The following compounds are listed by UNEP to be POPS: • Pesticides: Aldrin, Chlordane, DDT, Dieldrin, Endrin, Heptachlor, Mirex, and Toxaphene • Industrial chemicals: Hexachlorobenzene, and PCB (polychlorinated biphenyl) • Chemical by-products (Dioxins): Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD and PCDF) This application note describes methods and results for extraction of the POPs listed above, with tables comparing ASE to traditional extraction methods.

Polybrominated diphenyl ethers (PBDEs) were developed in the early 1970s and are used as flame retardants for various consumer products, including clothing, furniture, and plastics. Accelerated Solvent Extraction (ASE), introduced in 1995, was EPA approved under method 3545A and has proven to be a valuable technique for environmental laboratories. In this application note, PBDEs were extracted from human breast milk (freeze dried), sediments, fish tissues, and polymers using ASE.

The procedures described in this application note meet the requirements for sample extraction as determined by U. S. EPA Method 3545(A). This method is applicable to the extraction of water-insoluble or slightly water-soluble volatile and semivolatile compounds in preparation for GC/MS measurement. This method is applicable to soils, clays, wastes, and sediments containing from 250–12500 µg/kg of BNA compounds.

The method presented here overcomes analyte interference by separating the two chromium using a detection method specific for Cr(VI) that is capable of handling the high-ionic-strength sample matrices generated in many leaching, and digestion procedures. Cr(VI) is separated as the divalent anion on the IonPac AS7 column using ammonium sulfate, ammonium hydroxide eluent. After the separation, Cr(VI) reacts with the color reagent diphenylcarbohydrazide (DPC) and detected by UV absorbance at 520 nm. This method is consistent with U.S. EPA Method 218.6. Please refer to AU179 for an updated method.

This application update describes the determination of the metal cyanide complexes of iron, cobalt, silver, gold, copper, and nickel in solid wastes by anion-exchange chromatography with UV absorbance detection. Metal cyanide complexes are solubilized and recovered by an alkaline extraction procedure (SW846 Method 9013) prior to chromatographic analysis. Two analytical approaches are available depending on the concentration of metal cyanides expected in the leachate; the two methods differ only in how the sample is injected.