Benzotrichloride

98-07-7

Colourless to yellowish liquid.

Penetrating odour.

195.48

Due to the rabid hydrolysis of benzotrichloride in water,
volatilization from water is not expected to be important
(Howard 1989).

Benzotrichloride is a liquid which fumes in air and has a
relatively high vapor pressure; therefore eporation from dry
surfaces may be expected to occur (Merck Index 1983).

Due to the rapid hydrolysis of benzotrichloride in water,
leaching in moist soils should not be significant, due to its
degradation to benzoic and hydrochloric acid (Howard 1989).

Hydrolyzes rapidly in water (Mabey & Mill 1978).

The ultraviolet adsorption spectrum for benzotrichloride in
methanol solution shows virtually no adsorption above 290 nm,
therefore direct photolysis in the environment is not expected
to occur (Sadtler 1966).

The vapor-phase reaction of benzotrichloride with
photochemically produced hydroxyl radicals in the atmosphere at
25 °C has an estimated half-life of 2 days at a hydroxyl
radical concentration of 8x10+5 mol/m3 (GEMS 1986).

Photooxidation half-life in air:
72.4d - 7.24d, scientific judgement based upon an estimated
rate constant for vapor phase reaction with hydroxyl radicals
in air (Howard 1991).

Benzotrichloride hydrolyzez in the presence of moisture,
forming benzoic acid and hydrochloric acid (Merck Index 1983).

The hydrolysis rate constant at 25 °C and pH 7 is reported to be
0.063 sec-1 which corresponds to a half-life of 11 sec.

(Mabey & Mill 1978).

The hydrolysis rate constant at 5.10 °C was found to be 0.00387
sec-1, which corresponds to a half-life of 3.0 minutes.

(Laughton & Robertson 1959).

First-order hydrolysis half-life:
11s, based upon overall rate constant (kh=6.3X10-2) at pH 7 and
25 degrees Celcius.
3min, based upon overall rate constant (kh=3.87X10-3) at pH 7
and
5 degrees Celcius.

Howard 1991

Aerobic half-life:
7d - 1d, scientific judgement based upon limited aqueous 
screening test data (Howard 1991).

Anaerobic half-life:
4w - 4d, scientific judgement based upon estimated unacclimated 
aqueous aerobic biodegradation half-life (Howard 1991).

Degradation observed in the Modified OECD Screening Test (95%
elimination of DOC in 3 days, 100% mineralization of
organochlorine in 1 day) is most likely degradation of
benzotrichloride's hydrolysis product, benzoic acid, since
benzotrichloride has estimated half-life of 11 sec in water at
25 °C and pH 7 (Steinhaeuser et al. 1986).

Confirmed to be biodegradable (Anon. 1987).

Based on the log Kow, the BCF for benzotrichloride can be
estimated to be 98. 
Due to the rapid hydrolysis of
benzotrichloride in water, bioconcentration in aquatic
organisms is not expected to occur (Lyman et al. 1982).

Toxicity threshold (cell multiplication inhibition test):
Bacteria (Pseudomonas putida): > 100 mg/l
(Bringmann & Kühn 1980).

Toxicity threshold (cell multiplication inhibition test):
Green algae (Scenedesmus quadricauda): > 100 mg/l
Protozoa (Entosiphon sulcatum): 56 mg/l
Protozoa (Uronema parduczi: > 80 mg/l
(Bringmann & Kühn 1980).