Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory-Determination of organochlorine pesticides and polychlorinated biphenyls in bottom sediment by dual capillary-column gas chromatography with electron-capture detection

Abstract

A method for the determination of 30 individual organochlorine pesticides, total toxaphene, and total poly chlorinated biphenyls (PCBs) in aquatic bottom sediment is described and laboratory performance data are provided. The method was developed in support of the U.S. Geological Survey's National Water-Quality Assessment program and is based on conventional Soxhlet extraction using dichloromethane. Two aliquots of the sample extract are quantitatively injected onto a styrene-divinylbenzene gel permeation column and eluted with dichloromethane. This gel permeation chromatography step removes inorganic sulfur and large naturally occurring molecules from the sediment extract. The first aliquot is analyzed for semivolatile organic compounds by gas chromatography with mass spectrometric detection. The second aliquot is further split into two fractions by combined alumina/silica adsorption chromatography prior to determination of the organochlorine pesticides and PCBs by dual capillary-column gas chromatography with electron-capture detection (GC/ECD). This report completely describes and is limited to the determination of the organochlorine pesticides and PCBs by GC/ECD. Current (February 1995) data-reporting limits have been set at 1 to 5 micrograms per kilogram for 30 chlorinated pesticides, 50 micrograms per kilogram for total PCBs, and 200 micrograms per kilogram for toxaphene. SAFETY CONSIDERATIONS This method involves the handling of known, suspected, and possibly unknown hazardous chemicals and reagents. The method uses substantial volumes of dichloromethane, a suspected carcinogen, during sample extraction and some extract clean-up steps. The USEPA has special regulations covering the handling and disposal of PCBs. Carefully follow all standard safety practices regarding the use of solvents, compressed gases, OC pesticides, PCBs, polycyclic aromatic hydrocarbons, and other method-related chemicals. Consult material safety data sheets for additional safety information. Always wear appropriate protective clothing, gloves, and eye wear, and use adequate ventilation when preparing samples or standard solutions. Electron-capture detectors (ECDs) contain radioactive 63nickel and must not be opened by unlicensed operators. ANALYTICAL METHOD Organic Compounds and Parameter Codes: Organochlorine pesticides and gross polychlorinated biphenyls, bottom sediment, gas chromatography, O-5129-95 (see table 1)

Predicting the probability of detecting organochlorine pesticides and polychlorinated biphenyls in stream systems on the basis of land use in the Pacific Northwest, USA

“…The minimum detection limits for each compound were determined on the basis of the methods outlined by the U.S. Environmental Protection Agency (U.S. EPA) [29]. Sample preparation and analysis details and minimum reporting level determinations are provided in Foreman et al [30] and Leiker et al [31].…”

“…The minimum detection limits for each compound were determined on the basis of the methods outlined by the U.S. Environmental Protection Agency (U.S. EPA) [29]. Sample preparation and analysis details and minimum reporting level determinations are provided in Foreman et al [30] and Leiker et al [31]. Laboratory quality assurance samples were used to estimate the quality of the analytical data, to determine the need for internal laboratory corrective action, and to interpret results after corrective action procedures were implemented.…”

Polychlorinated biphenyls, mercury, and potential endocrine disruption in fish from the Hudson River, New York, USA

“…Total carbon, organic carbon, inorganic carbon, Aroclors 1242, 1254, and 1260, total PCBs, organochlorine insecticides, polyaromatic hydrocarbons (PAH), and other potential endocrine-disrupting compounds (e.g., 17b-estradiol) were measured in sediment samples following standard extraction, cleanup, and fractionation techniques (Foreman et al, 1995;Furlong et al, 1996). Some procedures were slightly modified by the USGS NWQL to determine estradiol and cholesterol.…”

Regression models for explaining and predicting concentrations of organochlorine pesticides in fish from streams in the United States

“…Bed sediment samples were collected on the same date as fish samples for 49% of sites, within one year for 86% of sites, and within three years for the remainder. Sediment samples were composites of fine‐grained sediment (sieved to <2 mm) collected from multiple depositional areas within a stream reach on a single date, typically during low‐flow conditions ([29]; http://water.usgs.gov/nawqa/pnsp/pubs/ofr94-458), and analyzed for organochlorine pesticides by gas chromatography with electron capture detection ([30]; http://nwql.usgs.gov/OFR-95-140.shtml).…”