The state of the science of analytical methods for cVOCs

Abstract

As part of its drinking water strategy, the US Environmental Protection Agency (USEPA) attempts to streamline the cost of compliance by regulating contaminants as groups with similar health effects, co‐occurrence, common analytical method(s), and common treatment or control processes. When the announcement to regulate up to 16 carcinogenic volatile organic compounds (cVOCs) as a group included compounds not currently listed in the USEPA analytical methods most commonly used for VOC analysis (methods 524.2 and 524.3), a review of the state of the science of analytical methods was performed. Findings indicated that USEPA method 524.3 can support lower‐level detection of currently regulated VOCs as well as some additional VOCs included in the cVOC group, but a modified sample preservation protocol for (method 524.3) and additional methods (liquid chromatography/mass spectrometry and method 526) will be needed to detect all compounds in the proposed cVOC group at meaningful levels. The number of analytical methods required for the cVOC group will significantly affect the feasibility and analytical cost of compliance monitoring for the cVOC rule if the list remains as proposed.

Evaluation of Effects of Potential Group cVOC Regulations on Two Utilities

“…The minimum reporting level (MRL) for these methods is 0.5 µg/L. Advances in laboratory instrumentation and procedures are lowering the lowest concentration MRL and minimum detection limits for cVOCs to <0.1 µg/L (Eaton et al 2012), which is why the AWWA cVOC Workgroup developed scenario 3 to include individual MCLs of 0.1 µg/L for TCE and PCE. Therefore, it is possible that some cVOCs may be present at levels below the MRL in the historical data but that are at concentrations still relevant to potential regulatory scenarios.…”

Is Regulating By Groups More Effective? Or Not?

“…All of the currently regulated VOCs can be analyzed by one analytical method (USEPA method 524.3). In contrast, on the basis of the initial list of 16 cVOCs, researchers found that a modified sample preservation step under USEPA method 524.2 or 524.3 would be needed, and additional methods (liquid chromatography/mass spectrometry and USEPA method 526) would be needed to detect all of the compounds in the proposed cVOC group at meaningful levels (Eaton et al, 2012). The number of analytical methods required for the cVOC group would significantly affect the feasibility and analytical cost of compliance monitoring for the cVOC rule.…”

Delays in the Regulatory Schedule From Budgets and Others

“…One immediate downside to making any positive regulatory determination is the start of the “regulatory clock”—i.e., USEPA then has 24 months to publish a proposal as required by Section 1412(b)(1)(E) of the Safe Drinking Water Act (SDWA). And nitrosamines have their own set of complicated regulatory issues, such as a relatively small contribution from drinking water to the total risk, which I have written about previously (Roberson, 2012).…”

“…The cVOC Rule is turning out to be USEPA's first test in regulating by groups, and it's turned out to not be as simple as originally anticipated (Roberson, 2013). Previous research found several differences in physical and chemical characteristics for the cVOCs initially considered for this rule as well as the need for multiple analytical methods (Roth, 2012; Eaton, 2012).…”