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Peculiarities of nervous system functional state in electric welders exposed to manganese compounds. To evaluate nervous system functional state in electric welders exposed to manganese compounds, the authors conducted transverse study with matched pairs. The electric welders' tests for response rate, diadochokinesis and grasping power were not reliable. No changes were found in tremor characteristics and posture steadiness. Bradykinesia appeared to prevail in welders.

Objective: To study possible cross shift effects of environmental tobacco smoke (ETS) on pulmonary function among bar and restaurant employees before and after the implementation of a smoking ban in Norway., Methods: The study included 93 subjects employed in 13 different establishments in Oslo. They were examined at the beginning and end of a workshift both while ETS exposure was present and when smoking was banned. The mean exposure level of nicotine and total dust before the ban was 28 microg/m3 (range 3-65) and 275 microg/m3 (range 81-506), respectively. Following the smoking ban, the mean level of nicotine and total dust was 0.6 mug/m3 and 77 microg/m3, respectively. Assessment of lung function included dynamic lung volumes and flows., Results: The cross shift reduction in forced vital capacity (FVC) among 69 subjects participating in both examinations changed from 81 ml (SD 136) during exposure to ETS to 52 ml (SD 156) (p = 0.24) following the smoking ban. The reduction in forced expired volume in one second (FEV1) during a workshift, was borderline significantly reduced when comparing the situation before and after the intervention, by 89 ml (SD = 132) compared to 46 ml (SD = 152) (p = 0.09), respectively. The reduction in forced mid-expiratory flow rate (FEF25-75%) changed significantly from 199 ml/s (SD = 372) to 64 ml/s (SD = 307) (p = 0.01). Among 26 non-smokers and 11 asthmatics, the reduction in FEV1 and FEF25-75% was significantly larger during ETS exposure compared to after the smoking ban. There was an association between the dust concentration and decrease in FEF25-75% before the ban among non-smokers (p = 0.048)., Conclusions: This first study of cross shift changes before and after the implementation of a smoking ban in restaurants and bars shows a larger cross shift decrease in lung function before compared with after the implementation of the ban.

Chromosome aberrations and micronuclei in peripheral lymphocytes were studied in 29 male chloralkali workers previously exposed to mercury vapor and in two matched reference groups comprising 29 nitrate fertilizer workers and 29 customs and police officers. The study was performed using whole-blood cultures with and without hydroxyurea and caffeine to inhibit deoxyribonucleic acid synthesis and repair, respectively. No significant differences in the frequencies of chromosome aberrations and micronuclei were observed. However, a nonsignificant increase in chromosome breaks and dicentrics was found in the subgroups with high urinary mercury peak levels or high cumulative mercury exposure. An increased prevalence of "high" scores of chromatid breaks in the inhibited cultures, exceeding the 75th percentile of all of the subjects studied, was observed for the chloralkali workers when compared with both reference groups. No evident cytogenetic effects were observed among the chloralkali workers with the methods used in the present study.

Urinary albumin concentration (U-alb) and N-acetyl-beta-D-glucosaminidase (U-NAG) and glomerular basement membrane antibodies (a-GBMs) in serum samples were measured in 77 chloralkali workers previously exposed to mercury (Hg) vapour and 53 age matched referents. The exposure ceased on average 12.3 (range 1-35) years before the study. The mean exposure time was 7.9 (range 1.1-36.2) years. The mean yearly urinary Hg concentration (U-Hg) was 531 nmol/l. The concentrations of the urinary isoenzymes NAG A (U-NAG A) and NAG B (U-NAG B) were determined in 30 highly exposed subjects and 30 referents. No differences in U-alb or U-NAG, U-NAG A, or U-NAG B were found between the groups. Higher concentrations of a-GBMs were found among subjects who stopped exposure a short time before the study, but there was no association between a-GBMs and U-alb. The U-NAG and U-NAG A were negatively correlated with storage time. The results may suggest that microalbuminuria and enzymuria reported in subjects with ongoing exposure to Hg vapour are reversible in most instances.

Seventeen former chloralkali workers were followed through the regular determination of urinary mercury for nearly two years after the cessation of exposure to mercury vapor in a study of the time course of urinary mercury elimination. Their duration of exposure ranged from 3 d to 35.5 years. A one-compartment model for urinary mercury elimination was applied. The urinary mercury concentration declined at a rate indicating a half-time of 91 d. When corrected for an individual base-line level of urinary mercury resulting from sources of mercury intake not related to work, the half-time was 72.4 [95% confidence interval (95% CI) 63.2-81.7] d, with a mean elimination rate constant of 0.011 (95% CI 0.008-0.013).d-1. The day-to-day variability of the urinary mercury concentration averaged 22%, expressed as the coefficient of variation between urine samples delivered on three consecutive days.

A cross sectional study of aspects of their neurology was carried out on 77 chloralkali workers previously exposed to mercury (Hg) vapour and compared with 53 age matched referents. The chloralkali workers had been exposed for an average of 7.9 years at a concentration of 59 micrograms Hg/m3 in the working atmosphere. The individual mean urinary concentration of Hg for each year of exposure was 531 nmol Hg/1. On average the exposure had ceased 12.3 years before the examinations. Both the median sensory nerve conduction velocity and the amplitude of the sural nerve were associated with measures of cumulative exposure to Hg. An association was also found between years since first exposure to Hg and aspects of the visual evoked response. Previously exposed subjects with postural tremor or impaired coordination also had alterations in visual evoked response. These results may indicate an effect of previous exposure to mercury vapour on the nervous system, possibly in the visual pathway, cerebellum, and the peripheral sensory nerves.

The aim of this study was to investigate the relationship between organic solvent exposure and brain atrophy among 85 patients referred to a department of occupational medicine and who underwent cerebral computed tomography. On average, the patients had been heavily exposed to a mixture of organic solvents for 22.9 years. Diseases which may be associated with brain atrophy or high alcohol consumption was observed among 31% of the subjects. Among these subjects the prevalence of brain atrophy was 58%. The prevalence of brain atrophy was 20% among the men without such conditions. None of the eight female patients appeared to have atrophy. The quantitative assessment showed no correlation between the duration of exposure and atrophy-related parameters. However, the width of the third ventricle, bifrontal ratio, and bicaudate ratio were correlated with age.