What is Other Test Method 45 (OTM-45)? What is PFAS?

Measurement of Selected Per- and Polyfluorinated Alkyl Substances from Stationary Sources

This method identifies and determines the concentration in mass per unit gas volume sampled of
specific PFAS compounds in source emissions. Gaseous and particulate bound target pollutants
are withdrawn from the gas stream isokinetically and collected in the sample probe, on a glass
fiber or quartz filter, on a packed column of adsorbent material and in a series of impingers. The
target compounds are extracted from the individual sample collection media. The OTM-45 train
results in four (4) discreet sample extract fractions for analysis. The extracts are analyzed by LCMS/MS in the MRM detection mode. Quantification of each analyte is calculated using the
isotope dilution technique. For QC purposes, the percent recoveries of the pre-extraction
standards are calculated using the integrated peak areas of pre-analysis standard(s), which are
added to the final extract and function as traditional internal standards, exclusively applied to the
pre-extraction standards. The use of pre-sampling standards added to XAD-2 collection media
prior to sampling and analyzed in the same manner as targeted PFAS compounds serves as an
indication of the method’s quantitative capture efficiency. This method is not intended to
differentiate between target compounds in particle or vapor fractions. This method uses
isotopically labeled standards to improve method accuracy and precision.

For more information and documents about OTM-45, please consult the EMC Other Test Methods directory.

On March 16, 2022, the U.S. Environmental Protection Agency (EPA) announced two important actions to safeguard communities from products containing Per- and Polyfluoroalkyl Substances (PFAS).

First, as part of EPA’s effort to identify, understand and address PFAS contamination leaching from fluorinated containers, the agency is notifying companies of their obligation to comply with existing requirements under the Toxics Substances Control Act (TSCA) to ensure unintentional PFAS contamination does not occur.
The agency will also remove two PFAS from its Safer Chemical Ingredients List (SCIL) following a review of these substances (which were added to that list in 2012).

“Today’s action will help ensure that responsible parties are held accountable for any future PFAS contamination affecting communities,” said Assistant Administrator for the Office of Chemical Safety and Pollution Prevention Michal Freedhoff. “Additionally, keeping PFAS out of consumer products certified under the agency’s Safer Choice program will help prevent potential exposures to PFAS from occurring in the first place.”