Sangyo igaku. Japanese journal of industrial health最新文献

With the revision made to the Regulation on the Prevention of Organic Solvent Poisoning in June 30, 1989, analysis of urine must be made for metabolites as a part of the health examination of workers exposed to xylene, N,N-dimethylformamide, styrene, 1,1,1-trichloroethane, tetrachloroethylene, trichloroethylene, toluene, and n-hexane. In accordance with this Regulation, health examinations were conducted at eight factories of five chemical manufactures in 1990. This report presents the results obtained for 1,073 workers as compiled by the Committee of Industrial Health of the Japan Urea and Ammonium Sulfate Industry Association. 1) The results of data analysis have shown that workers whose urine was collected when they had been exposed to an imperceptible degree to organic solvent or who underwent urine collection during an unknown period of time after exposure numbered 615 or 57.3% of all the workers. 2) Workers whose urine was collected within about 5 hours after exposure numbered 458 (42.7%). The metabolite concentrations in these workers were significantly lower than the BEI values. 3) It may be concluded from the results that workers were exposed to organic solvents to an extremely small extent during organic solvent handling operations at chemical industry factories which maintain good control over toxic materials.

The medical examination of workers exposed to lead was conducted as part of the activity of the Occupational Safety and Health Center (OSHC) Project in the Philippines (JICA Project). The subjects of the medical examination were 21 male and 193 female workers of a semi-conductor plant (abbreviated A company), 59 male and 6 female workers of a refrigerator manufacture (B company); 199 male workers of a storage battery manufacturer (C company); and 107 male and 6 female workers of a lead smelter (D company). Among the examination items were questions regarding occupational history, subjective complaints and objective signs, determination of blood lead levels, urine delta aminolevulinic acid levels, and examination for anemia. The survey was conducted from June to September in 1990. The following results were obtained: 1) The mean age of the workers ranged from 21.8 to 33.8 years. Those of companies A and B were younger than those of companies C and D. The mean employment duration of males at C company was 10.7 yr, and the longest among the four companies. That in both sexes for A company was 1.8 yr and the shortest among the above mentioned companies. 2) The blood lead geometric mean levels of companies C and D showed the highest concentration. The level in males of C company was 64.5 micrograms/dl and that of D company was 80.8 micrograms/dl. The level in females of A company was 9.9 micrograms/dl and the lowest in concentration. The urine delta aminolevulinic acid geometric mean levels were less than 6.0 mg/l in the four companies. There was no company having hemoglobin mean values less than 14.0 g/dl in males or less than 12.0 g/dl in females. 3) The proportion of blood lead levels of 60 micrograms/dl or more was 67.3% in males of C company, and 89.7% in males and 16.7% in females of D company. The proportion of urine delta aminolevulinic acid levels of 6 mg/l or more was 1.0% in females of A company, 20.1% in males of C company, and 43.0% in males of D company. The proportion of hemoglobin values less than 14.0 g/dl in males or less than 12.0 g/dl in females was 4.7% in females of A company, 1.7% in males of B company, 3.5% in males of C company, and 12.1% in males of D company.(ABSTRACT TRUNCATED AT 400 WORDS)

We improved the method for determining urinary delta-aminolevulinic acid (ALA) by HPLC-fluorometer after pre-column derivatization with acetylacetone and formaldehyde, and a stable ALA derivative was obtained without any effect from various urinary components as demonstrated by the complete recovery of ALA (100.9 +/- 5.5%, n = 85) from the urine samples. The modified procedure was as follows: Twenty microliters of urine sample, 5 ml of acetylacetone solution (acetylacetone/ethanol/distilled water containing 4 milligrams of NaCl; 15/10/75), and 0.45 ml of 9.3% formaldehyde solution were mixed and boiled for 15 min. The fluorescent derivative of ALA was separated and analyzed by HPLC with the fluorometer at Ex 246 nm and Em 458 nm. Using a gradient program, the retention time of the ALA derivative was 7.3 min and the analysis could be repeated at 13 min intervals. Concentrations of ALA in urine samples measured by this method were significantly correlated with those measured by the Mauzerall-Granick (M-G) method (n = 85, r = 0.993, p < 0.001). The values obtained by our method were, however, lower than those obtained by the M-G method. Urinary ALA concentrations of 40 non-lead workers ranged from 0.1 to 2.3 mg/g creatinine with the mean +/- SD of 1.1 +/- 0.4 mg/g creatinine as measured by the present method.

To date the evaluation of chemically-induced neurotoxic effects on humans has been dependent mostly on electrophysiological measurements, neurobehavioral tests and biological exposure assessment. However, recently attempts have been made to develop biochemical parameters in peripheral body fluids which can be easily obtained from humans and which can represent markers for the same parameters in nervous tissue. The approach of this kind is logically based on the following facts: 1) Blood cells (e.g., platelets and lymphocytes) possess some characteristics of monoaminergic neurons such as the existence of storage vesicles of monoamines, membrane neurotransmitter receptors, high affinity uptake sites and neurotransmitter-related metabolizing enzymes. 2) Leakage of nerve-specific markers from nervous tissue to peripheral body fluids may occur following damages of target neuronal cells or macromolecules. 3) Quantitative and/or qualitative alterations of peripheral biochemical markers (e.g. neurotransmitter receptors) can be induced by the regulation mechanisms of neuronal, endocrinal and immunologic interactions when the nervous functions are perturbed by various exogenous or endogenous factors. Erythrocyte acetyl cholinesterase (AChE), free erythrocyte protoporphyrin (FEP), lymphocyte neurotoxicity target enzyme (NTE), blood aminolevulinic acid dehydratase (ALA-D), and carboxyhemoglobin (CO-Hb) are well-known peripheral markers of the effects induced by organophosphates (AChE, NTE), lead (FEP, ALA-D) and carbon monoxide (CO-Hb). Many studies have been made on the effects of organic solvents, heavy metals and pesticides on neurotransmission parameters in blood cells such as neurotransmitter uptake, receptor binding and enzyme activity. This paper summarizes the present knowledge on the development and clinical applications of some peripheral biochemical markers such as neurotransmission parameters in blood cells and neuronal or glial cell marker proteins in CSF, blood and urine. The role of these peripheral biochemical markers in the assessment of environmental chemically-induced human neurotoxicity is also discussed.

The effects of Breslow's seven health practices on health were examined. The Today Health Index (THI), a questionnaire for self-evaluation of physical and mental health, was applied to male workers of a private company as well as their wives. The subjects resided in the suburbs of Tokyo and the average ages of the males and females were 41.5 and 38.4 years, respectively. Statistical results were obtained using Mann-Whitney U-test, analysis of covariance, and Hayashi's quantification theory I. A statistically significant decrease in the THI scale scores among subjects observing six or more health practices when compared with those observing three or less was demonstrated in vague complaints and irritability in males, and in respiration in females. In males, the THI scale scores of vague complaints, respiration, and the mouth and anus significantly decreased by sleeping well. Those of irritability and irregularity of life decreased by not smoking and those of vague complaints and irritability decreased by not eating between meals. In females, the THI scale scores of vague complaints, eye and skin, and the mouth and anus significantly decreased by exercising regularly. Those of irregularity of life decreased by not smoking. Those of respiration decreased by good weight control. Those of respiration and the mouth and anus decreased by not eating between meals. Exercising regularly in females was a good predictor of vague complaints using multi-variate analysis adjusted for age. Subjective evaluation of health improved by Breslow's recommended health practices.