Physical Properties
Molecular weight:271.9; Physical form:Colourless crystals. Melting point:209-210 °C; Vapour pressure:3 ×10-3 mPa (23 °C); Partition coefficient(n-octanol and water):logP = 3.01; Solubility:In water 2.5 mg/l (25 °C). In acetone 8.3, benzene 16.8, dioxane 14.1, ethyl alcohol 1.1, tetrahydrofuran 19.3 (all in g/l, 25 °C).; Stability:Stable for 12 h at pH 2 (2.5 ppm aq. solution); in weak alkali, DT50 c. 10 d ( pH 6.8, 5-10 °C, 2.0 ppm aq. solution);
Environmental Profile
Ecotoxicology:
Algae: EC50 (96 h) for Selenastrum capricornutum >1000 mg/l.Bees:Non-toxic to bees; LD50 (contact) >0.4 mg/bee.Birds:No effect on hens fed 1.5 mg/ kg for 7 days, and for another 3 days at 15 mg/ kg.Daphnia: LC50 (3 h) >40 ppm.Fish: LC50 (48 h) for young carp >320 mg a.i. (as tech. or DP)/l, 135 mg a.i. (as 50% WP)/l.Worms: LC50 (14 d) >2000 mg/ kg substrate.
Environmental fate:
Animals:In rats, principal metabolites are 2-hydroxymethyl-3,4,5,6-tetrachlorobenzoic acid and its oxidation products.Soil:Principal metabolites in soil are 2-hydroxymethyl-3,4,5,6-tetrachlorobenzoic acid and its oxidation products (K. Aoki et al., Jpn. Pestic. Inf., 1979, 36, 32).Plant:4,7-Dichlorophthalide and 4,6,7-trichlorophthalide are formed in rice. WATER SOLUBILITY: 2.49 ppm at 25°