Simazine groundwater contamination

Groundwater contamination by agrochemicals from non-point sources has been well documented in a number of countries [26-28, 30-32], The pesticides that have been detected in regional council groundwater surveys include 2,4-D, Amitrole, Picloram, Simazine and Atrazine [20]. 

Guideline values proposed by the World Health Organization based on a toxicological approach for each substance are 2 /rg/l for simazine and atrazine, and 20 /rg/l for alachlor. Directive 91/414/CE harmonizes at the European scale the principle of authorization delivery of active substances. For example, a herbicide can be introduced in the positive list of the directive Annex 1 if only the scenario takes into account toxicity, ecotoxicity, and study on presence and fate in the environment, in order to exclude aU risks of groundwater contamination at levels higher than... 

In several AT studies, pesticide levels in the Ebro were found to be high. Hildebrandt et al. [50] found a homogeneous contamination pattern from atrazine (and also from simazine from May 2000) in intensive Rioja cultivation areas throughout the Ebro. Nearer to the delta, Barata et al. [72] found high levels of bentazone, methyl-4-chlorophenoxyacetic acid, propanil, molinate and fenitrothion in water, while Kuster et al. [71] found low concentration levels of atrazine and simazine at the delta, but high levels of other pesticides used in rice cultivation. Importantly, Hildebrandt et al. [50] found that levels of pesticides in groundwater... 

Zalkin, F. Wilkerson, M. Oshima, R. J. Pesticide Movement to Groundwater. Vol. II. Pesticide Contamination in the Soil Profile at DBCP, EDB, Simazine and Carbofuran Application Sites" Calif. Dept. Food and Agric. Sacramento, Calif. Final Rep., EPA Grant E009155-79 1984. 

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