Mutagenicity atrazine

This example illustrates the difficulty of showing pesticides mutagenic activity. For example, mutagenic activity was clearly expressed not in the sym-triazine herbicides atrazine and cyanazine, but in their transformation products formed in corn husks ... 

Atrazine was not mutagenic in bacteria and did not cause chromosomal aberrations in cultured rodent cells it did induce DNA strand breaks in stomach, liver, and kidney cells of rats treated orally. ... 

All of the triazines were found to be negative in the specific tests listed in Table 25.5. The overall mutagenic potential of atrazine, simazine, and cyanazine has been reviewed (Brusick, 1994 Hauswirth and Wetzel, 1998 Bogdanffy et al, 2000 USEPA, 2003a), and the weight of the evidence indicates that they are not mutagenic. Cyanazine showed only limited evidence of mutagenicity (USEPA, 1994). 

In addition to plant activation of promutagens, such as dimethyInitrosamine,16 that are also activated in mammalian metabolism, the possibility of unique abilities of plants to activate some substances warrants attention. For example, interest in metabolism of promutagens by plants was stimulated by the evidence11 0 354 that maize can activate the nonmutagenic herbicide atrazine and some related compounds to substances that cure detectable as mutagens in microbial tests. Atrazine was also mutagenic in the waxy locus test in the maize plants themselves.354... 

The environmental implication of the results with atrazine is that application of herbicides, which are widely used in corn agriculture, can lead to mutagenic plant metabolites in crops. More generally, this result suggested that, like mammalian metabolism of promutagens,... 

Based on evidence derived from a large array of assays such as bacterial reverse mutation test, mammalian bone marrow chromosome aberration test, dominant lethal assay, and UDS assay, atrazine was concluded to lack mutagenic potential. 

Liquid cultures of mutagenized algal cells (250 ml, 2.8 x 105 cells/ml) in BS were treated with 15 gM each of DCMU and atrazine, and the flasks were placed in anaerobic jars. The gas phase contained 16.5% H2, 2% C02, 5-20% 02, balanced with Ar. The cultures were grown for a couple of weeks with stirring and illuminated with fluorescent light (70 gE-m 2-s ). At the end of the selection period, the cells were washed with BS medium and revived in liquid BS medium plus 10 mM sodium acetate. 

Data are lacking for atrazine s effects on mammalian wildlife, although there is a growing body of evidence on domestic and small laboratory mammals. Available data demonstrate that mammals are comparatively resistant to atrazine, and that the compoimd is not carcinogenic, mutagenic, or teratogeific. However, there is a reported increase in the... 

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