Evaluation chemical irritation

Alarie, Y. (1981a). Toxicological evaluation of airborne chemical irritants and allergens using respiratory reflex reactions. In Inhalation Toxicology and Technology (Leong, B.K.J., Ed.). Ann Arbor Science, Arm Arbor, pp. 207-231. 

However, since the act of sensation is an interaction of an observer with a stimulus, the two approaches often end up using similar methods (e.g., scaling) to provide similar information (e.g., observer response as a function of stimulus concentration). Because of this parallel orientation in methods, and because of the concurrent advances recently made in both areas, we have integrated results from the two fields in this paper. The first section will focus on psychophysical characterization of oral chemical irritants. The final section will discuss the development of a new sensory method for evaluation of ground red pepper heat. 

In additional EPA studies, subchronic inhalation was evaluated ia the rat for 4 and 13 weeks, respectively, and no adverse effects other than nasal irritation were noted. In the above-mentioned NTP chronic toxicity study ia mice, no chronic toxic effects other than those resulting from bronchial irritation were noted. There was no treatment-related increase ia tumors ia male mice, but female mice had a slight increase in bronchial tumors. Neither species had an increase in cancer. Naphthalene showed no biological activity in other chemical carcinogen tests, indicating Htde cancer risk (44). No incidents of chronic effects have been reported as a result of industrial exposure to naphthalene (28,41). 

Galer, D.M., Curren, R., Gad, S.C., Gautheron, P., Leong, B., Miller, K., Sargent, E., Shah, P.V, Sina, J. and Sussman, R.G. (1993). A 10-company collaborative evaluation of alternatives to the eye irritation test using chemical intermediates. Alternative Methods Toxicol. 9 237. 

Additionally, the test materials used in the validation process should be as closely related as possible to the characteristics of the unknowns to be tested. It is clear from the literature, for instance, that many cytotoxicity assays give good correlations with the in vivo ocular irritancy data for surfactants, but the correlations fail when compounds from other chemical classes are tested. Since any particular assay may be used differently by individual safety assessment programs, users must evaluate potential methods under conditions likely to be encountered in their own situations. 

To test the irritancy potential of substances, two tests which can reliably distinguish between skin corrosives and noncorrosives are endorsed by the European Centre for the Validation of Alternative Methods (ECVAM). The testing procedures are based on the transcutaneous electrical resistance (TER) measurements of rat skin and on a human skin model. Both test systems [141-145] will be briefly outlined below. Nevertheless, these tests are not suited for the group of mild irritants which do not induce an acute effect on the barrier function. For those substances, new markers need to be evaluated. First results are available for heat shock protein 27 where higher levels were observed in skin models after exposure to mildly irritating chemicals [146, 147]. 

K. Meyer, C. Steinhoff, C. Tornier, B. De Wever, and M. Rosdy. Assessment of the skin irritation potential of chemicals by using the SkinEthic reconstructed human epidermal model and the common skin irritation protocol evaluated in the ECVAM skin irritation validation study. Altern. Lab. Anim. 34 393-406 (2006). 

Ideally, a full data set should be available for the hazard assessment of a chemical substance, including animal tests to evaluate the toxicokinetics and the following toxicological properties acute toxicity, irritation, sensitization, toxicity following repeated exposure to the substance, mutagenicity and genotoxicify, carcinogenicity, and effects on fertility and fetal development. 

Sporadic cases of dermatitis due to primary irritation by a-chloroacetophenone have been reported. Allergic contact dermatitis to this substance in chemical Mace has been documented by patch test evaluation, and it is said to be a potent skin sensitizer. ... 

After completion of Volume 1, three new panels were established to Identify and assess evidence on the possible long-term health effects or delayed sequelae of the three chemical classes tested. This was done over a period of a year, during which each panel met three times. Pertinent material was examined to evaluate the possibility that experimental exposure of soldiers may have resulted in untoward health effects. The three panels were separately concerned with four cholinesterase reactivator chemicals (oximes) two types of psychochemicals (phencyclidine and dlmethylheptylpyran and congeners), administered In pure form, as opposed to street drugs and mustard gas and several lacrlmatory and respiratory irritants (such as CN, CS, CR, and CA). 

Data on the Irritants are insufficient to evaluate their mutagenicity, carcinogenicity, or other long-term effects. Tests of all theses chemicals involved few exposures and low doses. 

In general, the Committee found insufficient evidence to evaluate these chemicals, except mustard gas. Mustard gas 1b an experimental mutagen and human carcinogen at high doses. Data on the other irritants are insufficient to evaluate their mutagenicity, carcinogenicity, or other long-term effects. Tests of all these chemicals involved few exposures and low doses. 

The present report evaluates toxicologic and epidemiologic data relevant to the testing of approximately 750 subjects exposed to cholinesterase reactivators, about 260 exposed to psychochemicals, and 1,500 exposed to irritants or vesicants. A remaining group of subjects used largely In tests involving placebo or Innocuous chemicals or conditions is available for comparison and will be discussed In Volume 3. 

Vapor (Gas) Irritant Characteristics — Since MSDSs often provide non-qualifying statements, the most appropriate of five statements listed below is given. (Source National Academy of Sciences, Committee on Hazardous Materials, "Evaluation of the Hazard of Bulk Water Transportation of Industrial Chemicals, A Tentative Guide," Washington, D.C., 1970.)... 

We are now able to know the intimate nature of the chemical aggression by an irritant or a corrosive on the fragile biological structures of an eye. We can also evaluate the strength of this aggression. 

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