uptake, transfer within tissues and organs, and the mechanisms that permit certain 

 organisms to accumulate these compounds without apparent toxic effects. 



Despite significant advances in instrumentation during the seventies, researchers 

 are still seriously handicapped by their inability to detect and accurately measure 

 small amounts of organic compounds in the estuarine environment. Virtually all 

 experimental studies on the impact of organics on estuarine species have been con- 

 ducted under laboratory conditions using either static or flow-through systems that 

 rely on conventional dilution techniques to arrive at the lower levels of concentra- 

 tion. While laboratory studies establish basic physiological responses of individual 

 species to particular compounds, laboratory conditions do little more than simulate 

 the natural environment. Reliable information is still unavailableeither on the levels 

 of compounds in estuarine systems or on how these levels affect a variety of biolog- 

 ical responses within the organisms. 



The significance of the impact of toxic organic compounds on the estuarine and 

 marine environments cannot be overestimated, because these areas provide protein 

 for the expanding populations of the world. The 1976 FAO World Conference on 

 Aquaculture concluded that a five- to ten-fold increase in production of fisheries 

 products from aquaculture would be possible by the year 2000, given adequate 

 financial and technical support. Although limited investment and technical support 

 are now making such an increase unlikely, increasing pollution of freshwater ponds 

 and coastal waters are a far more serious threat ( Barney, 1 980). The expanded use of 

 pesticides is expected to increase water pollution in many of the developing coun- 

 tries, where the more persistent pesticides are likely to be in continued use. Pesticide 

 use in the developing countries may well quadruple between now and the year 2000 

 (Barney, 1980). According to the Global 2000 Study, pollution of coastal ecosystems 

 is likely to increase. The study indicates that 60 to 80 percent of the valuable commer- 

 cial marine species are dependent upon estuaries, salt marshes, or mangrove swamps 

 for a habitat during their life cycle. As cities expand and industries develop estuarine 

 and coastal wetland areas, the fragile environments on which these commercially 

 important species depend will deteriorate. 



Perhaps the greatest challenge of the eighties will be to communicate to local 

 governments in a number of countries the importance of estuarine and coastal areas 

 and how toxic organic compounds can destroy their productivity. Currently, there 

 appears to be little concern, despite the 1972 Coastal Zone Management Act and 

 coastal management laws later enacted by a number of states. Without proper recog- 

 nition of the impact of toxic organic compounds on the productivity of coastal areas 

 by local and state governments, accompanied by intelligent planning that prevents 

 further contamination of these areas, the prospect for continued productivity of 

 these areas is extremely dim. 



REFERENCES 



Armstrong, D.A., D.V. Buchanan, M.H. Mallon, R.S. Caldwell, and R.E. Millemann. 1976. 



Toxicity of the insecticide methoxychlor to the Dungeness crab Cancer magister. Mar. Biol. 



38:239-252. 

 Bahner. L.H., and D.R. Nimmo. 1976. Metals, pesticides, and PCB's: toxicities to shrimp 



singlv and in combination. In: Estuarine processes, vol. I., M. Wiley, ed. Academic Press. 



NY. pp. 523 532. 

 Barney, G.O. 1980. The global 2000 report to the president: entering the twenty-first century. A 



report prepared bv the Council on Environmental Quality and the Department of State. 



vol. 1. 

 Bookhout. C.G., and J.D. Costlow, Jr. 1975. Effects of mirex on the larval development of blue 



crab. Water. Air, and Soil Pollution 4:1 13-126. 

 Bookhout, C.G., J.D. Costlow. Jr., and R. Monroe. 1976. Effects of methoxychlor on larval 



development of mud crab and blue crab. Water, Air, and Soil Pollution 5:349-365. 

 Bookhout. C.G., J.D. Costlow. Jr.. and R. Monroe. 1980. Kepone effects on larval develop- 

 ment of mud crab and blue crab. Water. Air, and Soil Pollution 13:57-77. 



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