Abstract
Concern has been expressed about the safety of formocresol use in pediatric dentistry.
Formaldehyde, a primary component in formocresol, is a hazardous substance and is
considered a probable human carcinogen by the International Agency for Research on
Cancer, Health Canada, the Agency for Toxic Substances and Disease Registry in the
U.S. Department of Health and Human Services, and the U.S. Environmental Protection
Agency. Humans inhale and ingest formaldehyde daily, however, and produce formaldehyde
during cellular metabolism. The human body is physiologically equipped to handle formaldehyde
through multiple conversion pathways. The resultant single carbon atom released during
metabolism is deposited in the “1-carbon pool,” which, in turn, is used for the biosynthesis
of macromolecules including DNA and RNA. Reevaluation of earlier research that examined
potential health risks associated with formaldehyde exposure has shown that this research
was based on flawed assumptions, which resulted in erroneous conclusions. The purpose
of this review was to examine more recent research about formaldehyde metabolism,
pharmacokinetics, and carcinogenicity. These results indicated that formaldehyde is
probably not a potent human carcinogen under low exposure conditions. Extrapolation
of these research results to pediatric dentistry suggests an inconsequential risk
associated with formaldehyde use in pediatric pulp therapy.
Key Words
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Article info
Footnotes
Conflict of Interest: Alan R. Milnes, DDS, PhD, reports no financial interests or potential conflicts of interest.
This article is being published concurrently in Pediatric Dentistry, May/June 2008; Volume 30, Issue 3. The articles are identical. Either citation can be used when citing this article.
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© 2008 American Academy of Pediatric Dentistry and American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
