Document ZJbyy5q6kZV5GpGzNXwDKYV0J

INDUSTRIAL HYGIENE The effect of some metals, such as mag nesium and zinc, appears to be transient Only limited data are available on the exotic and rare earth metals Although the dusts and fumes from metals with low toxicity do not need as much atten tion as the dusts and fumes from highly toxic metals, they should not be neglected or disregarded The metals with low toxicity are more readily controlled because greater amounts can be tolerated, but their dusts and fumes should be kept at reasonable levels since excessive amounts of any of them can be harmful Inhalation of the dust of lead compounds is the most common mode of entry of lead mto the system, and ingestion of lead com pounds can add to the problem if personal hygiene is poor Workers therefore should be encouraged to wash thoroughly before eat ing, and lunchrooms should be apart from work areas Lead is a normal constituent of plants and animals, and people ingest and excrete it daily even though they are not exposed to lead in their daily work When intake rates exceed the normal excretion rates, however, lead bmlds up m the body When the accu mulation readies a sufficient level, symptoms of poisoning or intoxication appear The concentration of airborne lead should there fore be kept below the threshold limit be cause of lead's high toxicity and its tendency to accumulate in the human system Beryllium intoxication is a severe system ic disease that can result from the inhalation of the dust or fume of metallic beryllium, beryllium oxide, and soluble beryllium com pounds (There is no evidence of intoxica tion from the ingestion of insoluble com pounds ) Only the inhalation of the beryl lium-bearing dusts or fumes produces sys temic disease Accordingly, control of such dusts and fumes to keep them below the concentration specified by ACGIH (Ameri can Conference of Governmental Industrial Hygienists) threshold limit values is a basic protective measure When the soluble salts of beryllium, espe cially beryllium flounde, contact cuts or abrasions on the skin, deep ulcers may be formed which heal very slowly, and com plete surgical excision of the ulcer is some times required to effect healing. Metal fume fever is an acute condition caused by a bnef high exposure to the fresh ly generated fumes of metals such as zinc, magnesium or their oxides Symptoms ap pear from 4 to 12 hr after exposure and consist of fever and shaking chills There is complete recovery usually within one day, and ordinarily the employee can return to the same job without recurrence However, after a period m which there has been no contact with the fume, for example, after a layoff, resumption of exposure is likely to bring on an attack Metal fume fever is caused by heavy con centrations of fumes Zinc oxide fume is the most common source, but cases caused by the inhalation of fumes from magnesium oxide, copper oxide, and other metallic ox ides have also been reported The condition does not occur from the handling of these oxides in powder form Apparently, it re sults only from the inhalation of extremely fine particles freshly formed as fume (called a "nascent fume"). Cadmium, mercury, and other metals may also produce a fever fol lowed by the toxic effects of the element Organic Solvents The widespread industrial use of organic solvents presents a major problem to the in dustrial hygienist the safety engineer, and others charged with the responsibility for maintaining a safe, healthful working en vironment Cettmg the job done without hazard to employees or property is depend ent upon the proper selection, application, handling and control of solvents and an un derstanding of their properties Labeling The labeling of solvents to indicate their properties and health and fire hazards is an extremely Important method for recognizing and evaluating the hazards In fact, if a sol vent is not property labeled, it should not be used The purchasing department can great ly help the safety department by notifying suppliers that only properly labeled solvents will be accepted in the plant Uniformity in language and layout is de sirable to simplify understanding of solvent use The MCA's Guide to Precautionary Labeling of Hazardous Chemicals, Manual L-I. recommends the following subject mat. "Manufacturing Chemists Assn, 1825 Connecticut Ave. NW., Washington, D C. 39-9