| Abstract
| - To predict the persistency of a chemical in the environment,the chemical's physical−chemical properties and itsreactivity in the environment need to be known or at leastestimated. The partitioning of a chemical can be describedon the basis of its water solubility, its octanol/waterpartitioning coefficient, and its vapor pressure. Themechanisms by which a chemical can be transformedmay be categorized as being hydrolysis, oxidation, reduction,and photolysis. This study establishes a method forestimating the relative susceptibility of some potentialenvironmental pollutants to undergo hydrolysis reactions.The method used the second-order rate constant for thereaction with sodium methoxide in methanol/N,N-dimethylformamide (DMF) as an indicator of relativesusceptibility toward hydrolysis. The decabromodiphenylether is rapidly hydrolyzed, that is, undergoes nucleophilicaromatic substitution, while the rate of reaction of lessbrominated diphenyl ethers decreased by roughly a factorof 10 for each decrease in the level of bromination.Hexachlorobenzene was found to have a similar rate to anonabromodiphenyl ether. 2,2-Bis(4-chlorophenyl)-1,1,1-trichloroethane (DDT) was transformed to 2,2-bis(4-chlorophenyl)-1,1-dichloroethene (DDE) immediately underthese conditions, while DDE showed no apparent reaction.The results show that chemicals that can undergo eliminationreactions are rapidly transformed, as are perhalogenatedchemicals that can undergo substitution reactions.These chemicals are not likely to persist in the environment,while those that did not show any observable reactivityunder similar hydrolytic conditions may persist for a verylong time.
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