The Standard - October 2021 Share

In July 2021, the United States EPA announced their posting of PCB Method 1628, Polychlorinated Biphenyl (PCB) Congeners in Water, Soil, Sediment, Biosolids, and Tissue by Low-resolution GC/MS using Selected Ion Monitoring, on the Clean Water Act methods web page. Method 1628 was developed to be a new alternative method for wastewater compliance monitoring. Currently the only 40 CFR Part 136 approved method for PCB analysis in wastewater is Method 608.3, which is limited to reporting against 7 Aroclor mixtures, and does not significantly relate to typical patterns of PCBs in weathered samples. Method 1628 can detect all 209 PCB congeners and uses 29 ¹³C-stable isotope labeled PCB congeners to allow for Isotope Dilution MS analysis.  

 

For more details about the method and its purpose please visit: https://www.epa.gov/cwa-methods/pcb-congeners-low-resolution-gc-ms-method-1628-not-yet-approved 

 

But … there is a warning at this time that: “Method 1628 is not yet approved at 40 CFR Part 136 for use in Clean Water Act compliance monitoring. The method would need to be proposed and promulgated in a future rulemaking to become an approved method. However, having completed a multi-laboratory validation study, EPA considers the method suitable for release to laboratories, regulators, regulated industries, and the general public. States authorized to issue NPDES permits may elect to use this method in permits, pending nationwide approval by EPA.” 

 

In 2018 Cambridge Isotope Laboratories, Inc. (CIL) developed analytical calibration and spiking standard mixtures to be used in the new multi-matrix, low-resolution GC/MS PCB method. Our standard mixtures were developed specifically to meet the scope of Method 1628 testing and were provided by CIL to support the 2019 multi-laboratory validation project. These standard mixtures are now available from CIL as follows: 

 

Catalog No.	Description	Amount
EC-5612	EPA Method 1628 Calibration Standard Solutions  [CS1-CS6]	6 x 0.2 mL in nonane/isooctane
EC-5614	EPA Method 1628 Native Standard Solution	5 mL in acetonitrile
EC-5613	EPA Method 1628 Labeled Compound Standard Solution	1.2 mL in acetonitrile
EC-5615	EPA Method 1628 Non-Extracted Internal Standard Solution	1.2 mL in nonane