Sunday, January 18, 2009

Formaldehyde Causes Genotoxic Effects at Exposure Levels about Half the OSHA Standard

Toxicology Volume 252, Issues 1-3, 30 October 2008, Pages 40-48
Genotoxic damage in pathology anatomy laboratory workers exposed to formaldehyde
Solange Costaa, b, , , , Patrícia Coelhoa, Carla Costaa, Susana Silvaa, Olga Mayana, Luís Silva Santosc, d, Jorge Gasparc and João Paulo Teixeiraa
aNational Institute of Health, Environmental Health Department, Praça Coronel Pacheco 15, 4050-453 Porto, Portugal
bEscola Superior de Biotecnologia da Universidade Católica Portuguesa, Rua Dr António Bernardino de Almeida, 4200-072 Porto, Portugal
cFaculty of Medical Sciences UNL, Department of Genetics, Rua da Junqueira 96, 1349-008 Lisboa, Portugal
dCentro Regional das Beiras, Universidade Católica Portuguesa, Estrada da Circunvalação, 3504-505 Viseu, Portugal

Formaldehyde (FA) is a chemical traditionally used in pathology and anatomy laboratories as a tissue preservative. Several epidemiological studies of occupational exposure to FA have indicated an increased risk of nasopharyngeal cancers in industrial workers, embalmers and pathology anatomists. There is also a clear evidence of nasal squamous cell carcinomas from inhalation studies in the rat. The postulated mode of action for nasal tumours in rats was considered biologically plausible and considered likely to be relevant to humans. Based on the available data IARC, the International Agency for Research on Cancer, has recently classified FA as a human carcinogen. Although the in vitro genotoxic as well as the in vivo carcinogenic potentials of FA are well documented in mammalian cells and in rodents, evidence for genotoxic effects and carcinogenic properties in humans is insufficient and conflicting thus remains to be more documented. To evaluate the genetic effects of long-term occupational exposure to FA a group of 30 Pathological Anatomy laboratory workers was tested for a variety of biological endpoints, cytogenetic tests (micronuclei, MN; sister chromatid exchange, SCE) and comet assay. The level of exposure to FA was evaluated near the breathing zone of workers, time weighted average of exposure was calculated for each subject. The association between the biomarkers and polymorphic genes of xenobiotic metabolising and DNA repair enzymes was also assessed. The mean level of exposure was 0.44 ± 0.08 ppm (0.04–1.58 ppm). MN frequency was significantly higher (p = 0.003) in the exposed subjects (5.47 ± 0.76) when compared with controls (3.27 ± 0.69). SCE mean value was significantly higher (p < r =" 0.384," p =" 0.001)" r =" 0.333," p =" 0.005)> Regarding the genetic polymorphisms studied, no significant effect was found on the genotoxic endpoints. The results of the present biomonitoring study emphasize the need to develop safety programs.


BrooklynDodger(s) comments: The Dodger(s) troll Toxicology and other laboratory journals for the few papers which involve a chemical with recognizable occupational or environmental exposures. It took several issues to find something. This suggest maybe most toxicology research generating peer reviewed literature is not relevant to public health.

Expansion of public health research beyond the United States is important to expanding our knowledge base. The EU, China and India may have to carry the field until US science recovers from the not yet over Bush Administration. This report is from Portugal.
The exposures averaged 0.44 ppm. This was an effect level for three types of genetic damage. Therefore, a NOAEL for genotoxicity was not established. A PEL to eliminate significant risk should be 10 to 100 fold below. The fact
of damage in circulating cells also contradicts the industry claim that formaldehyde is not absorbed into somatic tissues, an argument against the observed association between formaldehyde exposures and leukemia.

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