Occupational exposure toxicology

For all agents of concern in occupational toxicology (except therapeutics), the major route by which the general population is most frequently exposed is the percutaneous (dermal) route. Brown (1980) has previously reviewed background incidence data on pesticides, for example, that show such exposures to be common. Dermal (or topical) drugs are not as common, but are certainly numerous. 

Most of the assessment of toxicology and safety of therapeutics is focused on the patients who are to benefit from the new medicine. However, there are two other groups of individuals (each of which has different exposure profiles) that one must be concerned about the healthcare providers (nurses, pharmacists and physicians) who provide and/or administer the drugs and the individuals involved in manufacturing them. The concerns here are in the realm of occupational toxicology. 

Modem toxicology has its roots in the occupational environment. The earliest recorded observations relating exposure to chemical substances and toxic manifestations were made about workers. These include Agricola s identification of the diseases of miners and Pott s investigation of scrotal cancer incidence among chimney sweeps. Occupational toxicology, as its name implies, concerns itself with the toxicological implications of exposure to chemicals in the work environment. 

Galer, D. M., Leung, H.-W., Sussman, R.G. and Trzos, R.J. (1989). Scientific and practical considerations for developing occupational exposure limits for chemical substances. Presentation to the Second Annual Occupational Toxicology Roundtable, November 21, 1989, Rahway, New Jersey. 

The goal of occupational toxicology is to ensure work practices that do not entail any unnecessary health risks. To do this, it is necessary to define suitable permissible levels of exposure to industrial chemicals, using the results of animal studies and epidemiological studies. These levels can be expressed by the following terms for allowable concentrations. 

Thorne, P. S. Occupational toxicology. In Casarett and Doull s Toxicology The Basic Science of Poisons, 6th ed., C. D. Klaassen, ed. New York McGraw-Hill, 2001, pp. 1123-1140. Doull, J. Recommended limits for occupational exposure to chemicals. In Casarett and Doull s Toxicology The Basic Science of Poisons, 6th ed., C. D. Klaassen, ed. New York McGraw-Hill, 2001, pp. 1155-1176. 

The book provides a short, authoritative overview of the information available on the occupational toxicology of many important chemical exposures. Consideration of reproductive and developmental toxicology is limited. 

Phase II Find out all occupational toxicology data from available sources, treating the route of exposure as highly significant. 

See also American Conference of Governmental Industrial Hygienists American Industrial Hygiene Association Exposure Criteria International Labour Organization (ILO) National Institute for Occupational Safety and Health Occupational Toxicology Occupational Exposure Limits. 

See also Occupational Exposure Limits Occupational Toxicology. 

See also American Conference of Governmental Industrial Hygienists Exposure Exposure Assessment Occupational Toxicology. 

When choosing a study for applications in occupational toxicology, it is important that the exposure protocol be relevant to the exposure scenario in the workplace. The route, duration, and frequency of exposure can have a significant effect on the toxicity of a xenobiotic agent. 

Several advanced courses have been developed such as Reproductive Developmental Toxicology Endocrine Disrupters, Clinical Occupational Toxicology Occupational Exposure Limits and Life Cycle Assessment. 

Ballantyne, B. and Salem, H., Experimental, clinical, occupational toxicology and forensic aspects of hydrogen cyanide with particular reference to vapor exposure, in Inhalation Toxicology, Second Edition, Salem, H. and Katz, S., Eds., Taylor and Erancis, Boca Raton, EL, 2005, pp. 709-794. 

A. Elimination or reduction of further exposure is a key treatment intervention in occupational toxicology. This includes prevention of exposure of coworkers. The Occupational Safety and Health Administration (OSHA) may be of assistance and should be notified immediately about an ongoing, potentially life-threatening workplace exposure situation. Contact information for region OSHA offices is listed in Table IV-3. Workplace modification and control, especially the substitution of less hazardous materials, should always be the first line of defense. Worker-required personal protective equipment is, in general, less preferred. 

Toxicology Exposure is by inhalation. Cobalt causes skin allergies and irritation, and its dust causes occupational asthma. The lARC decided that cobalt metal powder and cobaltous oxide are A3 confirmed carcinogenics in animals, and they are possible human carcinogens [20]. 

Toxicology Exposure is by inhalation. MMA is a strong irritant (eyes, mucous membrane and skin), and a toxicant affecting nerve cells and causing occupational asthma, foetal toxicities, and possibly cancer [59]. I ARC concluded that there is no adequate evidence proving the carcinogenicity of MMA [60]. 

Occupational toxicology focuses on identifying and preventing effects of hazardous materials in employee populations. The scope of occupational toxicology extends, however, beyond the woikforce to the workers families, to the surrounding community, and to the population(s) which may subsequently encounter the product or material. In theory, any identifiable and/or measurable effect is undesirable. In practice, acceptable exposure levels or limits can be established, and are established, to protect these populations from adverse health effects. 

Workers in the metals treatment industry are exposed to fumes, dusts, and mists containing metals and metal compounds, as well as to various chemicals from sources such as grinding wheels and lubricants. Exposure can be by inhalation, ingestion, or skin contact. Historically, metal toxicology was concerned with overt effects such as abdominal coHc from lead toxicity. Because of the occupational health and safety standards of the 1990s such effects are rare. Subtie, chronic, or long-term effects of metals treatment exposure are under study. An index to safety precautions for various metal treatment processes is available (6). As additional information is gained, standards are adjusted. 

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