ABSTRACT
Benzoic acid (10.0 wt % at 32 °C) and paraffin (2.0 wt % at 28 °C) (Monsanto, 1960). Solubility in water (µg/L): 54 (Monsanto, 1974) 50 at 20 °C (Nisbet and Sarofim, 1972) 60 at 24 °C (shake flask-nephelometry, Hollifield, 1979) Vapor pressure (x 10-4 mmHg): 4.94 at 25 °C (quoted, Mackay and Wolkoff, 1973) 0.6 at 38 °C (Nisbet and Sarofim, 1972) 3.7 at 37.8 °C (calculated, Monsanto, 1960) 1.835 at 25 °C (estimated using GC retention data, Foreman and Bidleman, 1985) Environmental fate: Biological. Reported degradation products by the microorganism Alcaligenes BM-2 for a mixture of polychlorinated biphenyls include monohydroxychlorobiphenyl, 2-hydroxy-6oxochlorophenylhexa-2,4-dieonic acid, chlorobenzoic acid, chlorobenzoylpropionic acid, chlorophenylacetic acid, and 3-chlorophenyl-2-chloropropenic acid (Yagi and Sudo, 1980). When PCB-1248 (5 and 10 mg/) was statically incubated in the dark at 25 °C with yeast extract and settled domestic wastewater inoculum, no biodegradation was observed (Tabak et al., 1981). Chemical/Physical. Heating PCB-1248 in oxygen at 270-300 °C for 1 wk resulted in the formation of mono-, di-, tri-, tetra-, and pentachlorodibenzofurans (PCDFs). At temperatures greater than 330 °C, PCDFs decompose (Morita et al., 1978). PCB-1248 will not hydrolyze to any reasonable extent (Kollig, 1993). When PCB-1248 was heated up to 315 °C in a closed system, no appreciable decomposition was observed (Monsanto, 1960). Mackay and Wolkoff (1973) estimated an evaporation half-life of 58.3 min from a surface water body that is 25 °C and 1 m deep. Exposure limits: Potential occupational carcinogen. NIOSH REL: TWA 1.0 g/m3, IDLH 5 mg/m3. Toxicity: LC50 (5-d) for rainbow trout 54 µg/L (Johnson and Finley, 1980). LC50 (96-h) for bluegill sunfish 690 µg/L, cutthroat trout 5,750 µg/L, channel catfish >100 µg/L, yellow perch >100 µg/L (Johnson and Finley, 1980). Acute oral LD50 for rats 11 g/kg (quoted, RTECS, 1985). Drinking water standard (final): For all PCBs, the MCLG and MCL are zero and 0.5 µg/L, respectively (U.S. EPA, 2000). Uses: In epoxy resins to improve adhesion and resistance to chemical attack; as an insulator fluid for electric condensers and as an additive in very high pressure lubricants. In fluorescent and highintensity discharge ballasts manufactured prior to 1979 (U.S. EPA, 1998). PCB-1248 and PCB-1254 were used instead of silicone oils in vacuum pumps (Monsanto, 1960). At a concentration of 5 to 25 wt %, increased the effective kill-life of the lindane spray up to 10 times. May have been used in chlordane and BHC insecticide formulations (Monsanto, 1960).
