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Posts Tagged ‘EPA method 8081’

Organochlorine Pesticide Analysis using HRGC/MS/MS

Tuesday, March 3rd, 2009

 

Organochlorine pesticides (OCPs) have a long history of use in the United States and around the world. Although the production and use of many OCPs has been banned since the 1970s, the compounds are extremely persistent in the environment and are known for accumulating in sediments, plants and animals. OCPs have a wide range of both acute and chronic health effects, including cancer, neurological damage, and birth defects. Many OCPs are also suspected as endocrine disruptors.1

Due to the need to monitor levels of OCPs, significant research and development has taken place over the last 40 years. This has culminated in two primary methods used by the Environmental Protection Agency (EPA) to regulate the transport and fate of OCPs; EPA Method 1699 and EPA Method 8081.

EPA Method 1699, isotope dilution and high-resolution mass spectrometry, is considered the ultimate in pesticide analysis relative to sensitivity and selectivity, but can be cost prohibitive.

EPA Method 8081 is a gas chromatography method that employs electron capture as a means of detection. To achieve some level of selectivity, the method is run in dual column mode with two dissimilar analytical columns. It has been well documented that the use of ECD can lead to false positives or high biases in the results generated by this method.2

 

This lack of selectivity is especially apparent when polychlorinated biphenyls (PCB) are present in the sample.

 
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Ultra-Low Analysis of Pesticides and PCB Aroclors in Ground Water

Wednesday, February 4th, 2004

Ultra-Low-Analysis-of-Pesticides-and-PCB-Aroclors-in-Ground-WaterThe toxicity and environmental impact of organochlorine pesticides and polychlorinated biphenyls (PCBs) is well documented. Routine environmental analysis of these compounds has remained largely unchanged since the advent of EPA method 8081 and EPA method 8082. However, recent instrumental advances and implementation of ultra-trace extraction techniques have allowed for significant improvements in detection limits.

The CAS Kelso laboratory has developed procedures that produce detection limits low enough to meet the requirements of the majority of studies. The extraction and analysis procedures include modifications to increase sensitivity, but still meet the requirements of the traditional EPA SW846 methods. Samples are prepared according to EPA Method 3520C with modifications, including a 2L continuous liquid-liquid extractor. Special glassware handling techniques are incorporated to minimize potential background contamination.

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