Trichloroethylene exposure in vapour degreasing and the urinary excretion of N-acetyl-beta-D-glucosaminidase.

In order to elucidate the potential nephrotoxicity of low level occupational exposure to trichloroethylene (TRI), urine analysis of the tubular enzyme N-acetyl-beta-D-glucosaminidase (U-NAG) was included in a cross-sectional study of metal degreasers in central Sweden. Eighty-six percent of 8-h TRI in air measurements were well below 50 mg/m3. Normal levels of NAG were found in morning urine samples from 29 workers compared to a historical reference group. A weak positive correlation (r = 0.48; P < 0.01) was observed between U-NAG activity and the concentration of the TRI metabolite trichloroacetic acid in urine but not with other estimates of recent or long-term exposure. In conclusion, TRI does not seem to be nephrotoxic at low exposure levels.

Assessment of intermittent trichloroethylene exposure in vapor degreasing.

To validate various sampling strategies in assessment of trichloroethylene (TCE) exposure, urine and air samples were obtained from 29 metal workers involved in vapor degreasing. Urinary trichloroacetic acid and trichloroethanol were useful metabolites to estimate TCE exposure on a group basis, but the predictive value of a single urine sample was low when related to the air concentration. With intermittent TCE exposure, the best information is obtained by analyzing both metabolites.

Atopic allergy to chloramine-T and the demonstration of specific IgE antibodies by the radioallergosorbent test.

Chloramine-T is a small molecular oxidizing agent that has been widely used as a disinfectant since the beginning of this century. It is generally used in a 5% solution but it is also supplied in powder form. Sporadic case reports of immediate-type sensitization to this agent associated with symptoms of asthma, rhinitis and urticaria have appeared during recent decades. In one of the reports, specific IgE antibodies in sera of four patients who developed asthmatic symptoms after exposure to chloramine-T were demonstrated using a radioimmuno-assay. Three cases of bronchial asthma in workers who had handled chloramine-T powder are described in the present report. Positive skin-prick test reactions to chloramine-T were observed and specific IgE antibodies to human serum albumin treated with chloramine-T were detected using the classic radioallergosorbent (RAST) technique in all three patients.

Diazo-positive metabolites in urine from workers exposed to aromatic nitro-amino compounds.

The amount of diazo-positive compounds in urine from workers at a chemical plant producing pharmaceuticals and explosives was determined in samples collected after work and after a holiday. Forty-five persons working with aromatic nitro-amino compounds (ANA) showed a statistically significant (p less than 0.01) increase in the exposed samples (1.21 +/- 1.40 mmol/mol creatinine) compared to the unexposed samples (0.56 +/- 0.31 mmol/mol creatinine). No increase in the level of diazo-positive metabolites was found in the 25 workers not exposed to ANA compounds. In a follow-up study, 32 trinitrotoluene (TNT) workers were divided into three exposure categories and seemed to show a dose-dependent increase in the level of urinary diazo-positive metabolites. However, there was a considerable interindividual variation. The method seems suitable for the biological assessment of exposure to ANA compounds--at least on a group level. This may be valuable, especially in situations where significant dermal uptake is expected.