FATEMOD MODELING FOR RISK EXPOSURE FROM CHEMICALS Jaakko Paasivirta, Department of Chemistry, University, Niilo Paasivirta, Suomen Postmaster (enterprise), Jyväskylä, Finland Risk management scheme (EPA) Risk management Risk estimation Control decision Dose/response assessment Risk characterization Hazard identification Acceptable level determination Control options Exposure assessment Feedback RISK CHARACTERIZATION (Germany) Risk = Extend of Damage * Probability of its Occurrence R= E x P Model Damokles: E high, P low (chemial accident) RISK CHARACTERIZATION (Germany) Risk = Extend of Damage * Probability of its Occurrence R= E x P Model Damokles: E high, P low (chemial accident) Model Cyclops: E high, P low (mass invasions of non-native species) RISK CHARACTERIZATION (Germany) Risk = Extend of Damage * Probability of its Occurrence R= E x P Model Damokles: E high, P low (chemial accident) Model Cyclops: E high, P low (mass invasions of non-native species) Model Pythia: E uncertain, P uncertain (gene modification) Model Pythia: both E and P uncertain RISK CHARACTERIZATION (Germany) Risk = Extend of Damage * Probability of its Occurrence R= E x P Model Damokles: E high, P low (chemial accident) Model Cyclops: E high, P low (mass invasions of non-native species) Model Pythia: E uncertain, P uncertain (gene modification) Model Pandora: E uncertain, P high (PET compounds – damage is irreversible) RISK CHARACTERIZATION (Germany) Risk = Extend of Damage * Probability of its Occurrence R= E x P Model Damokles: E high, P low (chemial accident) Model Cyclops: E high, P low (mass invasions of non-native species) Model Pythia: E uncertain, P uncertain (gene modification) Model Pandora: E uncertain, P high (PET compounds – damage is irreversible) Model Cassandra: E high, P high (Climatic change - people do not believe) Cassandra was a profet knowing the future. But people did not believe her (cource of Ares). Here Aigistos and Klytaimnestra are murdering Agamemnon and Kassandra RISK CHARACTERIZATION (Germany) Risk = Extend of Damage * Probability of its Occurrence R= E x P Model Damokles: E high, P low (chemial accident) Model Cyclops: E high, P low (mass invasions of non-native species) Model Pythia: E uncertain, P uncertain (gene modification) Model Pandora: E uncertain, P high (PET compounds – damage is irreversible) Model Cassandra: E high, P high (Climatic change - people do not believe) Model Medusa: E low, P low (high frequency electromagnetic fields. Many believe that risk is high). Images of Medusa Gorgon USA a.d. 2001 Syracuse 580 b. Chr. RISK CHARACTERIZATION (Germany) Risk = Extend of Damage * Probability of its Occurrence R= E x P Model Damokles: E high, P low (chemial accident) Model Cyclops: E high, P low (mass invasions of non-native species) Model Pythia: E uncertain, P uncertain (gene modification) Model Pandora: E uncertain, P high (PET compounds – damage is irreversible) Model Cassandra: E high, P high (Climatic change - people do not believe) Model Medusa: E low, P low (high frequency electromagnetic fields. Many believe that risk is high). Environmental risk assessment of chemical Properties of the chemical and the environment Exposure assessment (modelling) PEC Predicted Environmental Concentration Tests, QSAR, Analyses Effect potency assessment (ecotoxicology) Risk ratio: Ro = PEC / PNEC by emission Eo RISK EMISSION = Eo / Ro Modeling for prediction of the fate of chemical in environment PNEC Predicted No-Effect Conentration Machbetin kohtalon ennustaminen: eksaktia noituutta! To predict fate of Machbet: Exact witchcraft ! CemoS programs: Trapp & Matthies (1996) English Handbook: Springer 1998. AIR. Concentrations caused from continuous point-source emission. PLUME. Concentration in Air after point emission event. LEVEL 1. Identical with the Mackay Level 1 model. LEVEL 2. Concentrations by continous emission, residence time in system and ("Level 4") recovery from contamination BUCKETS. Transport of compound in surrounding soil layer. SOIL. Vertical movement and fate of chemical in different soil contamination types. PLANT. Uptake by plants from soil and air. WATER. Concentrations in River or river-like water system. CHAIN. Chain reaction ----> bioaccumulation in a food chain. FATEMOD model -> Modified Mackay level 1-4 model for fate of chemical in a one box six compartment catchment area environment (WINDOWS program) -> Values of the physical properties and degradation lifetimes of the chemical are automatically adjusted for ambient temperature and pH values of water and soilwater -> Level 1 and 2 output can be used as compound property values in other specific fate models like CemoS and bioaccumulation models -> Level 3 output gives realistic estimates of levels and residence times by constant emission in non equilibrium steady state -> Level 4 output presents concentrations at different times after stop of emission (a steady state prediction to the future) -> To include transport of chemical within catchments, FATEMOD for the joint areas can be run successively. Then, the modelled flows from one area are considered as emissions to the adjacent neighbour area -> The properties of environments and compounds including correction coefficients for temperature adjustments are recorded in the editable database of FATEMOD. Report to EXEL takes place by push button EXAMPLE OF APPLICATIONS: Use of the FATEMOD model in the environmental risk estimation of chemicals in discharges Jaakko Paasivirta, Seija Sinkkonen, Markus Soimasuo, University of Jyväskylä, Finland FATEMOD database: parametrization of the values for properties of the environments and chemicals Properties of the environments. Instead using unit world box 1 x 1 x 1 Km as suggested by D.Mackay Multimedia Environmental Models L-242, Lewis, Chelsea, MI, USA) suitable for general risk estimation of chemicals, we adopted natural catchment areas as model environments to achieve more flexibility for different cases of risk evaluations. Properties of the chemical compounds. Molecular properties: Name, Group, Subgroup, CAS register number, Molar mass (WM), Melting point (Tm K), Entropy of Fusion (ΔSf), Liquid state molar volume (Vb), pKa (for acids or bases) Temperature-dependent properties: Log(pr) = Apr – Bpr. Vapor pressure in liquid state (Pl Pa), Solubility in water (S mol m-3), Henry’s law function (H Pa m3 mol-1), Hydrophobity LogKow (where Kow is the octanol-water partition coefficient) and…. Degradation half-life times HL(i) (i = 1 air, 2 water, 3 soil/plants and 4 sediment; reference time HLT (usually 20 or 25 C) Air FATEMOD environment: catchment area Water ¤ Sizes etc: Area, Depth, Density, Soil / Plants pH, Fraction of organic carbon Sediment ¤ Processes:Advections (flows), Diffusions, Suspended Solids Evaporation, Depositions ¤ Temperature Fish Norw ay o 29 KemR 67 Arctic o Kemijoki River catchment area (51120 Km 2). Mean annual temperature +1 OC Circle km 0 N 100 200 Sw eden Russia Bay of Bothnia South-West Finland area (36358 Km 2). Catchment of the Rivers flowing to the Bothnian Sea. Mean annual temperature +8 OC Finland SWF S Jyväskylä Bothnian Sea Ladoga Helsinki Gulf of Finland Stockholm Baltic Sea Gotland Estonia St.Petersburg FATEMOD window for editing property values of the environment box Southwest Finland (SWF) = catchment area of the Finnish Rivers flowing to the Bothnian Sea. Major compartments for mass balance: Air, surface Water, Soil (including surface plants), and Sediment. Minor compartments for concentration data: Suspended sediment and Fish (aquatic biota). FATEMOD editing window for substance parameters Determination of the compound property as function of temperature (SUBCOOLED) LIQUID STATE VAPOR PRESSURE VPLEST for evaluation the coefficients Apl and Bpl for: Log Pl = Apl - Bpl / T Method is from Clark F. Grain in Handbook of Chemical Estimation Methods, W.J.Lyman, W.F.Reehl and D.H.Rosenblatt (Eds), ACS, Washington, DC (1990) in Chapter 14. Liquid state vapor pressures are computed in one Celsius intervals at environmental range (e.g. -2 to + 30C) by Grain’s equation 14-25 using one known Vp and temperature as reference. Then, the coefficients are determined by linear regression. The reference Vp can be for either solid or liquid state (Ps or Pl). They can be converted to each other by equation: Log Ps = Log Pl + ∆Sf x (1-Tm/T) / (R x Ln10) 0bs. R x Ln10 = 19.1444 OH Conversions between temterature coefficients for Vp’s are: Aps = Apl + ∆Sf / (RxLn10) and Bps = Bpl + ∆Sf x Tm / (R*Ln10) CH3 O2N VPLEST result for liquid state Vp’s of DNOC is: NO 2 Compound Mp C ∆Sf Pl(25) Apl Bpl Aps DNOC 86.5 57.04 0.243 11.31 3496 14.29 Bps 4567 124578-hexachloronaphthalene: Pl values by two methods 2 Pl (mPa) Cl 1.5 Cl Cl Cl Cl 1 0.5 Cl VPLEST GC Lei et al. 1999 0 0 5 10 15 t OC 20 25 30 OH Herbicide DNOC: evaluation of solubility coefficients for FATEMOD CAS 534-52-1, WM 198.122, Mp 86.5 C →Tm 359.65 K O2N Enthalpy of fusion Δ Hf = 20515 J mol-1 (DSC by C.Plato (1972) Anal. Chem. 44, 1531-1534). Entropy of fusion Δ Sf = ΔHf / Tm = 57.04 J K-1 mol-1. Liquid state molar volume Vb = 137.4 cm3 mol-1 [from increments NO 2 of P.Ruelle et al. (1991) Pharm. Res. 840-850. pKa = 4.31 Solubility parameter DB = Σ Fdi / Vb according to P.Ruelle (2000) Chemosphere 40, 457-512. Σ Fdi is the dispersion component of molar attraction constant calculated from increments of C.W.van Krevelen (1990) in: Properties of Polymers, Elsevier, Amsterdam, pp. 212-213. Value calcd. for DNOC = 18.20. Parameters needed for estimation of water solubility and hydrophobity of the chemicals are association terms [P.Ruelle (2000) Chemosphere 40, 457-512]. vAcc and vDon are the numbers of active sites. KAccW(i) and KDonW(i) are stability constants for proton acceptor and donor groups of the compound in the water. Similar terms for the compound in n-octanol are KAccO(i) and KDonO(i). The greatest value of these association terms, MAXW or MAXO are also needed in evaluation. Additionally, sum of the hydroxyl groups is NOH, and parameter boh has value of 1, 2 or 2.9 for primary, secondary of tertiary OH group, respectively. CH3 Example: association terms for DNOC are (KAccO values are zeros) vAcc 2 vDon 1 KAccW(i) 100,100 KDonW(i) 5000 MAXW 5000 KDonO(i) 5000 MAXO 5000 Solubility in water S mol m-3 WATSOLU.bas for evaluation the coefficients for: Log S = As - Bs / T WATSOLU is based on mobile order thermodynamics estimation for log S at 25 C (P.Ruelle et al. (1997) Int. J. Pharm. 157, 219-232). We have divided equations to temperature dependent (Bs/T) and non-dependent (As) parts: As = 5.154 + ∆Sf / (RxLn10) - 0.036xVb-0.217xLnVb + ΣNOHx(2+boh) / Ln10 + ΣvAcc(i)xLog(1+KaccW(i)/18.1) + ΣvDon(i)xLog(1+KDonW(i)/18.1) Bs = ∆Sf x Tm / (RxLn10) + (DB- 20.5)2 x Vb / (RxLn10) x Log (1+MAXW / 18.1) Example: Output from WATSOLU for DNOC: As = 4.617, Bs = 1071.7 VOLATILITY: Henry’s law fuction Simple conversions for Log H = Ah – Bh / T At the narrow temperature range of environments values of Ah and Bh are in fair agreement with the relation H = Pl / S. Therefore, FATEMOD model automatically calculates them by conversions Ah = Apl – As, and Bh = Bpl - Bs . Example: conversion result for DNOC: Ah = 6.693 Bh = 2424.3 600 OH CH3 O 2N 500 400 ry's n e H Law nt sta Con tion c Fun NO2 DNOC 300 200 H mPa m 3 mol -1 S (mg L-1) / 10 100 Pl mPa tC 0 0 5 10 15 20 25 30 Validation of S estimate by two independent methods: OH OCH3 Cl pKa = 4.31 Cl Cl WATSOLU of the HPLC pH eluent = 5.60 Tam D, Varhanikova D, Shiu WY and Mackay D (1994) J.Chem.Eng.Data 39, 82-86. Hydrophobity (lipophility) as Log Kow is also temperature-dependent! TDLKOW.bas for octanol/water partition: LogKow = Aow – Bow / T Is based on thermodynamic estimation of LogKow at 25 C of P.Ruelle (2000) Chemosphere 40, 457-512. We have divided Ruelle’s equations in two parts to obtain the temperature coefficients Aow and Bow: Aow = ∆B + ∆F + ∆Acc + ∆Don ∆B = (0.5 x Vb x (1/124.2-1/18.1) + 0.5 x Ln(18.1/124.2) / Ln10 ∆F = [(vB x (rw/18.1 – ro/124.2) – ΣNOH x (boh + rw – ro)] / Ln10 ΔAcc = ΣvAcc x Log[(1 + KaccO(i) / 124.2)/(1 + KaccW(i) / 18.1)] ΔDon = ΣvDon x Log[(1 + KdonO(i) / 124.2) / (1 + KdonW(i) / 18.1)] Bow = (Vb/(RxLn10)x[(DB-20.5)2/(1+MAXW/18.1)–(DB-16.38)2/(1+MAXO/124.2)] Where 18.1 is the molar volume of pure water, 124.2 the reduced molar volume of watersaturated n-octanol, rw structuration factor for water (2.0) and ro structuration factor for wate-saturated n-octanol. Observe that association coefficients for water are the same as those in WATSOLU.bas (see above). The temperature coefficient Bow is practically zero for compounds (often POP’s) having only one kind of substituents, but with several polar and different substituents in structure Bow can be significant. Example1: TDLKOW output for DNOC: Aow = 3.826 Bow = - 0.439 O2N Example 2: Musk xylene parameters from TDLKOW are Aow = 5.022 and Bow =361.6 in fair agreement of HPLC and literature values /J.Paasivirta, S.Sinkkonen, A-L.Rantalainen, D.Broman and Y.Zebühr (2002) Environ Sci & Pollut Res 9(5), 345-355/. NO2 NO2 Musk xylene HLT = 20 OC reference values for DNOC are HL(1) = 170 h, HL(2) = 500 h, HL(3) = 720 h, HL(4) = 1000 h QSPR estimation of the reference lifetimes. Example for polychloronaphthalenes (PCNs). Based on maximal and minimal HLT 25OC values in NCl classes of PCDF mode of Mackay et al. and QSPR from environmental data (J.Falandysz 1998). The most abundant PCN congeners in Baltic Sea are included here: Code Cl-subst. NCH-CH NβCls F ¤ HL(1) h HL(2) h HL(3) h HL(4) h CN42 1,3,5,7 0 2 13 522 1740 26100 87000 CN33 1,2,4,6 2 1 20 483 1610 24150 80500 CN28 1,2,3,5 2 2 26 444 1480 22200 74000 CN27 1,2,3,4 3 2 33 405 1350 20250 67500 CN35 1,2,4,8 2 3 33 405 1350 20250 67500 CN38 1,2,5,8 2 3 33 405 1350 20350 67500 CN46 1,4,5,8 2 4 39 366 1220 18300 61000 CN52 1,2,3,5,7 0 1 7 561 1870 28050 93500 CN58 1,2,4,5,7 0 2 13 522 1740 26100 87000 CN61 1,2,4,6,8 0 2 13 522 1740 26100 87000 CN50 1,2,3,4,6 1 1 13 522 1740 26100 87000 CN51 1,2,3,5,6 1 2 20 483 1610 24150 80500 CN57 1,2,4,5,6 1 2 20 483 1610 24150 80500 CN62 1,2,4,7,8 1 2 20 483 1610 24150 80500 CN53 1,2,3,5,8 1 2 20 483 1610 24150 80500 CN59 1,2,4,5,8 1 3 26 444 1480 22200 74000 CN66 1,2,3,4,6,7 0 0 0 600 2000 30000 100000 CN64 1,2,3,4,5,7 0 1 7 561 1870 28050 93500 CN69 1,2,3,5,7,8 0 1 7 561 1870 28050 93500 CN71 1,2,4,5,6,8 0 2 13 522 1740 26100 87000 CN63 1,2,3,4,5,6 1 1 13 522 1740 26100 87000 CN65 1,2,3,4,5,8 1 2 20 483 1610 24150 80500 ¤ F = (NCH-CH + Nβ)*6.5 % ; HL(i) = HL(i) max * (100 - F) / 100 Prediction of contents of lindane in SWF environment after stop of all local uses 1.1.1990 4 3.5 3 Water ng/L 2.5 2 1.5 Fish ng/g 1 Soil ng/g 0.5 Sedim. ng/g 0 1990 91 92 93 94 95 96 97 98 99 2000 400 350 ug/L KemR 5 OC 300 250 LC50 / fish 200 150 OH O2N CH3 SWF 20 OC 100 DNOC 50 NO2 PNEC / fish 0 0 2 4 6 8 10 12 14 16 18 20 Months FATEMOD level IV concentratios in water after stop of early May application of 10 Kg DNOC per hectare on plants (0.7 % was leached to water) in SWF and KemR areas of SouthWest and North Finland. Guideline determination for industrial emission Industrial discharge to Coastal Bothnian Bay Waste water stream (WS) Recipient Sea Area (RSA) Ar(1,2,3) = 1E+6 (=1000000) m2 HT(1)=500, HT(2) =10, HT(4)=0.01 m GA(1)=2.5E+7, GA(2)=2.86E+5, GA(4)=0.2 m3 h-1 GRA(1)=20, GRA(2) =35, GRA(4)=50000 h OCFr(4) = 0.04 AR(1,2,4) = 31250 m2 HT(1)=100, HT(2)=3, HT(4)=0.01 m GA(1)=3125000, GA(2)=4167, GA(4)=0.00625 m3 h-1 GRA(1)=1, GRA(2)=22.5, GRA(3)=50000 h OCFr(4) = 0.06 CF 3 The process chemicals emitted to the waste stream --------- Cl H 3CSO2 IFT O CBz CBz IFT IFT DKN DKN t C 5 20 5 20 5 20 -1 ug L C O C CH C DKN CBz Values of ecotoxicity Toxic level --> Code Cmpound CBz Chlorobenzene IFT Isoxaflutole DKN Diketonitrile RE determination Code PEC O Daphnia LC50 PNEC Fish LC50 PNEC Algae LC50 PNEC mg L-1 ug L-1 mg L-1 ug L-1 mg L-1 ug L-1 5.8 580 22.0 1.7 1.7* 2200 170 170 12.5 0.33 0.33* 1250 33 33 Daphnia Ro RE Kg h Fish Ro -1 Algae RE Kg h Ro -1 RE Kg h-1 2.319 0.004 250 0.0011 949 0.001855 539 2.229 0.00384 260 0.0010 987 0.001783 561 2.529 0.0149 67 0.076636 13 1.566 0.0092 109 0.047455 21 3.458 0.0203 49 0.104788 10 3.386 0.0199 50 0.102606 10 * Assumed toxicity for DKN was the same as for its precursor IFT PEC = the modelled stationary state concentration in water ("Predicted Environmental Concentration") -1 Risk ratio Ro = PEC / PNEC (for emission to the first waste basin Eo = 1 Kg h ) Risk emission RE = 1 / R (Kg h -1 to the first waste basin) N Conclusions: Guideline values for highest allowable discharges to the waste stream GE = lowest RE value divided by the safety factor (10) for each waste compound: CF 3 Cl H 3CSO2 IFT O CH C O CBz GE for CBz 25 C N C DKN GE for IFT(stable metabolite DNK incl.) 1 kg h-1 BIBI BIoaccumulation via Benthic Invertebrates SEDIMENT (1) COC = CON(1) / OCFR SWR BENTHIC INVERTEBRATES (3) CON(3) = SWR x COC x LFR(3) SWR WATER (2) CON(2) = SWR x COC / Kow K1(5) KD(4) K1(4) FIRST CONSUMER (4) CON(4) = * (i=4) KD(5) SECOND CONSUMER CON(5) = * (i=5) (5) K2,KE, KG,KM *CON(i) = (K1(i)XCON(2)+KD(i)xCON(i-1))/(K2(i)+KE(i)+KG(i)+KM) mg/cm 3 Fate of TeCP in SWF soils; model SOIL/CemoS pH 5.5 Concentration profiles 20 years after OC =0.05 initial contamination of 10 cm 45 40 topsoil layer 100 mg / cm 35 3 pH 6.0 OC =0.05 30 25 pH 6.5 OC = 0.05 20 15 pH 6.0 OC = 0.01 pH 6.5 OC =0.01 10 5 Depth m 0 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 11 Pentachlorophenol in worms (Aporrectoea) of South-West Finland soil originally contaminated by 100 ug/g dw 10 9 8 CWURM ug/g ww 7 6 5 4 3 Time years with no further contamination 2 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 Why you dont like rak, fresh Norrland w orms? VPLEST, WATSOLU, TDLKOW and LEVEL3+ predicted that they contain too much M alathione !