Fish consumption rate: Why 20 years of studies is enough

Over at Keep Our Seafood Clean, we’ve taken a look at the current debate in the state legislature over funding a new study on fish consumption rates in Washington. This isn’t a new debate, but after twenty years of study, some are still calling for “more study.”

Catherine O’Neill’s broad piece on the fish consumption rate has a great explanation on all of the attacks on previous fish consumption studies and why decades of work is enough.

Throughout the process of updating the FCR in Washington, there have been broadsides on the science that supports increased rates.

Although the relevant surveys of tribal fish consumption were carefully conducted to ensure their scientific defensibility, and have consistently been found to meet EPA’s (and sister states’) standards in this regard, their validity has nonetheless continued to be challenged by industry and individuals.

Ecology’s initial (Fish Consumption Rate Technical Support Document) FCR TSD considered three studies of tribal fish consumption and one study of Asian and Pacific Islanders in King County, finding each of these four studies to be scientifically defensible. In its FCR TSD, Ecology developed a set of criteria to determine the technical defensibility of fish consumption survey data, to be used in assessing the data’s relevance and appropriateness to the regulatory context in Washington, i.e., for use in standards for water quality, surface water cleanup, and sediment cleanup. …

As documented at length in the FCR TSD, each of the tribal studies considered… was found to have “satisfied” Ecology’s measures of technical defensibility.

The support for the previous studies has been deep and wide:

Moreover, the scientific defensibility of each of the tribal studies had previously been considered and affirmed in various assessments by EPA and by sister states. After an evaluation of the surveys according to five criteria, including the study’s “soundness,” “applicability and utility,” “clarity and completeness,” its handling of “uncertainty and variability,” and whether the study’s methods and information were “independently verified, validated, and peer reviewed,” EPA selected each of the tribal studies for inclusion in its general guidance document for conducting exposure assessments, the Exposure Factors Handbook. EPA Region X, moreover, recommends the Tulalip/Squaxin Island and Suquamish studies in its guidance for cleanups in Puget Sound, giving “highest preference” to these “well-designed consumption surveys.” Oregon’s independent Human Health Focus Group conducted an extensive year-long review and found each of these studies to be scientifically defensible, deeming them both “reliable” and “relevant.”

But, yet:

Still, the scientific defensibility of the tribal studies has been questioned, repeatedly, by individuals and industry as part of the Washington process. Some commenters asked that the tribal survey data be “verified” or sought additional “peer-reviewed studies generated through traditional means.”

Some people have asked that all the year’s of previous study be treated differently that other studies:

Some commenters called for the raw data (as opposed to the studies summarizing the survey results) to be “turned over” for “independent review” – a highly unusual request in general, given the ethical protocols that govern studies with human subjects, and a request in this context that is at the very least insensitive, given tribal populations’ understandable mistrust of handing over their raw “data” to outsiders.

To the credit of the state, the pushback against questioning these studies has been consistent. For example, in terms of turning over the “raw data”:

Ecology also called upon experts at the University of Washington School of Public Health to explain the standard practice in the field with respect to custody of survey data – an explanation that confirmed the inappropriateness of requests that the raw data be turned over to the public.

Even as late as last fall, Ted Sturdevant, then director of the Washington Department of Ecology told a house committee: “I’m confident that the studies that we’re relying on were done with all appropriate scientific rigor.”

So, why the need for even more study?