This study identifies combinations of over 60 pesticides and 8 common disinfectants (or
conditions) including free chlorine, monochloramine, chlorine dioxide, permanganate, ozone,
hydrogen peroxide, photo-oxidation with UV at 254 nm, and hydrolysis at pH 2, pH 7, and pH
12, that exhibit the potential for pesticide degradate formation. Initial parent pesticide
concentrations were less than 25 µg/L, and treatment dosages were on the order of typical
exposures used during water treatment. The reaction media was buffered Milli-Q water adjusted
to pH 6.6 and 8.6. The reactivity of pesticide/oxidant pairs were categorized as "highly reactive"
(>50% parent removal), "moderately reactive" (20-50% parent removal), and "slightly reactive"
(<20% parent removal). The screening study results indicate the most reactive combinations of
transformation agents and pesticides leading to degradates formation in water utilities. Based
upon exposure (e.g., occurrence, usage), reactivity, toxicity and other criteria, several of the most
important systems were studied in detail. The identity and pathway of the major metabolites
were determined using Ion Trap LC/MS, GC/MS, and other techniques. The data presented
helps identify situations of potentially harmful pesticide degradate formation in common
drinking water treatment systems. Includes 19 references, table.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 150 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 8 |
| Published : | 11/01/2007 |
