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Polybrominated Diphenyl Ethers by LVI-GC/MS-SIM

April 4th, 2004

Polybrominated Diphenyl Ethers by LVI-GC/MS-SIMColumbia Analytical Services, Inc. (CAS) now offers the analysis of Polybrominated Diphenyl Ethers (PBDEs), a class of brominated flameretardants that have been used over the past 30 years in textiles, high impact plastics and electronic circuitry. Recently, they have gained increased attention as “emergent chemicals” because of their persistence in the environment, potential for bioaccumulation, and toxicity. PBDEs are similar in structure to PCB’s, dioxins and furans.

The target compound list developed at CAS is based on the most environmentally significant and lipophilic congeners. The list is derived from the primary components of the major technical products currently in use. Table 1 lists the target compounds along with the achievable method reporting limit (MRL) and method detection limit (MDL).

The sample preparation for soils, sediments and tissues is based on EPA Method 3541, an automated soxhlet procedure. An optimal sample size of 20 grams is extracted for soil and sediments while 10 grams are extracted for tissues. Tissues may also be freeze-dried prior to extraction. The extraction of waters uses a one liter sample volume and is performed in accordance with EPA Method 3520, continuous liquid-liquid extraction. Improved selectivity for the target analytes is achieved by performing silica gel and acid cleanups. These sample preparation techniques have been validated and are routinely employed at CAS.

The analytical portion of the PBDE determination is performed by EPA Method 8270C using high-resolution gas chromatography and mass spectroscopy (HRGC/MS). Sensitivity for the target compounds was improved through the use of an ATAS Optic Large Volume Injector (LVI) that allows a 20ul injection into the gas chromatograph. After the residual solvent is evaporated, a large pressure pulse is applied while the port is rapidly heated to transfer the analyte. This is a splitless injection technique that allows for a greater mass of the target analyte to be transferred to the GC column. The Mass Spectroscopy detector is an Agilent “inert” ion source and the data is acquired in the selected ion-monitoring (SIM) mode, resulting in improved sensitivity. A primary and two confirmation ions are acquired for quantitation of the target compounds.

Columbia Analytical Services, Inc. (CAS) now offers the analysis of Polybrominated Diphenyl Ethers (PBDEs), a class of brominated flameretardants that have been used over the past 30 years in textiles, high impact plastics and electronic circuitry. Recently, they have gained increased attention as “emergent chemicals” because of their persistence in the environment, potential for bioaccumulation, and toxicity. PBDEs are similar in structure to PCB’s, dioxins and furans.

The addition of this method to our capabilities is indicative of our commitment to technical innovation and providing our clients with unsurpassed technical excellence.

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