Pesticides acute

TABLE 4-2. Signs and symptoms of insecticide poisoning Chlorinated hydrocarbon pesticides Acute Chronic... 

Pesticide Acute toxicity Sex reversal assay, PLC or VTC induction assay ... 

Acute toxicity testing Guidance for waiving or bridging of mammalian acute toxicity tests for pesticides (acute oral. In vivo... 

Pesticides include the broad categories of insecticides, fungicides, rodenticides, and herbicides. Insecticides in common use fall into three categories. The chloroinsec-ticides have chlorine in their structure. They are less soluble than the other insecticide forms and much less biodegradable (i.e., more persistent). While they are less acutely toxic, several have been identified as potential carcinogens. Carbamatea are a relatively new form of pesticide. They are less persistent and less... 

Toxic to individual species or broadly hazardous Pesticides, fungicides, herbicides, insecticides, fumigants Toxic to humans Chronic or acute... 

Many very hazardous solvents, such as benzene and carbon tetrachloride, were widely used until the 1970s. The situation was very similar for the use of pesticides. Among the toxic pesticides that were still in wide use 20 years ago were chlorophenols, DDT, lindane, and arsenic salts, all of which are classified as human carcinogens as well as being acutely toxic. Fortunately, use of these kinds of very toxic chemicals is now limited in the industrialized world. However, because the number of chemicals used in various industries continues to increase, the risks of long-term health hazards due to long-term exposure to low concentrations of chemicals continues to be a problem in the workplace. 

The lymphocytes from 31 patients exposed to various organophosphate pesticides were examined for chromosomal aberrations (Van Bao et al. 1974). Five of the patients were exposed to methyl parathion only. Blood samples were taken 3-6 days after exposure and again at 30 and 180 days. A significant (p<0.05) increase was noted in the frequency of stable chromosomal aberrations in acutely intoxicated persons (although such cells are eventually lost from the cell population). Two of the methyl parathion-exposed persons had taken large doses orally in suicide attempts. The study limitations include small sample size, absence of a control group, lack of quantification of exposure levels, and possible... 

For methyl parathion, most of the information on health effects in humans is derived from cases of acute exposure to relatively high concentrations of the pesticide. Such reports have not addressed the issue of the potential endocrine-disrupting capacity of methyl parathion in humans. An added complication in determining whether methyl parathion has endocrine-disrupting capabilities in humans is the fact that humans are seldom exposed to a single pesticide. 

Azaroff LS, Neas LM. 1999. Acute health effects associated with nonoccupational pesticide exposure in mral El Salvador. Environ Res A80 158-164. 

EPA 1978e. Teratology and acute toxicity of selected chemical pesticides administered by inhalation. Research Triangle Park, NC U.S. Environmental Protection Agency, Office of Research and Development, Health Effects Research Laboratory. EPA-600/1-78-003 NTIS PB-277 077. 

Gaines TB. 1960. The acute toxicity of pesticides to rats. Toxicol Appl Pharmacol 2 88-99. 

Gaines TB. 1969. Acute toxicity of pesticides. Toxicol Appl Pharmacol 4 515-534. 

Golbs S, Fuchs V, Leipner E, et al. 1978a. [Studies into effects of pesticide combinations on laboratory rats. 1st communication Determination of the acute oral toxicity (ED50) of pesticide combinations]. Arch Exp Vet Med Leipzig 32 557-561. (German)... 

Isshiki K, Miyata K, Martsui S, et al. 1983. [Effects of post-harvest fungicides and piperonyl butoxide on the acute toxicity of pesticides in mice. Safety evaluation for intake of food additives. III]. 

Sultatos LG. 1987. The role of the liver in mediating the acute toxicity of the pesticide methyl parathion in the mouse. Drug Metab Disp 15 613-617. 

Most of the hterature reviewed concerning the health effects of endosulfan in humans described case reports of occupational exposure and accidental or intentional ingestion of endosulfan. The cases of occupational exposure to endosulfan concerned exposures of acute-to-intermediate durations, and the cases of oral exposure were exclusively acute-duration exposure situations. The predominant route of exposure in the occupational case reports is believed to be inhalation, but the possibility of some degree of dermal exposure cannot be ruled out. The information on human exposure is limited because the possibility of concurrent exposure to other pesticides or other toxic substances cannot be excluded. In addition, the precise duration and level of exposure to endosulfan generally cannot be quantified from the information presented in these reports. 

In terms of toxicity, NIOSH recommends that endosulfan be recognized as a Group 1 Pesticide (NIOSH 1992). Pesticides in Group 1 pose a significant risk of adverse acute health effects at low concentrations or carcinogenic, teratogenic, neurotoxic, or reproductive effects (NIOSH 1992). 

Edson, E.F., Sanderson, D.M., and Noakes, D.N. (1966). Acute toxicity data for pesticides. World Review of Pest Control 5 (3) Autumn, 143-151. 

Devillers J. A general QSAR model for predicting the acute toxicity of pesticides to Lepomis macrochirus. SAR QSAR Environ Res 2001 11 397-417. 

In many cases, there is difficulty in preserving residues in samples after collection and prior to pesticide analysis which coincides with a rapid further degradation and mineralization of the pesticide residues under most environmental conditions. Storage stability studies and studies on the reactivity of sample collection equipment in addition to field quality assurance procedures can help address some of these questions. Concerns are accentuated for compounds that have short half-lives in the environment but still have high acute toxicity. 

---