A method for the microdetermination of trichloro-compounds excreted in the urine of workers exposed to trichloroethylene (TCE) was developed. The glucuronide of trichloroethanol was hydrolyzed enzymatically to trichloroethanol, which was then treated with pyridine and potassium hydroxide. The product was treated with p-chloroaniline. The absorbance of the stable-colored product was read in a spectrophotometer at 500 nm. Trichloroacetic acid (TCA) was assayed similarly by omitting the enzymatic hydrolysis. Absorbance obtained by the present method for TCE or TCA was approximately 3 times as much as that obtained by the alkalipyridine method. The use of toxic and carcino-genic chromium oxide was avoided in the present method. In order to investigate the relationship between the trichloroethylene concentra-tion in the working environments and the metabolite concentrations in the urine, surveys were made at several workshops in automobile parts factories. Urine samples collected from workers were analyzed for TCA, TCE and total trichloro-compounds (TTC). The urinary levels of TCA, TCE and TTC were proportional to the environmental concentration of tricholoroethylene. The urinary concentrations corresponding to 50 ppm (TLV) of triehloroethylene were : TCA, 136 ; TCE, 202 ; and TTC, 338 mg/g of creatinine.
Over 300 solvent workers (exposed to either benzene, toluene or the mixture) and about 130 non-exposed workers were examined for subjective symptoms, hematology, and serum and urine biochemistry. The mean time-weighted average exposure intensity was 33 and 59 ppm for benzene workers (for men and women, respectively), 46 and 41 ppm for toluene workers, and 14 ppm benzene + 18 ppm toluene and 18 ppm benzene +21 ppm toluene for mixture workers. The hematology was essentially normal except for marginal findings on WBC counts. Serum and urine biochemistry was not remarkable. The prevalence of subjective symptoms e.g. sore throat, headache and probably dizziness was dose-dependently elevated both in the benzene and toluene groups, whereas that of pancytopenia-related symptoms like gingival bleeding was not related to the intensity of benzene exposure.
Effect of intraveneous injection of beryllium nitrate to adult femalealbino rats primed with Liv-52 and to non-primed rats has been studied on hae-matological parameters after 2, 10 and 30 days of beryllium injection. There was a significant decrease in RBC count, Hb%, neutrophils, blood sugar, alkaline phosphatase, globulin and total protein values with the administration of beryllium nitrate per se whereas, the level of acid phosphatase, cholesterol, totalleucocytes and lymphocytes showed increased values. All the altered values except alkaline phosphatase tend to be normal after the treatment with an Ayurvedic medicine, Liv-52.
Cadmium acetate (Cd2+, 0.4 mg/kg) administration to growing rats (45 ± 5 g), intraperitoneally, daily for 30 days was found to decrease the reduced glutathione (GSH) and increase oxidized glutathione (GSSG) concentrations in liver, kidney and testis. These alterations resulted into a significant decline in GSH/ GSSG ratio in all the three tissues. The observed higher magnitude of changes in testicular tissue are of significance as testis has been reported to be a highly sensitive organ towards Cd exposure. The GSH/GSSG ratio is particularly important for testis, which has a high mitotic index, in view of GSH involvement in the DNA, RNA and protein synthesis. A simultaneous inhibition in the activities of glutathione reductase and glucose-6-phosphate dehydrogenase in these tissues may be responsible for an altered GSH/GSSG ratio as these enzymes take part in GSSG to GSH conversion. The data show that Cd2+ alters glutathione metabolism in various organs which may play a significant role in themechanism of Cd toxicity.
It is well khown that welding arcs emit intense ultraviolet radiation and those who conduct welding operations or work nearby are exposed to the radiation and often suffer injuries. It is desirable to evaluate the ultraviolet radiation from the viewpoint of industrial health. But, there have been few quantitative studies of this radiation. We determined the ultraviolet effective irradiance, based approximately on the recommendation of the American Conference of Governmental Industrial Hygienists, for 14 different arc-welding operations commonly conducted in the workplaces. For most of them, the ultraviolet effective irradiance was at a hazardous level for both those who conduct welding operations and those who work near it. In comparing those welding operations, we found that the ultraviolet radiation hazards vary widely with welding operations. They increase with the diameter of wire, arc current and arc voltage when the type of welding method and the chemical composition of the welding materials are the same.