Photo: Child catches panfish at the mouth of Starkweather Creek where it flows into Lake Monona, July 2018
Our October 2018 article raised questions about exposures to toxic PFAS (per- and polyfluoroalkyl substances) in fish consumed from Starkweather Creek and where it discharges to Lake Monona. PFAS has leached into the creek for decades from fire-fighting foams used at Dane County Airport and Truax Air National Guard (ANG). A March 2018 report by Truax ANG consultants showed levels of just two kinds of PFAS (PFOA and PFOS) of 39,841ppt in shallow groundwater at the base—about 569 times above the EPA’s health advisory for these two compounds in drinking water. These levels were found just feet from the creek, along ditches and storm drains that lead directly to it.
In December 2018, Public Health Madison Dane County (PHMDC) posted a PFAS “fact sheet” with a short section titled “PFAS in Fish.” It stated that “The surface waters and fish near the airport would be expected to have detectable levels of PFAS due to the long-term use of PFAS containing firefighting foams at the site and nearby military facility.”
While this statement supports concerns raised in our post, immediately following it—employing risk assessment doublespeak we are sadly familiar with from this agency—PHMDC assured us that there is no risk: “Although detectable levels of contamination is [sic] likely, based upon the research conducted by the DNR, the surface waters and fish at sites near the airport are not expected to have levels of PFAS contamination that increase the potential risk to health from exposure.”
Huh? So PHMDC admits that PFAS in fish is “expected” at “detectable” levels—which means fish consumers will be exposed some level of PFAS—but then with no data whatsoever relevant to Starkweather Creek, assures us that these unknown levels are not expected to increase risks.
This is not only disingenuous doublespeak—it’s unscientific and ill-informed.
PHMDC assurances based on no data
Firstly, again, PHMDC has no data on which to claim that health risks from eating the fish from Starkweather Creek, which flows through the airport and Truax Air National Guard sites, are “not expected.” Drawing this conclusion without any data at all is not science–it’s just speculation. It is also ethically irresponsible.[1]
Further, extrapolating this conclusion from the 2016 DNR study alone is inappropriate and indicates that PHMDC has not reviewed the numerous government reports and growing body of peer-reviewed scientific literature on PFAS levels found in waters and fish downstream of airports and military sites.[2]
The DNR study stated, correctly, that “[F]ish presently represent a major PFC exposure route for humans…Potential exposure due to fish consumption is a threat to Wisconsin anglers and their families, as several studies have demonstrated that PFCs can accumulate in freshwater fish to concentrations that pose a threat to human health.”
The DNR study also noted—again correctly—that “proximity to PFC (an old term for PFAS) is an important factor affecting concentrations.” Supporting this conclusion, the three areas where fish had the highest PFAS levels were in the Mississippi River downstream of 3M, which manufactured PFAS for a variety of uses beginning in the 1950s.[3] This section of the river is approximately 8-10 miles from 3M, showing how far PFAS compounds can travel in water. About two miles from 3M, fish in Lake Elmo had PFAS levels so high that a “do not eat any fish” advisory was placed on the entire lake.
PHMDC’s assurances that waters and fish near the airport “are not expected” to have high levels of PFAS and therefore would not pose public health risks were, according to the fact sheet, “based upon the research conducted by the DNR.” But the DNR study didn’t test PFAS from any sediments, surface waters and/or fish anywhere near any airports or military sites.
High PFAS levels found near military bases and airports
If PHMDC had considered any of the many other government reports and scientific studies on PFAS in fish, they would know that waters, sediments and fish immediately downstream of airport and military sites have among the highest PFAS levels of any PFAS sites ever studied—many orders of magnitude above background PFAS levels.
For instance, a 2016 study by the Air Force Civil Engineer Center that assessed PFAS levels at ten military bases found that the median PFOS levels in surface waters were 2,170 ng/L (ppt) and the maximum levels found were 8,970,000 ng/L (ppt).[4] A study of water, sediments, and fish downstream of an Air Force base in Louisiana found PFOS levels in surface water downstream of fire training areas of up to 1,800 ng/L (ppt)—and a sunfish at this site had 9,349 ppb (9,349,000 ppt) PFOS in its tissues. At Wurtsmith Air Force Base in Michigan, up to 9,580 ppb (9,580,000 ppt) PFOS was found in fish and at Barksdale Air Force Base in Louisiana, up to 9,349 ppb (9,349,000) PFOS was found. Very elevated levels of PFOS in fish have also been measured downstream of airports that used fire-fighting foams containing PFAS.
These amounts are hundreds and/or thousands of times above surface water and fish PFAS advisories already developed (or proposed) in some other states. Michigan, for instance, has a standard of 12 ppt for PFOS in surface water, developed to protect fish consumers as well as biota.
Wisconsin’s limited fish PFAS advisories totally inadequate and unprotective
PHMDC’s fact sheet statement that only the three Mississippi River sites had PFAS levels warranting health advisories, seemingly intended to downplay concerns, is also not reassuring. Wisconsin PFAS fish advisories (issued only for the Mississippi river) are orders of magnitude higher (less protective) than PFAS fish advisories issued in other states. Based on other states’ more protective fish PFAS advisories, nearly all of the water bodies in the DNR study would be on fish advisory.[5]
Has PHMDC even reviewed studies on PFAS levels found near military bases or considered fish advisories in other states? The fact sheet suggests that instead of doing so, PHMDC is comfortable assuring the public, without any data, that though they expect there will be exposures, these exposures will be harmless.
Why does our public health department always downplay–or outright deny–any risks to public health from exposures to toxic chemicals? In most cases, they seem to be protecting polluting industries from blame or responsibility. In this case, who is the agency protecting? The military? Dane County, which owns the airport and Truax base land? Clearly it’s not the public they are charged to serve.
Postscript: Fish will be tested because citizens demanded it, not because of PHMDC proactivity
Even though they have already assured the public that they expect the PFAS levels in fish downstream of the Dane County airport and Truax ANG will pose no health risks, testing will be done in spring 2019. This testing is only being done because we repeatedly asked for it–not because PHMDC initiated it in effort to protect public health.
After DNR and the county ignored our repeated requests since spring 2018 to test Starkweather fish, we eventually asked PHMDC, who said they couldn’t do it. In October 2018, Alder David Ahrens proposed a city budget amendment of $5000 for fish testing–and the amendment was approved by the Common Council in November.
PHMDC, however, said they had no resources or capacity to catch or test fish [6], so they decided to turn the $5000 over to the DNR; the agency wasn’t planning to do the testing otherwise. Why would city money be turned over to DNR for a fish study DNR should be funding? Do we trust DNR to do the appropriate testing–and to share the full results honestly and transparently with the public? Their track record isn’t good.
Further, given that PHMDC has already predicted that PFAS levels found in the fish will pose no public health risks, will they assure that testing is done appropriately, share results openly with the public, and interpret results without bias? It seems very unlikely.
Finally, while waiting for the testing, PHMDC advises that people “follow current fish consumption advisories” for PCBs and mercury. Unfortunately, following these advisories will not protect fish consumers from PFAS exposures, and may actually increase them. PFAS fish studies (including the DNR’s) have shown that PFAS follow different bioconcentration and bioaccumulation patterns than PCBs and mercury. In many studies, panfish and other smaller fish (not the larger fish, which tend to accumulate more PCBs and mercury) were found to have higher levels of PFAS. This renders the existing fish advisories totally inappropriate for PFAS, since they typically advise people to limit consumption of larger fish but often allow “unlimited consumption” for smaller fish (for some groups). Existing advisories may actually encourage people to eat more smaller fish with higher PFAS levels.
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[1] The term “detectable” is somewhat meaningless, given that detection limits vary depending on the lab that does the testing and the analytical methods used and available (which also change all the time).
[2] The 2016 DNR paper was published in a DNR report, not a peer-reviewed scientific journal.
[3] 3M has made fire-fighting foam (aqueous film-forming foam, AFFF) for the military, including Navy and Air National Guard, since the 1960s.
[4] These high levels are particularly remarkable given that this study excluded sites with AFFF releases from fire-training areas, and the sites’ AFFF releases occurred (purportedly) between 1970-1990.
[5] In 2007 the DNR developed PFOS advisories only for a stretch of the Mississippi River downstream of 3M—advising “unlimited consumption” only for fish with PFOS levels under 38 ppb, increasing consumption restrictions for fish with from 38 ppb to 700 ppb, and “do not eat” for fish with levels over 700 ppb. The agency (DNR) has not yet developed statewide PFAS fish advisories (DNR told us they are waiting for the Department of Health Services to develop a reference dose; why haven’t they done so yet?)
In comparison, Minnesota’s 2018 advisories recommend “unlimited consumption” only for fish with PFOS levels under 10 ppb, increasing limitations on consumption of fish levels from 10 ppb up to 200 ppb, and “do not eat” for fish with over 200 ppb. Even more conservative advisories being drafted by New Jersey recommend unlimited fish consumption only if fish have less than .56 ppb PFOS. New Jersey’s draft recommendations recommend that “high risk populations” (infants, children, nursing mothers, women of child-bearing age) not eat any fish with PFOS levels over 17 ppb.
[6] It is more than a little troubling that our city/county public health department, in a county that includes numerous lakes, rivers, and creeks that are heavily fished–including by a large number of minority and poor subsistence anglers– does not have the resources, knowledge and capacities to test fish in order to protect local fish consumers and their families from toxic exposures. This public health department has existed for decades. It’s time political leaders work to assure that it has the capacity to test fish in local waters so that we don’t have to rely on the DNR for this testing. To date the DNR’s testing of Madison/Dane County waters’ fish has been sparse and totally inadequate.
