By Pat Rizzuto
Aug. 8 — Formaldehyde can cause leukemia and at least two other types of cancer, the National Academies said in a review issued Aug. 8.
There is sufficient evidence from human studies to conclude that formaldehyde can cause nose and sinus cavity tumors as well as myeloid leukemia, the academies' National Research Council said.
That assessment upholds the conclusion the Department of Health and Human Services reached in 2011, when it classified formaldehyde as a known human carcinogen in its 12th Report on Carcinogens.
Formaldehyde is a major industrial “building block” chemical, because it is used to make many other chemicals. It also is used in the manufacture of pressed-wood products, such as particleboard, plywood and fiberboard; glues and adhesives; permanent-press fabrics; paper product coatings; some insulation materials; and as a preservative in mortuaries and medical laboratories, according to the National Cancer Institute.
Nearly 4 billion pounds of formaldehyde were made in or imported into the U.S. in 2011, according to information chemical manufacturers provided the Environmental Protection Agency.
Manufacturers include DuPont, Koch Industries Inc. and Momentive Speciality Chemicals Inc., which manufactured it in at least 16 facilities across the U.S. in 2011.
There are natural sources of formaldehyde as well. Humans, animals, bacteria and plants produce formaldehyde as part of cellular metabolism. It also is naturally present in fruits, vegetables, meats, fish, coffee and alcoholic beverages.
The academies convened a scientific committee that conducted two analyses of formaldehyde.
First, it critiqued HHS's conclusion using scientific information available as of June 12, 2011, when HHS released the 12th Report on Carcinogens.
The committee's deliberation focused on whether the National Toxicology Program (NTP), which prepares the Report on Carcinogens for review by the HHS secretary, did a good job.
Issues the committee examined included whether the NTP had identified the appropriate scientific studies, described them correctly, selected the most informative studies and adequately supported its conclusion that formaldehyde was a human carcinogen.
“The committee concludes that NTP comprehensively considered available evidence and applied the listing criteria appropriately in reaching its conclusion,” the academies review said. “The committee agrees with NTP's conclusion, which is based on evidence published by June 10, 2011,” it said.
The academies committee then conducted its own independent assessment of formaldehyde. That second analysis included scientific studies that were published after June 2011.
The committee said studies of workers, in particular, showed clear and convincing evidence that formaldehyde exposure can cause nose and sinus cavity cancers and myeloid leukemia.
“There may also be an increase of other lymphohematopoietic cancers, although the evidence is less robust,” the committee said.
Toxicity data from laboratory animal tests and mechanistic data, which describe the biological changes that could lead from formaldehyde exposure to cancer, provided additional information supporting the conclusion that formaldehyde exposure can cause cancer in people, the committee said.
Notwithstanding its support of HHS's final conclusion, the National Toxicology Program's guidance on how scientists should review human studies to determine whether they provide limited or suggestive evidence of carcinogenicity could be more clear, the committee said.
John Bucher, associate director of the National Toxicology Program, told Bloomberg BNA Aug. 8 the program's guidance will become clearer as it continues to craft systematic review procedures.
Systematic reviews provide step-by-step procedures analysts are to follow and questions they are to answer as they search the scientific literature to identify studies that may help them answer particular questions, determine the quality and applicability of different studies, select studies that will be used and weed out those that should be excluded and synthesize the evidence to reach a conclusion.
NTP recently said some systematic review procedures already can be used to analyze environmental health studies.
The academies formaldehyde report also provides useful examples of ways to lay out evidence and concisely get key information to readers, Bucher said.
The academies report “reflects, in many ways, what we are trying to do: making reports readable, concise and putting critical information up front,” Bucher said.
Bucher said the NTP is pleased that the academies' formaldehyde review substantiated again the scientific rigor the NTP employs as it prepares the congressionally mandated Report on Carcinogens.
On July 28, a different committee convened by the National Academies upheld the 12th Report's conclusion that styrene is “reasonably anticipated to be a human carcinogen”.
Congress ordered the academies review following industry opposition to the Report on Carcinogens classifications of formaldehyde and styrene. The omnibus appropriations bill for fiscal year 2012 (H. Rept. 112-331) directed HHS to spend $1 million to have the National Academies peer review both classifications.
Jennifer Sass, a senior scientist with the Natural Resources Defense Council, told Bloomberg BNA her organization is pleased by the academies' conclusion.
The academies' critiques of the formaldehyde and styrene classifications are the strongest possible statement from the scientific community, Sass said Aug. 8.
The nations' top scientists are saying government scientists are doing the best job possible of providing thorough and credible scientific information to the public about the health risks from chemicals, Sass said.
The Report on Carcinogens got it right the first time, she continued.
“Industry complaints and allegations add up to nothing more than a baseless defense of their toxic products,” Sass said.
She also commented on the academies' conclusion about myeloid leukemia.
“The chemical industry fought this tooth-and-nail, but science won the day, and now hopefully workers will be better protected and future cancers will be prevented,” Sass said.
Cal Dooley, president and chief executive officer for the American Chemistry Council, which represents major U.S. chemical manufacturers, issued a statement aimed at putting the academies critique in context.
“It is important to note that formaldehyde can continue to be safely used,” Dooley said.
The academies analysis discusses a potential hazard of formaldehyde, the academies' committee said in its own review.
Dooley said “much more information, including exposure, is needed to understand risk.”
“Formaldehyde has been thoroughly reviewed at the federal level and its use is subject to regulation in consumer products and in the workplace,” the chemistry council said. “The scientific literature is clear that there is no increased health risk from low-level exposures normally found in home or work environments.”
The academies' formaldehyde report is unlikely to end debates as to whether the chemical causes leukemia.
“Today's [National Research Council] report appears to conflict with the findings and recommendations made in a separate NRC committee's review of EPA's draft formaldehyde Integrated Risk Information System (IRIS) assessment,” said Jackson Morrill, director of ACC's Formaldehyde Panel in the statement the council circulated.
In 2011, an academies committee reviewed EPA's draft assessment and found “inconsistencies in the epidemiologic data, the weak animal data and the lack of mechanistic data,” he said.
Morrill referred to a report the academies issued in April 2011 that found the EPA failed to adequately support key conclusions, such as its finding that the chemical causes leukemia and other human cancers.
However, in 2011 Jonathan Samet, chairman of the committee that prepared the academies report, told Bloomberg BNA that the EPA failed to provide sufficient support for its conclusion that formaldehyde produces leukemias and lymphomas.
“EPA may be able to make that case, but the draft assessment the panel reviewed did not,” he said.
To contact the reporter on this story: Pat Rizzuto in Washington at firstname.lastname@example.org
To contact the editor responsible for this story: Larry Pearl at email@example.com
A prepublication copy of the academies' Review of the Formaldehyde Assessment in the National Toxicology Program 12th Report on Carcinogens is available at http://www.nap.edu/catalog.php?record_id=18948.
To view additional stories from Chemical Regulation Reporter ® register for a free trial now