Urinalysis of atrazine exposure in farm pesticide applicators.

This study compared three relatively common laboratory methods for the detection of atrazine (a triazine herbicide commonly used in US agriculture), and related metabolites in urine. Ninety-nine samples collected from atrazine applicators within 8 h post application were analyzed. Thirty-seven percent of applicators showed detectable levels (minimum = 1.0 ng/ml) of deethylatrazine (an atrazine metabolite typically found in environmental samples) in their urine, based on gas chromatography-mass spectrometry (GC-MS) analysis (mean = 14.2 ng/ml). Fifty applicator samples were tested using an enzyme-linked immunosorbent assay (ELISA) designed for the mercapturate metabolic product. Most of these samples (80%) had detectable levels of the mercapturate product. A triazine in water ELISA was also used to test several diluted urine samples from atrazine applicators, and all samples were positive for triazines. Mediocre agreements between the three methods indicated that each detected distinct atrazine exposure products. The results indicate that single field applications of atrazine result in measurable pesticide doses to applicators and that the choice of field assay should depend on the exposure product to be evaluated.

Monitoring in the Tualatin River Basin to assess the effectiveness of the Oregon Forest Practicers Program: Preliminary results of phosphorus monitoring.

The Oregon Department of Forestry is a designated management agency to provide a forestry program to assist in bringing the Tualatin River into complicance with pH and dissolved oxygen water quality standards. The Oregon Environmental Quality Commission set a total maximum daily load (TMDL) of 70 µg/l total phosphorus to control algae growth and meet these standards. The Department of Forestry has a basin effectiveness monitoring plan to determine that the Oregon Forest Practice Rules' BMPs are maintaining adequate control of phosphorus loadings from forest operations. Three sites monitored during May to October of 1990 were augmented by eight more sites in 1991. As laboratory methods were refined, the results became more accurate. The 1991 monitoring showed lower phosphorus levels that were consistent for each tributary. Mean total phosphorus levels ranged from 17 to 65 µg/l. Preliminary field reconnaissance suggests a correlation between phosphorus levels and underlying geology. Concentrations were lowest at sites underlain by tertiary intrusive basalts, next higher for sites with terrestrial basalt, next higher for one site with a basalt-sandstone bedrock mix, and highest for sites underlain predominately by sandstone. These results may be modified by 1992 monitoring and further analysis.

Polychlorinated biphenyl congeners in blood of Wisconsin sport fish consumers.

As part of a study to evaluate the effect of chemical contaminants on Wisconsin sport fish consumers, measurements were made of polychlorinated biphenyl (PCB) congeners in human blood sera. A high resolution gas chromatography procedure was employed, with 13 individual congeners used as standards. Analytical recoveries and precision were greater than 90% and replicates were always within +/- 30%. Total concentrations, obtained by summing quantified congeners, ranged from 0.6 to 27.1 micrograms/L. Conventional packed column PCB analysis, conducted on a subset of samples, gave higher total PCB results. On a congener specific basis, congeners 153 (245-245), 138 (234-245), 180 (2345-245) and 118 (245-34) were found most often. These congeners have been reported to be prominent in other matrices. Of the congeners found, 118, 138, and possibly 180 are potentially the most toxic (based on current toxicological information).