Pesticide Contamination of Surface Waters by Sugar Cane Farming in Louisiana

Abstract

Agricultural, hyrological, and water quality studies were conducted in Louisiana during the years 1961, 1962, and in 1964 to determine the methods, extent, and duration of surface water contamination by endrin used in sugar cane agriculture. In 1961, a maximum of 360 parts per trillion (ppt) of endrin was recovered from water by carbon adsorption (sample volrunes of 1,000 to 5,000 gallons). Endrin was recovered from each of the six streams sampled, indicating that its use resulted in contamination of adjacent streams. Three of the streams were sampled at sites of fish kills attributed to endrim Endrin was also recovered from the water of treatment plants utilizing two of these streams as sources of supply. In 1964, use of a more efficient carbon adsorption sample size of 100 gallons resulted in a maximum recovery of 700 ppt endrin while up to 820 ppt were obtained from 1-gallon grab samples.Surface runoff from fields was the main source of endrin contamination. Largest recoveries from the streams occurred after the first precipitation and runoff following applications to the fields. After that amounts recovered dropped rapidly. Residuals of endrin persisting in the soil frown one agricultural season to the next may contribute small quantities to the water whenever runoff occurs.In addition to endrin, pesticides not used in sugar cane agriculture including dieldrin, BHC, and DDT were recovered from surface waters. Concentrations of dieldrin up to 1,360 ppt, BHC to 73 ppt, and DDT to 24 ppt were recovered.

Pesticides in agricultural runoff and their effects on downstream water quality

“…Toxicity tests of pesticides on aquatic species are usually made in clean, sediment-free water. The relationship between the results of these tests and the effects of various concentrations of pesticides on aquatic species present in lakes and streams that contain dissolved salts and suspended solids is not always straightforward [25]. Even though a number of direct and indirect effects of different pesticides on organisms in various aquatic environments has been reported [26], changes caused by chronic exposure of aquatic organisms to low concentrations of pesticides are difficult to assess because of the great variability and natural complexity of aquatic ecosystems.…”

Review: Pesticides in Agricultural Runoff and Their Effects on Downstream Water Quality

“…Toxicity tests of pesticides on aquatic species are usually made in clean, sediment-free water. The relationship between the results of these tests and the effects of various concentrations of pesticides on aquatic species present in lakes and streams that contain dissolved salts and suspended solids is not always straightforward [25]. Even though a number of direct and indirect effects of different pesticides on organisms in various aquatic environments has been reported [26], changes caused by chronic exposure of aquatic organisms to low concentrations of Table 4 for explanation of symbols.…”

Residue Reviews

“…The residual chlorine demand increased, 2,4-D and 2,4,5-T were found, and free phenol decreased over 92 days when granules were used, but increased with liquid formulations, again probably as a result of slow release from granules and perhaps sorption out of the system. Large scale use of insecticides was shown to contaminate surface water in Louisiana by LAUER et al (1966) who analysed soil, water, and stream sediments in an area where two percent endrin pellets were used on 3,300 acres of sugar cane. In 1961 up to 360 p.p.t.…”

“…The removal and degradation of residues in food during harvesting, treating, cleaning, preparing, and cooking has been investigated, but again not in relation to granules. Residues in water supplies have been discussed above, and such studies as those of MoYE and LUCKMANN (1964), WEATHERHOLTZ et al (1967), LAUER et al (1966), andFAHEY et al (1968) are valuable in this respect. In a study of the distribution of pesticides in California, where about 20 percent of all pesticides in the United States are used, BAILEY and HANNUM ( 1967) related the concentration of pesticides in water, sediments, and aquatic organisms to local agricultural practices and rainfall runoff.…”