China
Africa
Explore chapters and articles related to this topic
Dislodgeable Foliar Residues of Pesticides in Agricultural, Landscape, and Greenhouse Environments
Published in Donald J. Ecobichon, Occupational Hazards of Pesticide Exposure, 2020
Gerald R. Stephenson, Gwen M. Ritcey
In their review of the citrus reentry problem, Gunther et al. (1977) pointed out that it was primarily a problem associated with the use of the insecticide parathion in citrus production. Although worker illnesses associated with parathion use in California citrus groves were increasingly common during the 1970s (Popendorf and Leffingwell 1982), such reports were very rare in Florida. An early and important discovery was that of Spear et al. (1978) who showed that parathion degraded to its more toxic and more persistent paraoxon analogue on citrus foliage. In Florida, DFRs of both parathion and paraoxon were dissipated quite rapidly by rainfall (Nigg, Allen, and King 1979). In contrast, the dry, rainfree, dusty conditions in California were related to higher rates of paraoxon production and greater paraoxon persistence (Popendorf and Leffingwell 1978) and thus the need for longer reentry times. Adams, Iwata, and Gunther (1976) showed that, in California, even soil type and the type of dust landing on citrus foliage could influence the persistence of DFRs for both parathion and paraoxon. In studies conducted in Florida citrus groves on the nonpersistent malathion, Nigg and Stamper (1981) observed significant residues of the malaoxon metabolite under cool dry conditions, whereas it was rarely detectable under hot, wet, humid conditions. DFRs for the carbamate insecticide carbosulfan and its metabolite carbofuran (Nigg, Stamper, and Knaak 1984) and the growth regulator diflubenzuron (Nigg, Cannizzaro, and Stamper 1986) also were observed to be less persistent in Florida citrus groves under hot, wet conditions as compared to cool, dry conditions. It was clear from these studies and a number of others that dissipation curves for pesticide DFRs in citrus were very dependent on a number of postapplication environmental and climatic factors and that realistic reentry intervals would have to vary with different conditions. In response to this, systematic leaf disk sampling and extraction methods were developed to estimate DFRs in citrus, which were in turn related to the toxicity of the particular pesticide, in order to calculate safe reentry intervals (Gunther et al. 1973; Iwata et al. 1977; Knaak 1980). Nigg, Stamper, and Queen (1984) developed a simple regression model for predicting transfer of insecticide DFRs from foliage to the bodies of Florida citrus workers and found close agreement with an earlier California model developed by Popendorf and Leffingwell (1982). They felt that differences in application rates, initial residues, and climate were more than adequate to explain the different dissipation rates of DFRs between the two regions and that perhaps the role of foliar dust in California had been overemphasized.
Non-carcinogenic health risk from carbamate pesticide exposure of toddlers living in agricultural areas of Thailand
Published in International Journal of Environmental Health Research, 2022
Satinee Siriwat, Parichat Ong-Artborirak, Chakrit Ponrachom, Wattasit Siriwong, Thitirat Nganchamung
The hazard quotient (HQ) was used to determine the non-carcinogenic risks of each carbamate pesticide exposure for aldicarb, carbaryl, carbofuran, carbosulfan, and methomyl based on Equation 3.