An environmental and a health survey of two diesel bus garages in Alexandria (Egypt) have shown an air pollution problem due to the exhaust of engines containing SO2, NO2, aldehydes and hydrocarbons within permissible levels and a relatively higher concentration of smoke. The examination of workers revealed the occurrence of upper respiratory tract disease, chronic bronchitis, asthma, peptic ulcer, gastritis and high blood pressure in prevalences higher than expected. Respiratory diseases were probably due to a synergistic effect of smoke and irritants as well as the presence of acrolein and adsorbed hydrocarbons and the smoking habits of workers. Cases of chronic dyspepsia and peptic ulcers were probably related to the nervous tension of night shifts, and other factors as the irregularity of meals and the probable swallowing of dissolved irritants. The blood pressure was relatively "higher" among night shift workers. Although air pollution could physically be within permissible levels for its individual components, a prolonged exposure associated with synergism of different irritants and smoking may lead to actual pathological damage. Night shifts are considered a stress of considerable effect on health. Psychosomatic disorders could occur particularly if those workers are simultaneously exposed to other physical stresses.
An acute toxicity of phthalodinitrile and tetrachlorophthalodinitrile in mice was investigated. Isomers of the both compounds were examined and significant differences were noticed in their LD50 values as well as in the symptoms of acute intoxications. The respective intraperitoneal LD50 of o-, m-, and p-phthalodinitrile were 34.5, 481.3 and 698.6 mg/kg, and those of o-, m-, and p-tetrachlorophthalodinitrile were 66.4, 2.5 and 1581.3 mg/kg. From the results obtained, it was suggested that these compounds had different toxic properties.
The acid phosphatase activity in the macrophages rapidly increased by the addition of alkali-treated quartz particles, but did not by ground quartz particles. This rapid increase of acid phosphatase activity in the macrophages was also observed by cristobalite, but not by microcline, cyanite, tourmaline and others. β-Glucuronidase, cathepsin and alkaline phosphatase in the macrophages were not activated remarkably by the quartz particles. The activation of acid phosphatase of the cells by quartz particles was prevented by polyvinylpyridine-N-oxide.
Phthalic anhydride reacts with hydroquinone in sulphuric acid, and changes into quinizarin. Phthalodinitrile can be determined as the yellow benzene solution of quinizarin using this reaction. Though this method is very simple, the temperature of reaction and the amount of sulphuric acid or hydroquinone affect the yield of quinizarin delicately. So the conditions of reaction should be controlled severely.
Dynamic adsorption of acetone vapor stream by active carbon column was studied. The breakdown time of the granular active carbon column for acetone stream was observed at 60°C, in relation with the flow rate of the stream, influent acetone vapor pressure and particle size of active carbon. When the flow rate of the stream was varied in the range of 76-20 ml/min., the breakdown time was nearly inversely decreased with the increase of flow rate. The breakdown times for streams of 30 ml/min. containing acetone vapor of 91.0, 69.5, 54.0 and 8.7 mmHg were 16.8, 22.2, 27.0 and 68.5 minutes respectively. The effect of particle size in the range of 28-60 mesh on dynamic adsorption showed that the smaller the particle size of packed carbon, the longer the breakdown time of adsorption, though the packed amount of adsorbent in the column was the same. These results were discussed in comparison with other authors reports.
From practical requirement for gas removing ability of canister for organic gas with methyl bromide, life of the canister was tested and the breakdown times obtained were 32.3 min and 34.5 min at 5 ppm and 20 ppm of effluent gas concentrations, respectively. Sixteen canisters were tested and the mean deviations were 2.1 min and 1.8 min for each breakdown time, respectively. Concentration of influent methyl bromide gas for present test was 0.5% by volume in air stream of 30 1/min at 20°C. Logarithm of effluent gas concentration was approximately linear to contact time of canister with test air stream and the linear relationship coincided with equation derived by Danby et al. Canister used for present test was certified by the pr, oducing company that its breakdown time was 150 min or more when concentration of effluent gas exceeded 5 ppm using carbon tetrachloride as test gas, concentration of which was 0.5% by volume in influent air stream. The ratio of lives of the canisters for those two gases thus was about 1 : 5. Some consideration was done on adsorptibity of adsorbent from properties of intermolecular interaction of gas in adsorption state.