ABSTRACT

Cl Note: β-BHC is a steroisomer of γ-HCH, the active ingredient of lindane. CASRN: 319-85-7; DOT: 2761; DOT label: Poison; molecular formula: C6H6Cl6; FW: 290.83; RTECS: GV4375000 Physical state: Although β-BHC is a solid at room temperature, the odor threshold concentration is 0.32 µg/kg (Sigworth, 1964). Melting point (°C): 314.5 (quoted, Horvath, 1982) 311.7 (quoted, Standen, 1964) Boiling point (°C): 60 at 0.58 mmHg (quoted, Horvath, 1982) Sublimes at 760 mmHg (U.S. EPA, 1980a) Density (g/cm3): 1.89 at 19 °C (Weast, 1986) Diffusivity in water (x 10-5 cm2/sec): 0.50 at 20 °C using method of Hayduk and Laudie (1974) Henry’s law constant (x 10-7 atm⋅m3/mol): 4.41 at 25 °C (thermodynamic method-GC/UV spectrophotometry, Altschuh et al., 1999) 0.53 at 5 °C, 0.91 at 10 °C, 2.17 at 20 °C, 5.23 at 30 °C, 8.68 at 35 °C; in 3% NaCl solution: 1.09

at 5 °C, 1.48 at 15 °C, 2.76 at 25 °C, 4.24 at 35 °C (dynamic headspace-GC, Sahsuvar et al., 2003)

Bioconcentration factor, log BCF: 2.82 (brown trout, Sugiura et al., 1980) 3.08 (activated sludge), 2.26 (algae), 2.65 (golden ide) (Freitag et al., 1985) 2.86 (freshwater fish), 2.97 (fish, microcosm) (Garten and Trabalka, 1983) 3.17 (Brachydanio rerio, Devillers et al., 1996) Soil organic carbon/water partition coefficient, log Koc: 3.462 (silt loam, Chiou et al., 1979) 3.322 (Karickhoff, 1981) 3.553 (Reinbold et al., 1979)

at 19.8 and 30 °C, respectively (Mills and Biggar, 1969)

3.06, 3.17, 3.27, 3.41, 3.43, 3.50 (lateritic soil), 3.27, 3.38 (Kari soil), 3.26 (sandy soil), 3.29, 3.32 (alluvial soil), 3.50 (Pokkali soil) (Wahid and Sethunathan, 1979) Octanol/water partition coefficient, log Kow: 3.80 at 22 °C (shake flask-GLC, Kurihara et al., 1973) 3.842 at 25 °C (shake flask-GLC, de Bruijn et al., 1989) 3.87 at 45 °C (shake flask-GLC, Paschke and Schüürmann, 1998) 3.97 at 25 °C (shake flask-GLC, Paschke and Schüürmann, 2000) Solubility in organics: Soluble in ethanol, benzene, and chloroform (Weast, 1986) Solubility in water: 130, 200 ppb at 28 °C (0.1 µm particle size, Kurihara et al., 1973) 240 µg/L at 25 °C (extraction-GLC, Weil et al., 1974) 700 ppb at 25 °C (Brooks, 1974) 5 mg/L at 20 °C (Chiou et al., 1979) 2.7 mg/L at 20 °C (Mills and Biggar, 1969) Vapor pressure (x 10-7 mmHg): 2.8 at 20 °C (Balson, 1947) 4.66 at 25 °C (Banerjee et al., 1990) Environmental fate: Biological. No biodegradation of β-BHC was observed under denitrifying and sulfate-reducing conditions in a contaminated soil collected from the Netherlands (Bachmann et al., 1988). In four successive 7-d incubation periods, β-BHC (5 and 10 mg/L) was recalcitrant to degradation in a settled domestic wastewater inoculum (Tabak et al., 1981). Chemical/Physical. Emits very toxic fumes of chloride, HCl, and phosgene when heated to decomposition (Lewis, 1990). β-BHC will not hydrolyze to any reasonable extent (Kollig, 1993). Toxicity: EC50 (48-h) for Daphnia pulex 680 µg/L (isomeric mixture, Johnon and Finley, 1980 LC50 (96-h) values of 1.66, 1.52, and 1.10 mg/L for Poecilia reticulata, Brachydanio rerio, and Paracheirodon axelrodi, respectively (Oliverira-Filho and Paumgarten, 1997); for isomeric mixture: cutthroat trout 9 µg/L, rainbow trout 18 µg/L, goldfish 348 µg/L, fathead minnow 125 µg/L, channel catfish 105 µg/L, bluegill sunfish 67 µg/L, largemouth bass 41 µg/L (Johnson and Finley). LC50 (72-h) values of 2.18, 1.63, and 1.10 mg/L for Poecilia reticulata, Brachydanio rerio, and Paracheirodon axelrodi, respectively (Oliverira-Filho and Paumgarten, 1997). LC50 (48-h) values of 2.68, 1.63, and 1.10 mg/L for Poecilia reticulata, Brachydanio rerio, and Paracheirodon axelrodi, respectively (Oliverira-Filho and Paumgarten, 1997). LC50 (24-h) values of 3.14, 1.78, and 1.70 mg/L for Poecilia reticulata, Brachydanio rerio, and Paracheirodon axelrodi, respectively (Oliverira-Filho and Paumgarten, 1997). Acute oral LD50 for rats 6,000 mg/kg (quoted, RTECS, 1985). Use: Insecticide.