Posted on May 21, 2019 by Kathy Beckett
In 2015, EPA published its final updated ambient water quality criteria for the protection of human health for 94 chemical pollutants. This updated suite of recommendations was designed to reflect the latest scientific information and EPA policies, including updated body weight, drinking water consumption rate, fish consumption rate (“FCR”), bioaccumulation factors, health toxicity values, and relative source contributions. Presently states and tribes are engaged in the triennial review process for the adoption of the new EPA recommended criteria. As a result of the myriad of factors that comprise the calculation for the new recommended human health criteria, states and tribes are engaged in assessment of the particulars. Stated simply: AWQC (ug/l) = toxicity value (mg/kg-d) x BW (kg) x 1,000 (ug/mg)b divided by [DI (L/d) – Ʃ4 i=2 (FCRi(kg/d) x BAFi(L/kg))].
One notable effort to manage EPA’s fish consumption-based recommendations is found within the Idaho water quality standards setting continuum. In 2012, EPA disapproved Idaho’s assumptions asserting that it failed to demonstrate that the criteria protected Idaho’s designated uses. Specifically, EPA concluded that Idaho failed to consider available local and regional fish consumption information suggesting that fish consumption among some Idaho population groups was greater than 17.5 g/day. EPA’s review of available information suggested that recreational anglers and subsistence fishers in Idaho consume fish at rates higher than the national default rate. In addition, during tribal consultation EPA heard from several tribes that rely on fish and other resources in Idaho waters for subsistence purposes. In its disapproval action, EPA recommended that Idaho further evaluate levels of fish intake by recreational and subsistence fishers in Idaho when evaluating the appropriate FCR for use in deriving criteria. In 2017, EPA informed Idaho that it had not adequately taken into consideration subsistence fishing use by Idaho tribes, and therefore Idaho’s criteria were not sufficiently protective. To make a long technical story short, after committed efforts by Idaho, EPA finally approved the state’s new and revised human health criteria, in April, 2019.
Other states and tribes are moving cautiously relative to these new human health criteria, learning from Idaho that national default assumptions embedded in EPA’s formula will require careful study. EPA developed chemical specific science documents for each of the 94 chemical pollutants which serve to update exposure inputs for the formula cited above, many of which reference proprietary studies that are not readily available for review without purchase. States and tribes are now working to assess EPA default values relative to local and regional data for: body weight; drinking water consumption; fish consumption; trophic levels of fish in local waters and in representative diet; and toxicity values for non-carcinogenic and carcinogenic effects.
The West Virginia legislature recently directed the West Virginia Department of Environmental Protection to allow additional time to complete the assessment of local and regional data that is being developed prior to finalizing its water quality standards incorporating the 2015 human health criteria. In West Virginia, freshwater trout is sought after as a culinary delicacy. As for shark, that’s not typically on the menu.