p,p′-DDE

Cl Cl CASRN: 72-55-9; DOT: 2761; DOT label: Poison; molecular formula: C14H8Cl4; FW: 319.03; RTECS: KV9450000 Physical state, color, and odor: White, crystalline, odorless powder Melting point (°C): 88-90 (Leffingwell, 1975) 89.8 (Plato and Glasgow, 1969) Diffusivity in water (x 10-5 cm2/sec): 0.46 at 20 °C using method of Hayduk and Laudie (1974) Entropy of fusion (cal/mol⋅K): 16.0 (Plato and Glasgow, 1969) Heat of fusion (kcal/mol): 5.800 (DSC, Plato and Glasgow, 1969) Henry’s law constant (x 10-3 atm⋅m3/mol): At 23 °C: 1.22 and 3.65 in distilled water and seawater, respectively (Atlas et al., 1982) 0.0417 at 25 °C (thermodynamic method-GC/UV spectrophotometry, Altschuh et al., 1999) 0.013 at 5 °C, 0.030 at 15 °C, 0.042 at 20 °C, 0.050 at 25 °C, 0.085 35 °C; in 3% NaCl solution:

0.040 at 5 °C, 0.058 at 15 °C, 0.165 at 25 °C, 0.189 at 35 °C (Cetin et al., 2006) 0.33 at 25 °C (gas stripping-GC, Jantunen and Bidleman, 2006) Bioconcentration factor, log BCF: 4.00-4.15 (fish tank), 7.26 (Lake Ontario) (rainbow trout, Oliver and Niimi, 1985) 4.71 (freshwater fish), 4.44 (fish, microcosm) (Garten and Trabalka, 1983) 4.91 (Oncorhynchus mykiss, Devillers et al., 1996) 4.72 (Crassostrea virginica, Schimmel and Garnas, 1981) 4.05 (green algae), 4.56 (snail), 4.77 (mosquito), 4.08 (Gambusia affinis) (Metcalf et al., 1975) 4.44 (Gambusia affinis, 33-d exposure, Metcalf et al., 1971) 4.91 (Oncorhynchus mykiss, 4-d exposure, Oliver and Niimi, 1985) Soil organic carbon/water partition coefficient, log Koc: 5.386 (Reinbold et al., 1979)

6.6 (average using 10 suspended sediment samples collected from the St. Clair and Detroit Rivers,

Lau et al., 1989) Kd = 2.5 mL/g (Barcelona coastal sediments, Bayona et al., 1991). Octanol/water partition coefficient, log Kow: 5.83 (Travis and Arms, 1988) 5.69 (centrifuge flask-GLC, Freed et al., 1977, 1979a) 5.766 (Kenaga and Goring, 1980) 5.89 (estimated using HPLC-MS, Burkhard et al., 1985a) 6.20 (estimated using HPLC, DeKock and Lord, 1987) 6.956 at 25 °C (shake flask-GLC, de Bruijn et al., 1989) Solubility in organics: Soluble in fats and most solvents (IARC, 1974) Solubility in water: 40 µg/L at 20 °C, 1.3 µg/L at 25 °C (Metcalf et al., 1973a) 14 ppb at 20 °C (extraction-GLC, Weil et al., 1974) 40 ppb at 20 °C (Chiou et al., 1977) 55 ppb at 15 °C, 120 ppb at 25 °C, 235 ppb at 35 °C, 450 ppb at 45 °C (particle size ≤5 µm,

Biggar and Riggs, 1974) 65 ppb at 24 °C (shake flask-nephelometry, Hollifield, 1979) 1.1 µg/L at 25 °C (generator column-HPLC/UV spectrophotometry, Swann et al., 1983) Vapor density: 109 ng/L at 30 °C (Spencer and Cliath, 1972) Vapor pressure (x 10-6 mmHg): 7.4 at 25 °C (GC, Wescott and Bidleman, 1981) 15.7 at 25 °C (estimated-GC, Bidleman, 1984) 7.4 at 25 °C (Wescott and Bidleman, 1981) 20.3 at 25 °C (subcooled liquid vapor pressure calculated from GC retention time data, Hinckley

et al., 1990) 6.49 at 30 °C (Spencer and Cliath, 1972) 13 at 30 °C (Wescott et al., 1981) Environmental fate: Biological. In four successive 7-d incubation periods, p,p′-DDE (5 and 10 mg/L) was recalcitrant to degradation in a settled domestic wastewater inoculum (Tabak et al., 1981). Photolytic. When an aqueous solution of p,p′-DDE (0.004 µM) in natural water samples from California and Hawaii were irradiated (maximum λ = 240 nm) for 120 h, 62% was photooxidized to p,p′-dichlorobenzophenone (Ross and Crosby, 1985). In an air-saturated distilled water medium irradiated with monochromic light (λ = 313 nm), p,p′-DDE degraded to p,p′-dichlorobenzophenone, 1,1-bis(p-chlorophenyl)-2-chloroethylene (DDMU), and 1-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-2-chloroethylene (o-chloro DDMU). Identical photoproducts were also observed using tap water containing Mississippi River sediments (Miller and Zepp, 1979). The photolysis half-life under sunlight irradiation was reported to be 1.5 d (Mansour et al., 1989). When p,p′-DDE in water was irradiated at 313 nm, a quantum yield of 0.3 was achieved. A photolysis half-life of 0.9 d in summer and 6.1 d in winter by direct sunlight at 40° latitude was observed. Photolysis products included DDMU (yield 20%), o-chloro DDMU (yield 15%), and a

for the photolysis of p,p′-DDE in hexane at wavelengths of 254 and 313 nm, respectively (Mosier et al., 1969; Zepp et al., 1977). Singmaster (1975) reported a photolytic half-life of 1.1 d when p,p′-DDE (0.84 µg/L) in San Francisco Bay, CA water was subjected to sunlight. When p,p′-DDE in a methanol solvent was photolyzed at 260 nm, a dichlorobenzophenone, a dichlorobiphenyl, DDMU, and 3,6-dichlorofluorenone (yield 10%) formed as the major products (Plimmer et al., 1970a). Chemical/Physical. May degrade to bis(chlorophenyl)acetic acid in water (quoted, Verschueren, 1983), or oxidize to p,p′-dichlorobenzophenone using UV light as a catalyst (HSDB, 1989). p,p′-DDE is resistant to hydrolysis. At pH 5 and 27 °C, the estimated half-life is >120 yr (Wolfe et al., 1977). This is in agreement with results reported by Eichelberger and Lichtenberg (1971). They found no change in p,p′-DDE concentration in water in an 8-wk period. In a buffered anaerobic aqueous solution, p,p′-DDE was transformed by powdered zero-valent iron at 20 °C with and without the surfactant Triton-Z-114. First-order degradation rates were 1.6 and 2.6/d without and with surfactant, respectively (Sayles et al., 1997). At influent concentrations of 1.0, 0.1, 0.01, and 0.001 mg/L, the GAC adsorption capacities were 232, 98, 42, and 18 mg/g, respectively (Dobbs and Cohen, 1980). Toxicity: EC50 (21-d) for Xenopus laevis >393 µM (Saka, 2004). LC50 (96-h) for rainbow trout 32 µg/L, Atlantic salmon 96 µg/L, bluegill sunfish 240 µg/L (Johnson and Finley, 1980), Xenopus laevis >393 µM (Saka, 2004). Acute oral LD50 for rats 880 mg/kg (quoted, RTECS, 1985). Source: Agricultural runoff degradation of p,p′-DDT (quoted, Verschueren, 1983). Uses: Military product; chemical research.