Acid gases exposure

Health Hazards - Personal Protective Equipment Full face mask and acid gas canister self-contained breathing apparatus chemical goggles mbber apron and gloves acid-proof clothing safety shower Symptoms Following Exposure Severely irritating to nose and upper respiratory tract lung injury Treatment for Exposure INHALATION immediately remove patient to fir h air, keep him warm and... 

Caution. Chalcogenophenols have an unpleasant odor and are toxic. H2S, H2Se, or H2Te may be liberated on treatment with acid or exposure to the open air. These compounds should therefore be handled under inert gas in a well-ventilated hood. Contaminated glassware should be treated with sodium hypochlorite (bleach) solution for several hours and rinsed thoroughly with water and acetone before removal from the fume hood. Mercury and mercury salts are highly toxic, and skin and eye contact must be avoided. Mercury residues should be disposed of as toxic heavy metal waste. 

Detoxification procedures from mustard gas are difficult because of its insolubility and also because of the drastic effects it can have on lung epithelial tissue following inhalation. During World War I, physicians had no curative means of treating the victims of mustard gas exposure. The only method of detoxification that was known involved a rather extreme oxidation procedure using superchlorinated bleaches, such as 5% sodium hypochlorite. Today, several novel methods of detoxification have been developed to counter the effects of mustard gas and these include the use of sulphur-amine solutions and magnesium monoperoxyphthalate. The most effective method to date employs peroxy acids, because they are able to react quickly with the mustard gas. 

Mustard gas exposure also causes inflammatory lung diseases, including acute respiratory distress syndrome (ARDS) (Calvet et al., 1994 Sohrabpour, 1984). A defective secretion of surfactant by alveolar type 11 cells has been implicated as one of the causative factors for the development of ARDS (Ansceschi, 1989). A major component of lung surfactant is DPPC (Stith and Das, 1982). The precursor of DPPC is normally l-pahnitoyl-2-oleolyl PC. DPPC is produced by deacylation and subsequent reacylation with palmitic acid at 2-position of glycerol moiety of the unsaturated phospholipid. 

Nylon fabric was also exposed in darkness to the same temperature, humidity and acid conditions described above. The fabrics were placed in an Atlas Gas Exposure Cabinet model GE-IRC. Filtered air was allowed to flow through the cabinet. For each treatment, fabrics were exposed to light and darkness simultaneously to insure equal amounts of exposure. Following exposure, all fabrics were rinsed in distilled water, neutralized in 1.0% sodium carbonate, rinsed again in distilled water and air dried. The fabrics were then stored at 21 + 1 C and 65 + 1% R.H. for at least 24 hours. 

Carbonic acid gas is absorbed by water, particularly under increased pressure, and gives to that liquid an acidulous taste and the power of reddening litmus although, on exposure to the air, or on boiling, the gas is given off, and the blue colour is restored. With the bases, it unites, forming salts, which are called carbonates but in tne soluble carbonates the alkali is not neutralised, and many carbonates of the base, especially of ammonia, may be obtained, in all of which the properties of the alkali predominate. It would. appear from this, that car-... 

C. Decontamination (see p 46). Rescuers should wear self-contained breathing apparatus, and it there is the potential tor high-level gas exposure or exposure to liquid nitric acid, chemical-protective clothing. 

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