Atrazine monitoring data

The CWS with atrazine and simazine monitoring data served populations of 182 and 183 million, respectively (Tables 29.3 and 29.4). The populations associated with atrazine monitoring data represent 85% of community systems and 78% of total populations, respectively, in the 32 states (Table 29.3). The populations assessed for simazine exposure were 86% and 78% of the assessed water systems and total population, respectively (Table 29.4). 

Until recently, the NRA has not participated during the approval process in assessing the potential environmental impact of pesticides. However, the NRA does supply monitoring data to MAFF and HSE for pesticide reviews. These occur once a pesticide has been approved for use for a certain length of time, or when further information is needed on an approved pesticide. In supplying these data, the NRA comments on any areas of concern. This contributed to the 1993 ban on the use of atrazine and simazine on non-cropped land. In January 1995 the NRA s National Centre for Toxic and Persistent Substances (TAPS) was made advisor to the DoF, on the potential impact on the aquatic environment of... 

Atrazine and Simazine Monitoring Data in Community Water Systems in the United States during 1993 to 2000... 

There are 41362 CWS in these 32 states, serving a population of 213 million. Sixty-eight percent of the systems (28280) had monitoring data for atrazine. Sixty-eight percent (27959) had data for simazine. Eighty-five percent (182 million) of the population was assessed for atrazine and 86% (183 million) for simazine. The assessed populations in these 32 states represent 78% of the US population. 

There are 41362 community systems in the 32 major-use states. These facilities provide drinking water to 91% (213 million) of the 234 million people in these states (Table 29.2). SDWA quarterly compliance-monitoring data for atrazine and simazine from community systems in the 32 major-use states were obtained from the state regulatory agencies. These primary data represent an 8-year period (January 1993 to December 2000). There are 28280 CWS (68%) with 146683 samples analyzed for atrazine in the PLEX database (Table 29.3) and 27959 community systems (68%) with 137 956 simazine data points (Table 29.4). 

The exposure of populations served by CWS to atrazine and simazine in each of the 32 states was evaluated using SDWA compliance monitoring data collected between January 1993 and December 2000 (Tables 29.3 and 29.4). These data represented the best available information from state SDWA agencies in the 32 states. Drinking water data entered into the PLEX database provided a direct link between the population and the estimated concentration of atrazine and simazine in the drinking water. 

More recent water monitoring data. (Data used in this assessment were collected prior to June 1994, and atrazine levels in water are declining.)... 

To explore the risk implications of mixtures of pesticides and their transformation products occurring in aquatic systems, we have taken data from a recent monitoring study of pesticides and transformation products in US streams [45]. This study looked at the occurrence of the parent compounds alachlor, metolachlor, acetochlor, dimethamid and atrazine as well as transformation products associated with each of these parent compounds. The monitoring was done in the spring and autumn at a number of sites. 

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