172 GEHRS 



sunfish (Parkhurst, Gehrs, and Rubin, 1978), and benzo(a)pyrene is a 

 potent mutagen and carcinogen, whereas benzo(e)pyrene is virtually 

 inactive. 



The complexity of developing a program for evaluating the 

 environmental hazards of coal conversion is obvious. It is apparent 

 that such a program should incorporate toxicity screening of 

 effluents and their chemical fractions, but it is less apparent how to 

 develop an approach that will produce the data necessary for 

 predictive capabilities (research using individual compounds). 



Generating a manageable approach to such a large number of 

 contaminants requires adopting the same philosophy that produced 

 the screening approach, i.e., look first for the greatest commonalities 

 among the various compounds. This allows us to arrange compounds 

 in groups that are most similar in certain parameters (e.g., structure). 



Herbes, Southworth, and Gehrs (1977), adopting such a 

 philosophy and arranging the compounds according to structure and 

 molecular weight, were able to conduct research of a predictive 

 nature for all coal conversion effluents by using approximately 30 

 compounds rather than the thousands present. This is clearly a more 

 manageable number. 



SUMMARY 



In summary, the term coal conversion refers to any of a group of 

 processes designed to produce liquid, gaseous, or clean-burning 

 solid fuels from coal. All the processes use high temperature and high 

 pressure (often in a reducing atmosphere) to produce the fuel and 

 give rise to a myriad of organics that may ultimately find their way 

 into aquatic environments. Hundreds, perhaps thousands, of 

 individual compounds may be present in aqueous effluents. 

 Investigation of the potential for environmental impact of these 

 effluents can be approached in one of two ways, each of which 

 possesses weaknesses. The two approaches are testing the whole 

 complex effluent or testing individual compounds. The first provides 

 rapid data on toxicity but has little value for predictive purposes 

 since neither the identities nor concentrations of materials are known. 

 The second, testing individual compounds, provides the necessary 

 data for developing predictions. To study all the various compounds 

 (including isomers of each) and all their combinations with respect to 

 effects, transport, transformation, fate, and food chain kinetics and 

 including all the environmental factors that might affect these 

 parameters would require a substantial percentage of the Gross 

 National Product and more time than is available. Obviously the 



