tailieunhanh - WATER POLLUTION BY INSECTICIDES IN AN AGRICULTURAL RIVER .BASIN. I. OCCURRENCE OF INSECTICIDES IN RIVER AND TREATED MUNICIPAL WATER

Over the past decade, pollutant trading has been suggested as an economical means to address some of the nation’ s remaining pollution problems. Recent amendments to the Clean Air Act, for example, specifically authorize air emissions trading. Trading’ s potential to reduce the cost of meeting point and nonpoint source water pollution standards has also received increasing attention in recent years. Under such a trading scheme, dischargers faced with differing costs for meeting. | WATER POLLUTION BY INSECTICIDES IN AN AGRICULTURAL RIVER BASIN. I. OCCURRENCE OF INSECTICIDES IN RIVER AND TREATED MUNICIPAL WATER H. Page Nicholson Alfred R. Grzenda Gerald J. Lauer William S. Cox and John I. Teasley . Department of Health Education and Welfare Public Health Service Division of Water Supply and Pollution Control Region IV Atlanta Georgia ABSTRACT Insecticide contamination was studied in a stream from the summer of 1959 through the winter of 1962-63. The stream drains a 400-square-milc 1 036-krn2 watershed in northern Alabama in which approximately 15 000 acres 6 070 ha of cotton are cultivated annually. Estimates of insecticide usage on cotton varied from 58 000 lb technical metric tons in 1960 to 139 000 lb metric tons in 1962. Toxaphene DDT and BHC benzene hcxachloride comprised over 90 of the insecticides used. Water was sampled by the carbon adsorption method at a municipal water treatment plant. The data are reported as concentrations of insecticide recovered. DDT was never detected but toxaphene and BHC were detected in all samples. Toxaphene ranged from 7 to 410 parts per trillion ppt and BHC from 7 ppt to part per billion ppb . Samples of treated and untreated water showed that the purification process failed to remove toxaphene and BIIC. Samples taken in the summer of 1960 from the stream system indicated the same order of contamination observed at the water treatment plant. The data suggest that soil-persistent insecticides in the stream are related to levels of usage and to the solubility of the compounds. INTRODUCTION Certain insecticides have been recovered from the major waterways of the United States. Middleton and Lichtenberg 1960 detected DDT in the Mississippi River at Quincy Illinois and at New Orleans in the Missouri River at Kansas City and in Lake St. Clair and the Detroit River. They detected aldrin in a sample from the Snake River near Pullman Washington. Other evidence suggests the occurrence of a large .

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