Basic information on the toxicity of many of the most commonly encountered and toxicologically significant industrial chemicals is provided in Table IV–41. The table is intended to expedite the recognition of potentially hazardous exposure situations and therefore provides information such as vapor pressures, warning properties, physical appearance, occupational exposure standards and guidelines, and hazard classification codes, which may also be useful in the assessment of an exposure situation. Table IV–4 is divided into three sections: health hazards, exposure guidelines, and comments. To use the table correctly, it is important to understand the scope and limitations of the information it provides.
The chemicals included in Table IV–4 were selected on the basis of the following criteria: (1) toxic potential, (2) prevalence of use, (3) public health concern, and (4) availability of adequate toxicologic, regulatory, and physical and chemical property information. Several governmental and industrial lists of "hazardous chemicals" were used. Chemicals have been omitted in cases where little to no toxicologic information could be found, when there are no regulatory standards, or when chemicals have very limited use. Chemicals that were of specific interest, those with existing exposure recommendations, and those of frequent use (even if of low toxicity) generally were included.
Health hazard information. The health hazards section of Table IV–4 focuses primarily on the basic hazards associated with possible inhalation of or skin exposure to chemicals in a workplace. It is based predominantly on the extant occupational health literature. Much of our understanding of the potential effects of chemicals on human health is derived from occupational exposures, the levels of which are typically many times greater than those of environmental exposures. Moreover, the information in Table IV–4 emphasizes acute health effects. Much more is known about the acute effects of chemicals on human health than about their chronic effects. The rapid onset of symptoms after exposure makes the causal association more readily apparent for acute health effects. Nonetheless, the table entries are also informed by nonoccupational human exposure data when relevant (eg, from outbreaks of consumer product exposures) and from experimental animal toxicology. The latter is critical to carcinogenesis assessment, a major chronic exposure endpoint in contradistinction to the acute exposure effects noted earlier.
The table is not a comprehensive source of the toxicology and medical information needed to manage a severely symptomatic or poisoned patient. Medical management information and advice for specific poisonings, where applicable, are found in Section I (see "Emergency Evaluation and Treatment" and "Decontamination") and Section II (see "Caustic and Corrosive Agents"; "Gases, Irritant" and "Hydrocarbons").
Hydrocarbons, which are defined broadly as chemicals containing carbon and hydrogen, make up the majority of substances in Table IV–4. Hydrocarbons have a wide range of chemical structures and, not surprisingly, a variety of toxic effects. There are a few common features of hydrocarbon exposure, and the reader is directed to ...