010

18/11

/2010

07/03

/2011

17/03

/2011

04/04

/2011

19/04

/2011

04/05

/2011

18/05

/2011

Date

EE

Q (n

g/g)

CT

Single Application Multiple Application

Control: 72% > 1ng/g Treated: 100%: > 1ng/g

Control: 76% > 1ng/g Treated: 100%: > 1ng/g

Stahlhut et al., 2009

0

20

40

60

80

100

120

140

160

180

2009-4-2

2009-5-2

7

2009-8-5

2009-8-3

1

2009-9-2

2

2009-10-2

1

2009-11-1

9

2009-12-2

1

2010-2-1

0

2010-3-1

7

2010-5-2

6

2010-7-1

5

2010-8-1

0

D ateC

on

cen

trat

ion

(ng

/g)

C

T1T2

On-going Work

Effect of Bulky Organic Fertilisers on Amended Soils

On-going Experiment Glensaugh: Laundry field Long-term (aims: >10 years) Initiate: Sept 2013 4 different treatments: Sewage Sludge (SS) Green compost Farmyard manure Inorganic fertilizer Treated rate: 2/a, Spring&Autumn Replicates: 4 Plots: 16 (each plot: 3 m×3 m) Sampling rate: Week 0, 2, 4, Month 2, 4, 6 and then every 6 months. Monitoring Contents: Pollutants in water, soils, herbage and earthworms (EDCs and metals) Invertebrate population (nematode) Herbage height Soil Organic Matter

Long-term BOFs Amended Soils Experiment

Acknowledgment

Carol KYLE Rupert HOUGH

Morgane LE VELLY Elizabeth DUFF

Stewart RHIND Helen RUFFIE

Craig MCKENZIE Emma CALMETTES

Mark OSPREY Dave HAMILTON

Scottish Government’s Rural and Environment Science and

Analytical Services (RESAS) Division

Thank You!