Documents fungicides 14 results

"The aim of this study was to investigate the possibility of subtoxic exposure to pesticides causing chromosome aberrations in greenhouse workers.In a cross-sectional and prospective study design chromosome aberration frequencies in cultured lymphocytes were examined for 116 greenhouse workers exposed to a complex mixture of almost 50 insecticides, fungicides, and growth regulators and also for 29 nonsmoking, nonpesticide-exposed referents.The preseason frequencies of chromosome aberrations were slightly but not statistically significantly elevated for the greenhouse workers when they were compared with the referents. After a summer season of pesticide spraying in the greenhouses, the total frequencies of cells with chromosome aberrations were significantly higher than in the preseason samples (P=0.02) and also higher than for the referents (P=0.05). This finding was especially due to an increased number of cells with chromatid gaps between the first and second samples (P=0.001). The results may reflect an additive genotoxic effect of the spraying season, for which the use of insecticides and growth regulators (but not fungicides) culminates. The highest elevation in the risk of chromatid gaps was observed for persons who did not use gloves during re-entry activities such as nipping, cutting, pricking, and potting (risk ratio 2.88, 95% confidence interval 1.63-5.11). The present results suggest a genotoxic effect from a complex subtoxic occupational pesticide exposure. In general, the findings indicate the importance of personal protection, during high-exposure re-entry activities, in preventing pesticide uptake and genetic damage. ... "

"Evaluates the risks to human health and the environment posed by benomyl, a fungicide registered for use in 50 countries on over 70 crops, including cereals, cotton, soybeans, tobacco, mushrooms, grapes, bananas and other fruits. One of the most widely used members of the benzimidazole family of fungicides, benomyl is effective, at low usage rates, against more than 190 different fungal diseases. Because benomyl is rapidly converted to carbendazim in the environment and is extensively metabolized to carbendazim by experimental animals, data from studies of carbendazim, which is a fungicide in its own right, are also considered when evaluating the hazards of benomyl.
Concerning hazards to environmental organisms, the report cites data from laboratory and field studies indicating that benomyl, applied at recommended rates, has little effect on soil microbial activity, but some adverse effects on groups of fungi. Benomyl is toxic to earthworms in laboratory experiments at realistic exposure concentrations and as a result of recommended usage in the field; earthworm populations may take more than two years to recover. Although high toxicity to aquatic organisms has been demonstrated in laboratory tests, the report concludes that this effect is unlikely to be seen in the field, due to the low bioavailability of sediment-bound residues.
For the general population, the main source of potential exposure is noted to be through the ingestion of food crops containing residues of benomyl and carbendazim. Though benomyl has been shown to cause contact dermatitis and dermal sensitization in some farm workers, the report found no evidence that either of these compounds can cause systemic toxic effects in occupationally exposed subjects or the general population. The report cites findings from animal studies suggesting that both compounds pose a very low risk for acute poisoning in humans."

Evaluates the risks to human health and the environment posed by exposure to benzene, a naturally occurring chemical found in crude petroleum and manufactured in extremely large quantities worldwide. The presence of benzene in gasoline and in cigarette smoke, combined with its widespread use as an industrial solvent, has resulted in the presence of this chemical in the environment. Because benzene is a well-established human carcinogen, the book gives particular attention to data relating patterns, levels, and duration of exposure to health hazards in both the general population and exposed workers.

A section on sources of exposure identifies emissions from motor vehicles as the largest source of this chemical detected in the general environment. For indoor environments, data show that cigarette smoke results in the exposure of non-smokers as well as smokers to important levels of benzene. The report concludes that most humans are exposed to trace levels, with much higher levels seen in cigarette smokers, those exposed to sidestream smoke, residents in areas of heavy automobile traffic, and workers involved in the production, handling, and use of benzene and its derivatives.

The most extensive section reviews the large number of toxicity studies of benzene. Particular attention is given to the numerous animal studies demonstrating carcinogenicity and exploring the mechanisms by which benzene damages bone marrow and exerts its other toxic effects. The remaining sections assess the risks to human health posed by benzene in both the general population and in exposed workers, giving particular attention to the numerous epidemiological and case studies that have established benzene as a human leukaemogen. Because the health risk of low-level benzene exposure is not yet clearly established, the report concludes that exposure should be avoided as much as possible.