A toxicity identification evaluation (TIE) was conducted on the effluent from a petrochemical plant which discharges into an estuary. The effluent had been consistently toxic to mysid shrimp (Mysidopsis bahia) but not toxic to sheepshead minnows (Cyprinodon variegatus). Phase I effluent toxicity characterization tests revealed that treatment of the effluent with a cation exchange resin (Amberlite(R) IR-120 Plus) was partially effective at reducing, but not removing, toxicity. Phase II characterization tests revealed that four cations varied with toxicity: Ca and Sn were positively correlated with increasing toxicity; Mg and K were negatively correlated with increasing toxicity. Toxicity tests with SnCl2 revealed that the toxicity threshold for Sn was far above the concentrations present in the raw effluent. Reduction of Ca was shown to result in a significant improvement in survival, but some toxicity still remained. Further augmentation of the treated effluent with CaCl2, MgCl2, and KBr to restore the concentrations of Ca, Mg, K, and Br to natural seawater concentrations resulted in survival of all exposed organisms. Repeated success of this treatment regime on additional samples of the effluent as well as "mock effluent" studies confirmed that ion imbalance was the sole source of toxicity in this effluent. Process source water composition and essential ion balance are discussed as important components of marine effluent TIEs.
some l,2-epoxy-2-methyipropane (8%) was also present. For the case of 1-butene the epoxide mixture consisted largely of 1,3-and 2,3-epoxybutanes as well as some ethylene and propylene oxides. No 1,2-epoxybutane was found.
: Large quantities of trap and skeet clay targets are used in shooting activities around the United States. For example, the number of targets used since 1970 has averaged approximately 560 million a year. A number of acute and chronic tests were performed to determine the toxicity of Remington Arms Company Blue Rock(®) trap and skeet target fragments upon selected freshwater and marine organisms. These studies were undertaken in support of an environmental impact study of trap and skeet shooting activities at a major gun club in the northeast United States. Targets were composed of approximately 67% dolomitic limestone, 32% petroleum pitch and 1% fluorescent aqueous paint (painted targets only). The majority of samples were painted, new targets obtained from the manufacturer and painted and aged targets collected around a shooting range. Additional tests were conducted using non-painted, new targets and leachates prepared from both painted, new and aged targets. Targets were crushed to small fragments and were either directly added to the test vessels at extremely high concentrations ranging from 670 to 600 000 mgl(-1) or used in leachate tests. In direct tests all target materials were essentially non-toxic to marine and freshwater organisms, except for the non-painted new targets which exhibited minimal acute toxicity to Daphnia magna (48 h EC 50=2200 mgl(-1)). In leachate tests, the leachate was not-toxic to mysid shrimp, the only organism tested. Additional samples of crushed targets were analysed for the presence of selected priority pollutants (EP toxicity test) and polycyclic aromatic hydrocarbons (PAHs). The targets did not exhibit the characteristics of toxicity as determined by the EP toxicity test but did contain substantial amounts of PAHs. However, results from new and aged targets suggest that PAH are tightly bound in the petroleum pitch and limestone matrix and are unlikely to be readily available in the environment. The potential impact of targets on the environment is further discussed.
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