PESTICIDES GENETIC EFFECTS

Since all pesticides are mutagenic, there must be long-term genetic effects accompanying their direct and immediate consequences. 

Bignami M, Comba P, lachetta R, et al. 1977. Relation between mutagenic activity and chemical structure in some pesticides Their effects on Aspergillus nidulans. Atti Ass Genet Ital 22 51- 52. 

The genetic effects of organochlorine pesticides have been examined in a number of in, vitro short-term tests (Table III). 

L Vova TS. 1984. [Study of the mutagenic effect of 5 promising pesticides in mouse bone marrow cultured human peripheral blood lymphocytes, and in the yeast Saccharomyces-cerevisiae.] Tsitol Genet 18 455-457. (Russian)... 

As explained in Section 5.2.3, p,p -DDE is much more persistent in food chains than either p,p -DDT or p,p -DDD, and dnring the 1960s when DDT was still extensively used, it was often the most abundant of the three compounds in birds and mammals found or sampled in the field. Since the widespread banning of DDT, very little of the pesticides has been released into the environment, and p,p -DDE is by far the most abnndant DDT residue found in biota. While discussing the ecological effects of DDT and related compounds, effects on population numbers will be considered before those on popnlation genetics (gene frequencies). 

Xenobiotics, for the most part, have limited biological half-lives. The extent of their influence on the biological living system is limited on the basis of the amount absorbed and the duration of their presence within the system. Once exposure to a pesticide chemical occurs, individuals need not be unduly fearful of adverse health impacts slowly and relentlessly progressing regardless of dose and duration of exposure. There are effects such as cancer induction and genetic mutations which have yet to be characterized and fully understood from a chemical standpoint. Consideration of these special conditions has been the subject of entire seminars and obviously cannot be covered fully in a presentation such as this. 

Davis A, Barale R, Brun G, et al. 1987. Evaluation of the genetic and embryotoxic effects of bis(tri-n-butyltin)oxide (TBTO), a broad-spectrum pesticide, in multiple iowivo and iruvitro short-term tests. Mutat Res 188 65-95. 

Since a majority of toxic chemicals trigger multiple adverse effects, it is important to understand the spectrum of effects. Such data on chemical(s) help to evaluate the chemical safety and/or health risks posed to humans. Simultaneous exposure to multiple chemicals makes the problem more complex. All these aspects suggest a plethora of toxic effects of chemical combinations. Further, as seen in the acute toxicity profile of pesticides on bird species, the genetic diversity of animal species and humans underlines the role of individual sensitivities on the induction of toxic effects of chemicals. 

W.W. Au, C.H. Sierra-Torres, N. Cajas-Salazar, B.K. Shipp, M.S. Legator, Cytogenetic effects from exposure to mixed pesticides and the influence from genetic susceptibility. Environ. Health Perspect. 107(6) 501, 1999. 

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