RESEARCH PROGRESS ON ECOTOXICOLOGY 



PART 1 



SINGLE SPECIES TESTS 



Donald I. Mount 



While research on and testing of single species have involved (in varying degrees) 

 wild mammals, reptiles, and amphibians, most effort has been directed towards 

 aquatic life and birds. Far more environmental toxicology resources have been 

 expended on aquatic life, perhaps because early environmental control efforts almost 

 exclusively focused on water pollution abatement. Only more recently have air and 

 terrestrial pollution abatement become increasingly important. Undoubtedly, the 

 extreme sensitivity of aquatic organisms to many of the early insecticides and their 

 rather high exposure to direct spraying and runoff made them among the first to 

 show obvious harm. 



The following highlights from the 1970s decade of progress in single species testing 

 are concentrated mainly on aquatic life and to a lesser extent on birds. Many of the 

 future milestones achieved will probably occur in wild mammal and other terrestrial 

 groups if present trends in atmospheric pollution (such as acid rain) continue. 



STATE OF THE ART IN 1970 



Acute Tests 



Until 1970 most of the small number of laboratories doing research on 

 environmental toxicology had been concentrating on acute tests consisting of single 

 doses for birds and mammals or short-term static exposures for aquatic animals. 

 Analytical techniques were primitive compared to today's methods. Few attempted 

 to confirm exposure with chemical measurements. Budgets were small and only 

 public agencies and universities were active. Only a handful of industries had 

 environmental toxicologists, and their combined effort was small. 



During the early part of the 1 960s (and even before), most attention was focused on 

 the effects of low dissolved oxygen (D.O.), metals, cyanide and domestic sewage on 

 aquatic life. With the expanded use of chlorinated hydrocarbon insecticides and 

 organophosphates, research on aquatic life effects shifted mostly to these contami- 

 nants. The impacts of these insecticides, mostly the chlorinated organic ones, 

 stimulated much of the early work on bird toxicology, an emphasis that exists even 

 today. 



Test Methods 



Much of the effort had to be focused on the development of toxicity test methods. 

 There was little available experience to draw upon for keeping thriving populations 

 of birds in laboratory conditions. M ost interest and concern centered on the effects of 



The Author. Dr. Mount is currently senior Research Aquatic Biologist, U.S. Environmental Protection 

 Agency, Duluth, Minnesota. He has published extensively on bioassay procedures and is a foremost 

 authority on the subject. 



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