Haven’t Hurricane Katrina victims suffered enough, without some government agency using junk science to add to their worries?
The Environmental Protection Agency has just completed a preliminary report suggesting that formaldehyde in the 120,000 trailers used to house Hurricane Katrina evacuees for years after the storm slightly elevated their risk of cancer. There’s only one problem: An analysis of the research cited in the EPA’s draft does not support its findings.
It looks like the EPA is taking pointers on alarmism from MSNBC’s “Toxic Tin Can ” theory on formaldehyde toxicity. MSNBC published “Are FEMA trailers ‘toxic tin cans?’” on July 25, 2006. Since then, the media has publicized sensational fears about the government-issued FEMA trailers housing residents evacuated by Hurricane Katrina, asserting that they had become “toxic” due to “elevated” levels of formaldehyde.
A primary component of particleboard adhesives, formaldehyde is also a naturally occurring chemical found at trace levels in human blood and important in many of our metabolic functions. The preliminary EPA evaluation suggests that continuous inhalation of 10-20 parts per billion over 70 years correlates with a 1 in 1000 increase in the risk of cancer, while exposure to lower levels can cause asthma. An analysis of the research cited in the draft, however, does not support the findings.
The most disconcerting inference, that formaldehyde causes cancer, is contradicted by multiple studies referenced in the draft. In order to assess cancer risk, the EPA primarily relied on a National Cancer Institute (NCI) study examining formaldehyde exposure in 25,000 chemical plant workers. Five of the nine cases of nasopharyngeal cancer (cancer in the back of the nose, known as NPC) claimed to prove causation were in a single chemical plant, while the total number of cases in the other plants was about the same as that expected in the US population. Pre- and post-employment screening of workers from the offending plant revealed that many were also exposed to silver and other metal particulates, which are known NPC risk factors, thus discrediting a formaldehyde causation. Moreover, additional research into higher formaldehyde exposures has not found a causal relationship with NPC. Relying on the same study to support an alleged correlation with leukemia, the EPA failed to consider that subsequent correction of that study resulted in a mortality rate comparable to that of the US population.
In their “Formaldehyde” chapter of Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants, the National Academy of Science (NAS) asserts that the risk of cancer and chronic disease from formaldehyde exposure “appears to be negligible at concentrations that do not produce chronic irritation and overt target tissue damage.” Yet, the level of formaldehyde exposure required to induce tissue damage greatly exceeds the concentrations found in the FEMA vehicles. The most recent research indicates that tissue damage in rats does not occur at levels below 2-6 parts per million, which is considerably higher than the 3-590 parts per billion (~.003-.59 ppm) the CDC measured in the FEMA trailers. Despite having the authoritative NAS testimony and such cutting-edge research, why does the EPA still insist that residential exposures to formaldehyde can cause cancer?
In addition, the EPA announced that formaldehyde inhalation causes and worsens asthma, but the literature simply does not agree. The National Academy of Science documented yet another scientific evaluation on an EPA draft issue. Comparing multiple research articles discussed in the draft document, they concluded:
…asthmatic individuals exposed to airborne formaldehyde at exposure concentrations at or below 3 ppm do not appear to be at greater risk of suffering airway dysfunction than nonasthmatic individuals
Thus, the studies do not support the EPA draft’s assertions that inhalation of formaldehyde can cause or exacerbate asthma at the low levels observed in residential settings.
Most recently, NASA presented many of these same flaws in their recently submitted formaldehyde draft commentary. NASA reminded the EPA that they completely ignored an assessment by the National Research Council, who identified “specific limitations” in the NCI study, namely the disproportionate number of NPC cases in one particular plant. Applying the same NAS document referenced herein, they assert that the EPA “overestimate[d] the risk [of cancer] at doses not associated with cytotoxicity.” Houston, we have a problem! Clearly, NASA's experts have serious concerns about the serious lack of sound science in this draft.
In short, the very science cited in the draft report specifically contradicts the findings publicly broadcast during the EPA’s phone conference. Yet the EPA chose to dismiss the conflicting opinions of other studies without providing an explanation as to how formaldehyde can cause cancer and asthma. (News media picked up this story and, predictably, ran overboard with it: the New Orleans Times-Picayune headline is illustrative: "Formaldehyde causes cancer, EPA declares.")
Why does the EPA ignore results from reputable groups that contradict its conclusions? It appears their goal is to expand their regulatory influence. By publicizing baseless “tin can” claims despite substantial disagreement in the literature, the EPA has needlessly heightened the fear of Hurricane Katrina victims who have already suffered enough.