Document Q6YON78nNDJnNmNGX7mjzgJ7

38--Industrial Toxicology Ethyl silicate (ethyl orthosilicate) is a mod erately volatile liquid used as a waterproofing and weatherproofing agent for masonry and ceramic objects It has a sharp odor and is irritating to the eyes, nose, and throat at high concentrations In animal experiments it has produced lung and kidney injury as its mam toxic effects F Fluorides in the form of the soluble in organic salts which can hydrolyze to form free hydrogen fluoride in contact with the tissue are severely irritating, and many of them can produce skin bums which are both extensive and painful The less soluble in organic salts are not irritating but may pro duce a type of chronic poisoning by longcontinued inhalation The fluoride ion tends to accumulate m the skeleton Softening of the bone has been considerably more of a problem with cattle exposed to fluorides than it has been with people so exposed According to one investigation, the use of welding rods with fluondes m the coating does not introduce a hazardous amount of fluonde into the general air of the welding shop Un der the welders helmet, the concentration varied widely For limits of fluonde concen trations m drinking water, see Table 20-B m Chapter 20, 'Industrial Sanitation and Person nel Facilities " Fluorine is a yellow, highly reactive gas that combines with water or moisture m the air to form hydrogen fluonde, and, possibly oxygen fluonde, which is more toxic than fluonne Fluorine's health hazard is designated as extra hazardous for acute exposure and high for chronic exposure Too few industnal exposures to fluonne have been evaluated to recommend specific first aid procedures However, removal of the victim from the contaminated area and ad ministration of 100 percent oxygen to relieve respiratory distress are advisable Fluorotnchloromethane (tnchloi omonofluoromethane, Refngerant-11) has about the same toxicity as dichlorodifluoromethane Formaldehyde is a colorless pungent gas, usually furnished as a solution containing 37 1146 percent by weight of formaldehyde and a small quantity of methyl alcohol as a preserva tive Both the gas and this solution (forma lin) have a pronounced lmtant effect upon the skin Prolonged contact with dilute formalin will cause the fingernails to become scaly and brittle and the nail matrix to become thick and inflamed Formaldehyde gas is extremely irritating to the respiratory system in concentrations of 50 ppm in air If the concentration is high, the gas may penetrate to the lungs and produce bronchial inflammation and edema, likely fol lowed by pneumonia Contact of liquid formaldehyde or formalin with the skin can be largely prevented by pro tective clothing and by water insoluble pro tective creams Splashes of the liquid should be washed off immediately Breathing of the vapor should be prevented by enclosure and ventilation of processes Formic acid is commonly shipped as a con centrated 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 substances The acid is irritating to the skin, forming blisters which continue to spread even after the acid has been removed from the skin-- an effect similar to that produced by ant and bee venom, which contain formic acid Furfural. The irritating properties of fur fural, which become uncomfortable at 20 to 50 ppm, probably preclude voluntary ex posures which might lead to significant injury The information presented in the literature is conflicting regarding the toxicity of furfural vapor One report concludes that the physio logic effects of the vapor were relatively mild and similar to that of butyl alcohol Another report describes numbness of tongue and mucous membranes of the mouth, absence of taste sense, and difficulties in breathing which were experienced m workers in a furfural plant where there was inadequate ventilation In a more recent report it was stated that in re fining operations and in the synthetic resin industry (where large amounts of furfural have been used), only occasional rejiorts of individual sensitivity were observed