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R O Beauchamp

Publications and source records attributed to R O Beauchamp.

10 recordsLinked to original sources

A review of the chronic toxicity, carcinogenicity, and possible mechanisms of action of inorganic acid mists in animals.

Occupational exposure to inorganic acid mists containing sulfuric acid has been associated with increased laryngeal cancer. The primary objective of this review was to compile the literature regarding chronic toxicity and carcinogenicity of inorganic acid mists in laboratory animals. Several chronic toxicity studies had exposures of 1 year or longer. Whereas numbers of animals were limited, no evidence of neoplastic or preneoplastic lesions was reported. Two studies evaluated the carcinogenicity of inorganic acid mists in rats; however, one was limited by a short duration of exposure and the other did not achieve a maximum tolerated dose. A large lifetime study in hamsters evaluated the carcinogenicity of 100 mg/M3 sulfuric acid mist, as well as its ability to act as a promoter or co-carcinogen for benzo(a)pyrene. No evidence of carcinogenic potential was shown. Although an increase in papillomas was noted in the benzo(a)pyrene + H2SO4 group, the co-carcinogenic or promoting potential was considered equivocal. Thus, no evidence from experimental animals strongly supports or refutes the induction of cancer by inorganic acid mists. A possible mechanism that could be associated with inorganic acid mist carcinogenicity relates to the genetic consequences of lowering the pH. Reduced pH can induce chromosomal aberrations, enhance depurination, and deamination of cytidine in DNA. This mechanism has not been evaluated in tissues of the respiratory tract.

Aerosols↗

A critical review of the toxicology of glutaraldehyde.

Glutaraldehyde, a low molecular weight aldehyde, has been investigated for toxicity in humans and animals. Examination of this dialdehyde was indicated from previous studies with other aldehydes in which carcinogenicity of formaldehyde and toxicity of acetaldehyde and malonaldehyde have been disclosed. Information gaps concerning the actions of glutaraldehyde have been identified in this review and recommendations are suggested for additional short- and long-term studies. In particular, information regarding irritation of the respiratory tract, potential neurotoxicity, and developmental effects would assist in a complete hazard evaluation of glutaraldehyde. Further study related to disposition, metabolism, and reactions of glutaraldehyde may elucidate the mechanism of action.

Animals↗

A critical review of the literature on acrolein toxicity.

A detailed literature review of human and animal toxicity studies of acrolein is presented, and information gaps identified that call for further investigation. Specific recommendations are suggested for additional short-/long-term studies, including chemical disposition and cytogenetic investigations. Two bibliographies are provided indicating the scope of the review: (1) literature actually cited and (2) literature examined but not included.

Acrolein↗

A critical review of the literature on hydrogen sulfide toxicity.

The information available on the biological activity of hydrogen sulfide has been examined for present status of critical results pertaining to the toxicity of hydrogen sulfide. This review of the literature is intended as an evaluative report rather than an annotated bibliography of all the source material examined on hydrogen sulfide. The information was selected as it might relate to potential toxic effects of hydrogen sulfide to man and summarized, noting information gaps that may require further investigation. Several recommendations are listed for possible consideration for either toxicological research or additional short- and long-term tests. Two bibliographies have been provided to assist in locating references considered in this report: (1) literature examined but not cited and (2) reference citations. The majority of the references in the first bibliography were considered peripheral information and less appropriate for inclusion in this report.

Abnormalities, Drug-Induced↗

A critical review of the literature on nitrobenzene toxicity.

This literature review encompassing information available through 1980 and limited coverage in 1981, emphasizes results useful in assessing the potential toxic effects of nitrobenzene to man. Nitrobenzene exposure in man or experimental animals is most often associated with methemoglobinemia. Histopathologic changes also are observed in the hemato-lymphoreticular system, central nervous system, and liver. In addition, lesions have been reported in adrenals and testes. No information was found on carcinogenic or teratogenic potential, fertility, or reproductive effects of nitrobenzene. Results from Ames Salmonella assay are negative but test procedures are questionable; metabolites give positive results. Metabolism of nitrobenzene involves either oxidation or reduction yielding p-aminophenol and p-nitrophenol, and other reduced intermediates. From the foregoing, several aspects of nitrobenzene toxicity have been identified which warrant further study. Recommendations are made for chronic and subchronic exposure of test animals via inhalation to assess various toxicological endpoints. In addition, the relationship of nitrobenzene metabolism to its toxicity needs to be established. Genotoxic effects of nitrobenzene also need study.

Abnormalities, Drug-Induced↗