Criteria atrazine

II. 0 xg/L for salt marsh algae, based on the least effect level of 110.0 Jig/L, and an uncertainty factor of 10. Atrazine concentrations >11.0 xg/L sometimes occur during periods of runoff and non-flushing, but rarely persist at levels necessary to markedly inhibit photosynthesis in aquatic plants, i.e., 60.0-70.0 xg/L. At 80.0 xg/L, rainbow trout show kidney necrosis of endothelial cells after exposure for 28 days, and this suggests that atrazine criteria that protect sensitive plants will also protect aquatic vertebrates. 

In recent studies, pesticides such as atrazine have been found in precipitation. Therefore volatilization and subsequent transport in the gaseous phase is an important environmental pathway. Vaporization rates of pesticides deposited on surface of soil and plant leaves depend on the physical-chemical properties of the substance. A useful physicochemical criterion is Henry s constant, Ku, which is defined as the equilibrium air-to-water partial pressure ratio of the substance (see Chapter 7). 

BW daily for a 60-kg person. Both TRMC estimates are substantially below the proposed limit of 0.0375 mg/kg BW daily. Lifetime exposure to drinking water concentrations of 2.3 (xg atrazine/L poses negligible risk to human health, as judged by the no adverse effect level of 7.5 xg/L when 1% of the allowable daily intake is obtained from this source. Higher allowable concentrations are proposed over short periods 123.0 xg/L for adults and 35.0 jig/L for children, over a 10-day period. The proposed drinking water criterion to protect human health in Western Europe is <0.1 Jig/L. In the United States, it should not exceed 3.0 jig atrazine/L drinking water, although some authorities recommend less than 3.6 jig atrazine/L. 

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