Residues in drinking water

The emphasis that the FQPA placed on the assessment of pesticide residues in drinking water, for example, led to the collection and analysis of data on the effects of drinking water treatment processes on pesticide residues. These data were presented to the FIFRA Science Advisory Board to highlight the variability in the effects of treatment on different kinds of pesticides and the products formed and the variability of treatment processes employed at different locations and at different collection time intervals at an individual location. These complexities led to the current proposal... 

In the USA, the passage of the Food Quality Protection Act (FQPA) of 1996 has had a significant impact on the determination of residues in drinking water. FQPA requires that all sources of a pesticide be included in its risk assessment, so the potential exposure from drinking water containing a particular pesticide could be a significant... 

Visweswariah, K., Jayaram, M., Venkataramaiah, G. H., Investigations on BHC residues in drinking water from coffee plantations and coffee beans, J. Coffee Res., 3, 96, 1973. (CA84 146057e)... 

Griese MH, Kaczur JJ, Gordon G. 1992. Combining methods for the reduction of oxychlorine residuals in drinking water. J Am Water Works Assoc 84(11) 69-77. 

Ang, C., Meleady, K., Wallace L. (1989) Pesticide residues in drinking water in the north coast region of New South Wales, Australia. Bull. Environ. Contam. Toxicol. 42, 595-602. 

The use of weedkillers has also been on the increase over the last 20 to 30 years. Although it is difficult to prove specifically which chemicals may be carcinogenic, there are increased levels of herbicidal residues in drinking water and concerns over many of the synthetic substances being used. Every year, governments in various countries withdraw from use chemicals that have previously been used on our food supply when proof of their toxicity is established. The classic example is DDT, which was used as an insecticide from 1939. Over a period of 50 years almost five billion pounds of it have been used across the world. It became prohibited in the US in the 1970s and in the UK in 1984 because of links to deaths, cancer, allergies, infertility, problems in fetal development and major diseases of the immune system. 

EPA s emergency suspension forced states with EDB-contaminated wells to scramble for an EDB drinking water action level. EPA advised Hawaii that EDB residues in drinking water above the detection level of 20 ppt should be considered unsafe. EPA s Scientific Advisory Panel (SAP) has concurred with this decision. 

Wang and Yuan [13] applied leucomethylene blue reagent for the determination of chlorine dioxide disinfectant residues in drinking water and wastewater samples. In their method, the sample is mixed with 3 cm reagent solution (20 mg/dm ), filled up to 20 cm, and extracted with 1,2-dichloroethane at pH 1.3. After a reaction time of 10 min the absorbance is measured at 658 nm. The interfering chlorine and h5q30chlorite ions can be masked by adding oxalic acid. 

Seccia, S. et al.. Multiresidue determination of nicotinoid insecticide residues in drinking water by liquid chromatography with electrospray ionization mass spectrometry. Anal. Chim. Acta, 553, 21, 2005. 

The perception of triazines as safe compounds was modified when a chronic study conducted in the mid-1980s showed effects of atrazine on mammary tumors in rats (WHO 1990). As a result, manufacturers introduced restricted personnel exposure levels. The discovery that atrazine was often present where pesticide residues in drinking water exceeded the newly defined European limit of 0.1 /ig/h for any active ingredient, and subsequent media reports and public discussions that made no distinction between detection and hazard, promoted a feeling of insecurity toward the formerly unchallenged products. The development reached a level of misinformation such that atrazine was occasionally chosen as an instrument to attempt suicide (Section III). A virtually unlimited level of tolerance was fortunately experienced in these unfortunate attempts. 

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