risks from the consumption of chlori nated water." Although the reactions of chlorine are complex, Bean speculated "it is possible that only one or two key re actions with a few key structural components will be required to explain the initiation of the reaction sequences involved." Obviously much work re mains to be done in this area before even the most important reactions of chlorine in natural environments can be reasonably understood. Aquatic ecosystems Because the discharge of chlorine into surface waters and the ocean damages aquatic organisms, some areas of the U.S. are seriously consid ering banning wastewater chlorination. The EPA is now working on chlorine water quality criteria for the protection of aquatic life. It is anticipated that draft chlorine criteria will be com pleted early this year. Presently, many regulators and environmental man agers feel sufficient research has been completed to identify the hazards of chlorination for aquatic life. This chlorination conference, how ever, highlighted the fact that a great deal is still unknown. Richard Vanderhorst of Battelle, Pacific Northwest
Laboratories performed a study that examined the effects of low level chlorination on open microcosms in Puget Sound, Washington. He found statistically significant differences in the rates of growth; however, the meaning of these findings is question able because the "systems were clearly in a growth phase and had not reached steady state at the experiment's con clusion." David Anderson of Envirotest (Redmond, Wash.) presented infor mation to show that the interaction of chlorination with nickel resulted in increased accumulation of nickel in rainbow trout. His data show how important it is to evaluate the inter action of chlorination with other chemicals known to have environ mental effects. An overview of the effects of chlo rine-produced oxidants and THMs on marine invertebrates was presented by Geoffrey Scott of Research Planning Institute (Meggett, S.C.). The mate rials he reviewed showed that many of the effects are irreversible and that the juvenile stages of the organisms are more sensitive than the adult stages. Scott also presented information on the bioconcentration of bromoform in American oysters.
Fava and Davis said that the "inte gration of marine biological research with identified technical needs could be one of the true progressive steps to achieve the benefits of chlorination while at the same time helping to pro tect sensitive environmental systems." An example is using marine organisms such as oysters to monitor for human pathogens in the effluent from waste treatment plants. Many investigators said that additional field experiments concerning the effects of chlorine on aquatic life are needed to confirm what has been learned in the laboratory. Fava and Davis pointed out the need for additional research when they said: "As the use of chlorine continues to grow, so does the potential for aquatic effects. Ignoring the problem is not the proper response from an intelligent society. Instead, we need to be pre pared to make educated technical de cisions based on experimentally proven facts—not on ignorance and unproven assumptions." The proceedings of the conference will be published this year by Ann Arbor Science (Mich.). The next chlorination conference is scheduled for October 1983 in the MarylandVirginia area. —Bette Hileman
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Environ. Sci. Technol., Vol. 16, No. 1, 1982
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