PW03 QSAR
Exhibit Hall
8:00 AM - Wednesday
(PW030) Initial Risk Assessment of 4-Methylbenzenesulfonyl chloride in Environment.
Bae, Heekyung1, Kim, Mi-Kyoung1, Kim, Su-Hyon1, Yang, Junyong1, Koo, Hyunju1, Jung, Sangwon, Kim, Hyun-Mi1, Jeon, Sung-Hwan1, Choi, Kwang-Soo1, Na, Jin-Gyun1, Rhee, Deok-Gil1, 1 National Institute of Environmental Research, Incheon, Korea
ABSTRACT- - 4-Methylbenzenesulfonyl chloride is produced about 542.7 tons/year in Korea and is imported 689.8 tons/year into Korea from China as of 2001 survey. The substance is produced as a by-product in reaction of HSO3Cl and toluene in food additive industry and this chemical is used as a source of foaming agent in plastic and rubber industry, of riboflavin and antithrombotic drug in pharmaceutical industry and of condensing agent in dye industry. In this study, Quantitative Structure-Activity Relationships (QSAR) is used for getting information on the physical-chemical properties of this chemical. In addition, hydrolysis in water, acute toxicity to aquatic and terrestrial organisms were studied. The physical-chemical properties of 4-methylbenzenesulfonyl chloride were estimated as followed. ; vapor pressure ; 1mmHg at 88oC, Henry's Law constant ; 9.67 x 10-6 atm-m3/mole at 25oC. Water solubility and partition coefficient n-octanol/water are not applicable due to rapid hydrolysis. 4-Methylbenzenesulfonyl chloride was hydrolyzed to 4-methylsulfonic acid and half-lives(t1/2) at 25oC in water were 2.2 min at pH 4, 2.2 min at pH 7 and 2.6 min at pH 9. The substance was not readily biodegradable by 17.7 % as BOD after 28 days. The calculated half-life of photochemical-oxidative degradation in the atmosphere by OH radicals is 8.7 days and environmental fate of 4-methybenzenesulfonyl chloride was estimated by EPIWIN modelling. According to the fugacity model level III, 4-methybenzenesulfonyl chloride was mainly distributed into soil (66.4%) and water (28.4%), and small amounts were into air (3.81%) and sediment (1.32%). The calculated BCF value of the substance was 96.9, so it is expected that it has a low potential for bioaccumulation. The toxicity data for the aquatic organisms are as follow. 72 hr-EC50 (growth rate) for algae was >100 mg/L, 48 hr-EC50 for daphnia was 70 mg/L and the 96 hr-LC50 of acute toxicity to fish was 55 mg/L. 4-Methylbenzenesulfonyl chloride was hydrolysed to 4-methylsulfonic acid, which is a strong acid (pK =-1.34) and is completely dissociated in the environmental pH. According to the acute toxicity value of 4-methylbenzenesulfonyl chloride, its adverse effects on the aquatic environment are not expected.
Key words: initial risk assessment, 4-methylbenzenesulfonyl chloride, physical chemical properties, ecotoxicity