The national occurrence of 83 pesticide compounds in groundwater of the United States and decadal-scale changes in concentrations for 35 compounds were assessed for the 20-year period from 1993-2011. Samples were collected from 1271 wells in 58 nationally distributed well networks. Networks consisted of shallow (mostly monitoring) wells in agricultural and urban land-use areas and deeper (mostl...

In the period 2003 to 2005, a study was conducted to determine the occurrence, and spatial and temporal distribution of 78 pesticides in surface waters of the Lower Fraser Valley (LFV) region of British Columbia, Canada. A high resolution gas chromatography/electron impact high resolution mass spectrometry (HRGC/[EI]HRMS) method capable of detecting analytes at the subnanograms per liter level ...

The adsorption of three s-triazines (atrazine, terbutylazine, and simazine) on three different humic acids (HAs), before and after acidic hydrolysis, was studied at four diverse pH values from 3 to 4.5. The Freundlich sorption affinity (K(f)) and intensity (1/n) of s-triazines were related to the chemical and structural composition of HA and used in a multivariate statistical analysis. At low p...

The aim of the present work was to determine the concentration levels, as well as accumulation and magnification coefficients, of triazine derivatives in herring gulls and Baltic grey seals 11 years after a ban on their use in the EU and eight after their exclusion in Poland. Dead birds were collected in the coastal zone of the Gulf of Gdansk in the years 2010-2012. The grey seals, on the other...

Coupled with off-line extraction, a pre-column derivatization liquid chromatographic fluorescence detection (LC-FL) procedure was developed for the determination of atrazine and simazine in soil, crop and water samples. Concentrations in real samples were expected to be at or below the low ng/g level, which requires pre-concentration of analytes and improved detection. 4-(2-Phthalimidyl) benzoy...