Common toxic industrial chemicals physical

Appendix A Physical Characteristics of Common Toxic Industrial Chemicals... 

The lanthanide series of metals includes the 15 elements with atomic numbers 57-71, plus yttrium (atomic number 39). The lanthanides occur in the earth s crust at concentrations exceeding some commonly used industrial elements making the term rare earths something of a misnomer. For example, yttrium, cerium, lanthanum, and neodymium are present in the earth s crust at higher concentrations than lead. Of the 15 lanthanides, only promethium does not occur in nature - it is a man-made element. All of the lanthanides have similar physical and chemical properties. Because of similarities in their chemistry and toxicity, the characteristics of the lanthanides are often described as a group. Within the lanthanide group, however, there are differences between the toxicity of the individual lanthanide elements and their compounds. 

Basic information on the toxicity of many of the most commonly encountered and tox-icologically significant industrial chemicals is provided in Table IV-4. The table Is Intended to expedite the recognition of potentially hazardous exposure situations and therefore provides infomiation 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 3 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. 

Recently it has become apparent that many common laboratory chemicals have subtle biological effects that were not suspected previously. A list of 400 toxic substances is available in the Federal Register, Vol. 40, No. 23072, May 28, 1975, and an abbreviated version of this list is presented in Inorganic Syntheses, Vol. 18, p. xv, 1978. For a current assessment of the hazards of any particular chemical, see the most recent edition of Threshold Limit Values for Chemical Substances and Physical Agents in the Workroom Environment published by the American Conference of Governmental Industrial Hygienists. 

Compared with the almost limitless number of chemical compounds that exist or can be formed, the number of chemical propellants in common use is relatively few. This situation arises from criteria including costs, source availability, toxicity, resistance to shock, and other requirements imposed by the vehicle application and the propulsion system design. Another practical reason is that extensive overlap of physical, chemical, and economic properties are displayed by many of the theoretically possible propellants. During the 1960s, the universities, industry, and government in the United States pursued extensive research programs for synthesizing new chemical compounds viewed as candidate propellants,... 

Note also that synonyms for each chemical are common shipping or industry names. Brand or company product names are not given. The reader should careMly examine product material safety data sheets to identify ingredients or specific components that are potentially active or toxic, and then identify the chemical ingredients in the accompanying table. The reader should also refer to the data provided in Chapter S on physical and chemical properties. Data in Chapter S also provides additional information on fire conditions such as latent heats of vaporization, heats of combustion, and heats of decomposition. The last two subsections in this chapter provide further information. 

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