Respiratory tract cancers

A health survey of 4,280 people exposed to trichloroethylene and other contaminants through drinking water in three states (Illinois, Indiana, and Michigan) has been completed (ATSDR 1994). An increase in respiratory tract cancers was observed in males. The study authors concluded that based on the incidence of smoking in the population "it would be inappropriate to relate this excess solely to trichloroethylene exposure."... 

Conolly, R.B., J.S. Kimbell, D. Janszen, et al. 2004. Human respiratory tract cancer risks of inhaled formaldehyde Dose-response predictions derived from biologicaUy-motivated computational modehng of a combined rodent and human dataset. Toxicol. Sci. 82 279-296. 

Wada et al. extended Yamada s observations on the same men,7 finding 33 deaths from respiratory tract cancers for 1952-1967, compared with an expected 0.9, a relative risk of nearly 37. For 960 employees not exposed to H, Wada et al. found only three deaths from respiratory tract cancer, compared with 1.8 expected. These data point to a connection between long, low-dose exposure to H and later cancer, especially in the respiratory tract. 

Six cases of respiratory tract cancer were reported among benzoyl chloride production workers in two small plants in Japan. The cases occurred in people aged < 44 years, three of whom were nonsmokers (lARC, 1982, 1987a). 

Rats exposed to tobacco-derived nitrosamines developed tumors at the nose, mouth, esophagus, lung, and pancreas. Tobacco-derived nitrosamines caused upper respiratory tract cancers in exposed hamsters. 

Exposure to mist sprays or insoluble oils used as coolants, cutting fluids, and lubricants in machine operations are usually not harmful to the respiratory tract, although worker discomfort occurs at oil mist levels above 5mgm . Mineral oil droplets <5 pm in diameter may be inhaled and result in fibrotic nodules, paraffinomas, or in lipoid pneumonitis. There was no evidence that machinists exposed to cutting-oil mists had any unusual mortality from respiratory tract cancer. 

Chronic skin exposure to turpentine may produce a hypersensitivity reaction, with bullous dermatitis and/or eczema. A case-control study of workers in particle-board, plywood, sawmills, and formaldehyde glue factories demonstrated a statistically significant association between chronic exposure (longer than 5 years) to terpenes (the principal component of turpentine) and the development of respiratory tract cancers. 

R. B. Conolly, J. S. Kimbell, D. Janszen, P. M. Schlosser, D. Kalisak, J. Preston and F. J. Miller, Human Respiratory Tract Cancer Risks of Inhaled Formaldehyde Dose-Response Predictions Derived from Biologically-Motivated Computational Modeling of a Combined Rodent and Human Dataset, Toxicological Sciences, 82, 279-296. 

Collins JJ, Acquavella JF, Esmen NA. 1997. An updated meta-analysis of formaldehyde exposure and upper respiratory tract cancers. J Occup Environ Med 39 639-651. 

In contrast to battlefield exposures, smdies of factory workers involved in the production of mustard have shown a definite link between prolonged exposure to low doses of mustard and cancer. Several studies have provided evidence of an increased risk of respiratory tract cancers in factory workers. " ° Easton et al. found a 45% increase in death due to lung cancer, a 170% increase in death from cancer of the larynx, and a 450% increase in death from cancer of the pharynx, compared with... 

The failure to explain the observed tumorigenicity of CSC in the mouse-skin bioassay by consideration of the following tobacco smoke systems led to the inclusion of ciliastasis by various water-soluble vapor-phase (VP) tobacco smoke components in an attempt to explain the causation of respiratory tract cancer in smokers ... 

The volatile NNAs in tobacco smoke, usually reported as tobacco smoke components that contribute to the health problems related to smoking, particularly the cigarette smoke-respiratory tract cancer problem, are the first seven listed in Table XV-2. 

These exposure estimates [for benzo[a]pyrene] and the determinations of the tumorigenic potential of [polycyclic aromatic hydrocarbons] in bioassays strongly suggest that [polycyclic aromatic hydrocarbons] play a significant role in the induction of respiratory tract cancer in smokers... 

Weekly administration of 3 mg of 77/-dibenzo[c,g]carbazole for 15 weeks resulted in 13% more animals dying with respiratory tract cancer than died with same dose level of B[a]P. With lower total dose levels (15 mg) of B[a]P only, 30% of the animals developed respiratory tract tumors vs. 89% of the animals treated with the same dose of 7//-dibenzo[c,g] carbazole. The tumors in the 77/-dibenzo[c,g]carbazole group appeared earlier than those in the B[a]P-treated group. 

Inhaled cigarette smoke is the responsible agent for respiratory tract cancer, particularly squamous cell carcinoma of the lung, in smokers. It was implied in the late 1950s and in the 1960s that the responsible agent in MSS may be the PAHs, particularly B[a]P. 

Despite the contradictory evidence that precludes the involvement of NNAs either collectively or individually not only in various bioassays with laboratory animals but also in respiratory tract cancer in cigarette smokers, some investigators still maintain that the tumorigenicity of cigarette smoke in humans is due to its PAH content and its content of the TSNA, NNK. 

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