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ENVIRONMENTAL FATE AND BIOACCUMULATION

Processes in the environment : fate of chemicals

Sorption to sediment particles

Anaerobic degradation

Resuspension sedimentation

Uptake (accumulation)

IKAN

Sorption to suspended particles and dissolved organic carbonAerobic degradation

Xfree Xbound

Air

Water

Sediment

BURUNG

Transport between media : example sediment-water

Assumption of equilibrium :

Equilibrium partition :

Medium 1e. g. water Cw

Medium 2 e. g. sediment Cs

Kp : partition coefisient sediment-water/ sorption coefficient

Kp = Cs/Cw

sediment

water

air

Partitioning between sediment (or soil) and water

Assumption of Equilibrium partition :

Medium 1e. g. water Cw

Medium 2 e. g. sediment Cs

Kp : partition coefficient sediment-waterKp = Cw/Cs

Koc : organic carbon normalized partition coefficientKoc = Kp/foc

Cs = concentration in soil or sedimentCw = concentration in waterfoc = fraction organic carbon in sediment or soil

Partitioning between sediment (or soil) and water

Sediment particle Kp : partition coefficient sediment-waterKp = Cs/Cw

Koc : organic carbon normalized partition coefficientKoc = Kp/foc

Koc is a property independent of the type of sediment or soil

Organic carbonfoc = 0,01

foc = 0,05

Kp

foc

Koc

Soil sorption coefficient of a new chemicals

Chemical log Kow log Koc

Benzene 2,19 1,96Toluene 2,79 2.39Naphthalene 3,30 3,11Anthracene 4,45 4,27PCB245245 7,16 5,65ppDDT 6,91 5,31ppDDE 6,96 4,82

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Hydrophobicity as important parameter : the octanol-water partition coefficient : Kow

Hydrophobicity is tendency of a chemical to “escape” water, and it depend on :

Hydrophobic phases : lipid phase (biota) organic carbon (sediment)

- Size- Presence of polar groups H2O

Chemical x

KowMethanol 0,17Acetanol 0,58Benzene 134DDT 1,0 107

Soil sorption in relation to hydrophobicity

log Koc versus log Kow

0

2

4

6

8

0 2 4 6 8

log Kow

log

Koc

Bioaccumulation

Topics :

models for accumulation

different sources of uptake

influence of properties on accumulation, including biotransformation

Uptake and elimination processes

BiotransformationUptake Fish

Cf

Reproduction kr

Elimination

ke

km

Growth γ

From van Leeuwen and Henmens, 1995 : Risk Assessment of Chemicals Chapter 3 (van den Berg et al.)

Three uptake routes : water, food and sediment

Water (Cw)

Food (Cfood)

Sediment (Cs)

kw

kf

ks

Organism (Co)ke Surrounding

medium

From van Leeuwen and Henmens, 1995 : Risk Assessment of Chemicals Chapter 3 (van den Berg et al.)

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Partitioning between sediment (or soil) and water : bioavailability

Assumption of Equilibrium partition :

Medium 1e. g. water Cw

Medium 2 e. g. sediment Cs

Kp : partition coefficient sediment-waterKp = Cs/Cw

Koc : organic carbon normalized partition coefficientKoc = Kp/foc

Cs = concentration in soil or sedimentCw = concentration in waterfoc = fraction organic carbon in sediment or soil

Uptake for water, food or soil

Bioconcentration BCF Co/Cw uptake from waterfactor

Bioaccumulation BAF Co/Cw uptake from water andfactor food, or sediment

Biomagnification BMF Co/Cf uptake from foodfactor

Biota to sediment BSAF Co/Cs uptake from water andaccumulation factor food, or sediment

Co = consentration in organismCf = consentration in foodCs = consentration in sediment

Influence of properties on accumulation

Accumulation depends on :• Hydrophobicity• Size• Ionization• Stability of the parent compound (biotransformation)

BiotransformationUptake Fish

Cf

Reproduction kr

Elimination

ke

km

Growth γ

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Ecotoxicity evaluation

Bird MammalAmphibian

orReptile

IndirectToxicity

SoilInvertebrateCommunity

PlantCommunity

BenthicCommunity

FishCommunity

DirectToxicity

Contaminated Environmental Medium

Food chain

Ecotoxicity evaluationMammalian Pathway

Bird MammalAmphibian

orReptile

IndirectToxicity

SoilInvertebrateCommunity

PlantCommunity

BenthicCommunity

FishCommunity

DirectToxicity

Contaminated Environmental Medium

Food chain

Ecotoxicity evaluationFish eating Birds

Bird MammalAmphibian

orReptile

IndirectToxicity

SoilInvertebrateCommunity

PlantCommunity

BenthicCommunity

FishCommunity

DirectToxicity

Contaminated Environmental Medium

Food chain

Environmental Fate of Nitrobenzene:Physico-chemical properties Environmental Release:

Depending on its purity: pale yellow-brown oily liquid at room temperature; odor: bitter almonds and shoe polish (vapor pressure 0.27 mmHg @ 25°C)Released into environment from: primarily industrial uses (production of aniline, rubber chemicals, pesticides, dyes, pharmaceuticals); formed in the atmosphere by nitration of benzene

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In air levels: from industrial areas 0.09 ppb up to 3.5 – 5.7 ppb. Atmospheric samples were higher during summer, and lower during heavy rain or snow. Air sample over landfill max. 14.48 ppbIn surface water: only 0.4% of 836 stations and 1.8% of 1245 reporting industrial wastewatersIn soil: 8 ppm along Buffalo River in New York, but not in sediment samplesIn 1992 USA: total released 917 thousand pounds- to atmosphere: 52 thousand pounds (5.6%)- to surface water:442 thousand pounds To underground injection sites: 865 thousand pounds (94.32%)No nitrobenzene was released to land

Transport

Nitrobenzene will volatile slowly from soil to surface water and is subjected to biodegradationAdsorption and bioconcentration are not thought to be significant fate processes in waterNitrobenzene may leach through soil and is considered to have intermediate mobility

Transformation/Persistence - AIR

undergoes photolysis photoproducts: ortho- and para- nitophenols and nitrosobenzenelab test: 35% nitrobenzene photochemically degraded in 5 hours by irradiation of xenon lampchemical reacts slowly with hydroxil radicals and ozonehalf-life for reaction of nitrobenzene and hydroxyl radicals and ozone in moderately polluted air: 90 days and 2 yearsremoval by wet deposition is not significant

Transformation/Persistence - SOIL

Subjected to biodegradation in soilHowever results from screening test was conflicting: with activate sludge inoculum from 98% in 5 days to no degradation in 10 days

Transformation/Persistence - WATER

Subjected to biodegradation and photodegradationSmall amount also adsorb to sediment or volatile from the surfaceHalf-life in model waste stabilization ponds: 3.8 days; 89.5% of the added chemical was degraded; 4.9% volatilized, 2.3% adsorbed to sediment; 2.4% lost in effluent; and 1% remainedHalf-life in aquatic environments estimated: 0.3 days

Transformation/Persistence - BIOTA

Bioconcentration factors in two species of fish L.idus and P. promelas estimated at 15 and less than 10, and in P. reticulata: 3 Nitrobenzene is not expected to accumulate significantly in aquatic organisms, however, it has been shown to be taken and may bioconcentrate in terrestrial plants

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SOAL EKOKINETIKA

(Dikumpulkan minggu depan di TU TL, ditulis tangan pada HVS A4)

Pada area pertanian terdapat danau yang selama 20 tahun menerima limbah kimia. Analisis terhadap sedimen menunjukkan kandungan lindan 0,38 mg/kg. Terdapat hewan common tern dan otter yang makan ikan dari danau tersebut. Ada juga sapi, diambil dagingnya, yang minum dari danau.

Pertanyaan:

a. Berapa prediksi konsentrasi lindan di air danau?b. Berapa prediksi konsentrasi lindan di ikan?c. Berapa nilai BCF lindan terhadap ikan?d. Apakah dengan konsentrasi yang ditemukan akan

menyebabkan keracunan lindan pada Common tern dan otter?

e. Bila Max. Permissible Concentration (MPC) lindan di air pada Common tern 0,015 μg/L dan pada otter: 0,21 μg/L, berapa konsentrasi lindan yang boleh/harus ada di sedimen sehingga tidak membahayakan Common tern & otter.

f. Apa yang Saudara rekomendasikan dalam pengelolaan lingkungan untuk permasalahan ini? Uraikan!

Data: log Kow = 3,78, kw fish= 175 L/kg/d; log Kd= 2,4, BCFwet weight untuk lindan= 302 L/kg