Utilization of transparent, objective and modern scientific approaches to draw conclusions regarding human health risk is critical to developing sound regulatory decisions. Throughout the EPA, the application of scientific information to underpin regulatory activities has often been inconsistent and unclear; leading to concerns regarding how the Agency incorporates the best available science, how it evaluates the quality of that science, and how it applies 21st century scientific practices to draw conclusions.
The ACC Formaldehyde Panel (the Panel) has regularly met with EPA scientists related to the Integrated Risk Information System (IRIS) program, regarding its subjective use of available science to assess chemical hazards. Unfortunately, EPA IRIS has regularly set values that are below natural background levels and not indicative of human health risk associated with real world exposures.
Perhaps the most telling example can be found in the case of formaldehyde. Formaldehyde has been the subject of scientific study for years and the large body of evidence shows that the levels of formaldehyde most people encounter on a daily basis do not cause adverse health effects. For more than a decade, the Panel has conducted scientific research and engaged directly with EPA’s IRIS program to understand the scientific information being relied on to draw conclusions. This peer reviewed and publicly available science, summarized in over 30 scientific articles, illustrates that formaldehyde does not cause leukemia and that there are clearly defined safe thresholds for formaldehyde exposure.
Yet, EPA’s proposed 2010 risk value suggests that human breath poses an unacceptable risk of cancer. The Panel has experienced considerable difficulty understanding what data EPA may be relying on and how the Agency has ensured that the highest quality and most relevant science is informing its decisions. The truth is, formaldehyde is a natural part of our world and the illogical findings of IRIS are not. How can human breath cause cancer? Formaldehyde is found in every living system – from plants to animals to humans – produced as part of our normal metabolic process. If a person inhales formaldehyde, the body breaks it down rapidly, just as when it is naturally produced in our bodies.
In addition to incorporating modern scientific knowledge, the Panel also recognizes the importance of adequate data access and ensuring regulatory decisions are based on high quality and reproducible data. There have been several examples in recent years where publicly-funded research data were not provided in a transparent or timely manner and erroneous evaluations and interpretations persisted. Importantly, in multiple instances once the underlying data were made available, sometimes after multiple years of requests, the data were found to be severely flawed. In several cases, the findings when re-evaluated did not support the original studies’ conclusions.
Two examples are provided below:
- Mundt et al., conducted additional and refined analysis on the underlying data from the Zhang et al. (2010) study provided by NCI and relied upon in the IRIS assessment to identify formaldehyde as a leukemogen. Mundt et al.’s analysis observed no association between individual formaldehyde exposure estimates and frequency of aneuploidy, which the original study authors suggested were indicators of myeloid leukemia risk.
- Checkoway et al. sought to replicate the findings reported by Beane Freemen et al. (2009) and relied upon in the underlying data provided from NCI. The findings from this re-analysis fail to support the original study hypothesis that formaldehyde causes acute myeloid leukemia. Specifically, the results indicated that acute myeloid leukemia was unrelated to “peak” or any other formaldehyde metric including the conventional cumulative exposure.
As demonstrated by the formaldehyde example when data are not made available in a timely manner and modern approaches aren’t used, it can lead to conclusions that lack scientific rigor. The public needs to have confidence that EPA, too, will set acceptable levels that are also based on relevant, best available science. The Panel encourages EPA and other agencies to consider the entire weight of evidence for all chemical evaluations, including formaldehyde.
 Mundt, K., Gallagher, A., Dell, L., Natelson, E., Boffetta, P., and Gentry, R. Does occupational exposure to formaldehyde cause hematotoxicity and leukemia-specific chromosome changes in cultured myeloid progenitor cells? (2017) Critical Reviews in Toxicology. Aug;47(7):592-602.
 Checkoway, H., Dell, L.D., Boffetta, P., Gallagher, A.E., Crawford, L., Lees, P.S., and Mundt, K.A. (2015). Formaldehyde exposure and mortality risks from acute myeloid leukemia and other Lymphohematopoietic Malignancies in the US National Cancer Institute cohort study of workers in Formaldehyde Industries. Journal of Occupational and Environmental Medicine, 57(7), 785-794.