Document G60oQq7N21Lb0w2MeO2Nxdzj4

ELEMENTS OF INDUSTRIAL TOXICOLOGY malm with the skm can be largely prevented by protechve clothing and by water insolu ble protective creams Splashes of the liquid should be washed off immediately. Breath ing of the vapor should be prevented by en closure and ventilation of processes. See Industrial Data Sheet 342 and Hy gienic Guide Formic add is commonly shipped as a concentrated solution in glass carboys. The acid is a strong reducing agent and the vapor is flammable It should not be stored m the immediate vicinity of oxidizing sub stances. The acid is untatmg to the skin, forming blisters which continue to spread even after the add has been removed from the skm-- an effect similar to that produced by ant and bee venom, which contain fonmc acid Gasoline varies in composition, but is commonly a petroleum fraction containing hexanes, heptanes, and octanes with varying amounts of unsaturated, cychc, and aro matic compounds. A cracked gasoline may contain 50 per cent or more of compounds other than the saturated aliphatic hydro carbons. If the gasoline consists of saturated and unsaturated aliphatic compounds and cyclic compounds, it will be a narcotic and an ir ritant to the mucous membranes The mam tone action will be depression of the central nervous system with symptoms of giddiness, dimness, hilarity, and headache not unlike an alcoholic intoxication. Mild symptoms of this sort are apt to be produced by relatively short exposures to concentrations of 500 to 750 ppm of this land of gasoline In addi tion, mdd blood changes, neuritis, and neu rasthenias have been reported If the gasoline is made from a crude oil containing 40 per cent or more of aromatics or is enriched in aromatics by die refining process, the toxicity may be substantially higher The tetraethyl lead content of gasoline is low enough to make any lead exposures from ordinary handling and dispensing of gasoline m garages and filling stations neg ligible. Tetraethyl lead can however pre sent a tone hazard by inhalation and ab solution through tiie skin when entry is made into tanks and other confined spaces that have contained leaded gasoline. See Lead (on page 40-33) and Hygienic Guide Germanium, one of die less common met als which have some industrial uses, is em ployed particularly m the electronics indus try for diodes and transistors. It appears to be a relatively inert metal and has not been reported as the cause of any occupational diseases m man. In animal experiments, the LDa for rats by mtrapentoneal injection was about 750 mg/kg of body weight when germanium oxide was buffered to near the neutral point Food containing 1,000 ppm or water containing 100 ppm was fatal to half of the young rats. Repeated sublethal doses pro duced some tolerance to a subsequent lethal dose, bnt die tolerance declined substantial ly in six weeks Graphite has been repeatedly reported to produce a pneumoconiosis m workers in mines, mills, and electrode plants. Several investigators have done autopsies on men who died from graphite pneumoconiosis and found their lungs to contain fibrous masses with central necrosis, in addition to emphy sema and general fibrosis around the blood vessels and lymph channels. The typical X-ray patterns start with a miliary "snow storm" effect and progress to a pattern of sharply defined masses of various sizes m each lobe Halogenated hydrocarbons--see also the individual compounds--as used in industry are potent anesthetics and more or less toxic. On exposure to high concentrations the most common symptoms are nausea, vomiting, diarrhea, headache, and uncon sciousness If unconsciousness occuis, it may be fol lowed by sudden death due to fibrillation of the heart or respiratory failure, as has fre quently been observed in the medical use of these compounds After exposure to amounts which are large but not sufficient to pro duce sudden death, there may be severe kid ney and liver damage eventually leading to ilpqth. The most common halogenated hydrocar bons, arranged in the order of increasingly acute toxicity, are vinyl chloride, methyl chloride, ethyl chloride, ethylene dichlonde, ethyl bromide, carbon tetrachloride, dichkn- omethnne, methyl chloroform, tnchlorotby- lene, methyl bromide, tetrachloroethylene, pentachlorocthane, and tetrachloroethane. 4034