The St-Charles Plain (Kent County, New Brunswick, Canada) commercial peat moss operation has been ongoing since 1983. To process the peat, a dry extraction method is used that requires extensive drainage of the peat bog. The water is directed toward sedimentation ponds, where it drains into a small brook, which feeds into a river affected by tidal salt water. Water discharge from the bog contains large amounts of peat particles that deposit in the surrounding watershed. As a result, the pH of the freshwater sites that receive the drainage water from the commercial operation, is fairly acidic (pH 3.9-4.7). Water samples from or near the peat moss operation have a higher concentration of total phosphorous and total organic carbon. The peat particles contain relatively high levels of total mercury, as reflected by analysis of peat sediments. However, the water samples contained low levels of dissolved mercury. Indigenous samples of biota-namely, sand shrimps (Crangon septemspinosa) and mummichogs (Fundulus heteroclitus)-did not contain mercury levels higher in the impacted sites than in the reference sites. Introduced blue mussels (Mytilus edulis) did not accumulate significant amounts of mercury during a 62-day exposure in the study area. Overall, the data suggest that although relatively large amounts of mercury-containing peat particles are discharged into the ecosystem, bioaccumulation of mercury in the biota does not occur.
This paper describes the results from a pesticide residue survey conducted in relation to the 1980 spraying of insecticides in New Brunswick (Canada) to preserve the coniferous forest from an on-going spruce budworm infestation. A total of 465 water and air samples were collected from 12 sites throughout the Province. In water, fenitrothion was usually detected at about the same time that spraying occurred in the immediate area of the sites. The maximum that was ever detected was 20.0 ppb and persistence was usually limited to a few days except in a small pond where fenitrothion was detected for a total of 18 consecutive days. Aminofenitrothion was also detected at a maximum of 8.0 ppb. Fenitrothion was only detected occasionally in air samples the maximum being 1.2 ng/dm3. However, amino-fenitrothion was present in several air samples at a maximum of 12.0 ng/dm3.
We describe two fully enzymic methods, fluorometric and colorimetric, for determination of triglycerides (triacylglycerols) in serum. Samples are incubated with microbial lipase for 10 min, and the glycerol released from the triglycerides is oxidized by NAD+ in the presence of glycerol dehydrogenase. In the fluorometric method, the resulting NADH is in turn oxidized by resazurin as catalyzed by diaphorase to form resorufin, a highly fluorescent compound. In the colorimetric method, the NADH is oxidized by coupling with a tetrazolium salt/diaphorase system to form formazan, a highly colored compound. Calibration curves, constructed by plotting change in fluorescence or absorbance vs concentration of triglycerides, were linear up to 6 and 5 g of triglycerides per liter of serum for the fluorometric and colorimetric methods, respectively. The assays require only 5 and 15 microL of serum for fluorometry and colorimetry, respectively. The CV was 0.59% for the fluorometric method, 0.91% for the colorimetric procedure. The time for analysis for either method is less than 15 min. The results correlate well with those obtained by the Dow Diagnostic Kit method, a colorimetric method in which glycerol kinase and glycerol-1-phosphate dehydrogenase form NADH from ATP and NAD+ in the presence of glycerol and glycerol 1-phosphate.
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