Persistence of decreased T-helper cell function in industrial workers 20 years after exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin

OBJECTIVE: To evaluate the distribution of mepivacaine hydrochloride after distal interphalangeal (DIP) joint injection in horses. DESIGN: Prospective, uncontrolled study. ANIMALS: 10 adult horses. PROCEDURE: 30 minutes before euthanasia, 8 ml of 2% mepivacaine hydrochloride was injected into the dorsal pouch of a forelimb DIP joint. Synovial tissue from the DIP joint and podotrochlear (navicular) bursa and bone tissue from the medullary cavity of the distal sesamoid (navicular) bone were taken from both forelimbs immediately after death. All synovial and bone specimens were analyzed for tissue concentration of mepivacaine by high-performance liquid chromatography. Synovial tissue and bone specimen concentrations from the injected forelimb were compared with corresponding specimens from the noninjected forelimb. All synovial tissue and bone specimen concentrations were compared with an estimated effective tissue concentration of mepivacaine (0.3 microgram/mg) for local anesthesia. RESULTS: Specimen concentrations of mepivacaine from the injected forelimb were significantly greater (P < 0.05) than those in the corresponding tissues of the contralateral noninjected forelimb. All DIP joint and navicular bursa synovial tissue specimens from the injected forelimb had greater than the estimated effective tissue concentration of mepivacaine for local anesthesia. Of the 10 navicular bone specimens from the injected forelimb, 4 were higher and 2 were within 20% of the estimated effective tissue concentration of mepivacaine for local anesthesia. CONCLUSIONS: Mepivacaine hydrochloride deposited into the DIP joint should anesthetize pain arising from navicular bursa synovia and may decrease pain arising from the medullary cavity of the navicular bone. CLINICAL RELEVANCE: DIP joint injection of mepivacaine hydrochloride is not specific for DIP joint pain.     

Perinatal exposure to morphine: reactive changes in the brain after 6-hydroxydopamine

The decapeptide H2N-Ser-Leu-Thr-Cys-Leu-Val-Lys-Gly-Phe-Tyr-COOH (termed immunorphin) corresponding to the sequence 364-373 of the CH3 domain of the human immunoglobulin G1 Eu heavy chain and displaying a 43% identity with the antigenic determinant of beta-endorphin was synthesized. Immunorphin was found to compete with 125I-beta-endorphin for high-affinity receptors on murine peritoneal macrophages (K = 2.5 +/- 0.9 x 10(-9) M) and with 3H-morphin for receptors on murine thymocytes (Ki = 2.7 +/- 0.6 x 10(-9) M) and murine macrophages (Ki = 5.9 +/- 0.7 x 10(-9) M). In particular two types of receptors to 125I-beta-endorphin with Kd1 = 6.1 +/- 0.6 x 10(-9) M and Kd2 = 3.1 +/- 0.2 x 10(-8) M were revealed on macrophages. The second type of receptors interacted with 125I-beta-endorphin, 3H-Met-enkephalin, 3H-Leu-enkephalin and 3H-morphin; the first displayed reactivity with 125I-beta-endorphin, 3H-morphin and immunorphin. The first type receptors are not present on murine brain cells nor are inhibited by naloxone. A minimum fragment of immunorphin practically completely retaining its inhibitory activity in the competition tests with 125I-beta-endorphin for common receptors on thymocytes was found to correspond to the tetrapeptide H2N-Lys-Gly-Phe-Tyr-COOH (Ki = 5.6 +/- 0.5 x 10(-9) M).     

Lead exposure of workers in the ceramics industry and relevant factors

To clarify lead exposure and factors relevant to it, an occupational health survey and air lead-concentration survey were conducted among 425 workers in the ceramics industry in the Seto region in Aichi Prefecture. As for biological monitoring, blood lead level was measured according to sex, job, product, factory size and duration of lead exposure. The following major findings were obtained in the present analysis. Workers making dolomite novelties showed higher blood lead levels than those making porcelain novelties, semi-porcelain novelties and tableware. The difference in blood lead level by job was statistically significant, but not that by factory size. In males, the highest blood lead level was found for spray painting work (28.7 micrograms/dl), followed by glazing work (28.0 micrograms/dl), kiln work (23.3 micrograms/dl) and painting work (22.3 micrograms/dl). In females, the blood lead level for painting work (13.5 micrograms/dl) was lower than those for glazing work (26.1 micrograms/dl) and kiln work (31.4 micrograms/dl). The blood lead level was significantly increased with the number of years of lead exposure in females (painting work). It was coincidentally clarified that the environmental lead concentration varied according to the job in which workers were engaged. As protective measures against lead exposure for workers in the ceramics industry, the development of nonlead paint and glaze and the introduction of more effective dust collectors at the workplace should be established.     

Follow-up immunogenicity of an inactivated hepatitis A virus vaccine in healthy children: results after 5 years

Long-term persistence of hepatitis A virus (HAV) serum antibody in vaccinated children has not been demonstrated in previous studies. To study the long-term immunogenicity to HAV vaccine, three doses of strain HM 175 HAV vaccine with 360 enzyme-linked immunosorbent assay units were administered to 107 children, aged from 1.0 to 6.8 years, at 0, 1, and 6 months. The administration of one vaccine dose induced seropositivity (anti-HAV titer > or = 20 mIU ml-1) in 95% of all vaccinees at month 1. All subjects remained seropositive until month 6. The titers of HAV antibody remained above 20 mIU ml-1 in all subjects followed up to 60 months. The geometric mean titer (GMT) reached its peak (3802 mIU ml-1) at month 7, i.e. 1 month after the booster dose, and then declined until the end of follow-up at month 60 (661 mIU ml-1). A trend of higher GMT in female subjects persisted up to month 60. The changes of the GMT over time were best described by the regression equation: log (GMT) = 3.26-0.08 x (age in years) (r = -0.95, P = 0.014). According to this equation, the geometric mean concentration would reach 20 mIU ml-1 at around 24.5 years after the beginning of vaccination. In conclusion, those who completed the recommended three-dose inactivated HAV vaccination series remained seroprotective for at least 5 years. Theoretically, such a vaccination program can provide a protective period of over 20 years in children. This paper may be the first to describe at least 5-year immunogenicity of inactivated HAV vaccination in healthy children.     

Variability of respiratory system reactions to air pollutants. Epidemiologic study of children in Cracow

The main purpose of the study was to corroborate the hypothesis that the history of allergic skin reactions is the marker of individual susceptibility of respiratory tract to air pollutants in children. The study has been carried out in two contrast areas of the city regarding the air pollution level. In the dirty area the annual daily mean concentrations of particulate matter was 51.5-74.5 micrograms/m3 and sulfur dioxide 58.4-73.8 micrograms/m3; in the cleaner part of the city the corresponding concentrations were 31.7 and 36.1 micrograms/m3. The medical examination of 171 children covered standardized interviews with mothers and spirometric measurements. The results obtained showed that despite the marked decline in air pollution level, the current level of common air pollutants in the city is hazardous to the health of inhabitants. The children with history of allergic skin reactions have been affected much stronger by the higher level of air pollutants than other children. Beside the higher frequency of chronic cough or phlegm, wheezing or shortness of breath, they had significantly poorer lung function measured by FEVI/FVC index.     

A study on the neurobehavioral effects of occupational exposure to organic solvents in Korean workers

Atomic absorption spectroscopy was used to assess uptake of Ag+1, Au+4, Cd+2, Cu+2, In+3, Ni+2, Pd+2, and Zn+2 by in vitro cultures of Balb/c 3T3 fibroblasts as a function of concentration of the cations in cell-culture medium. Reversibility of this uptake was also measured. Metal cations exhibited a 400-fold difference in their tendency to accumulate in the cells; In+3 tended to accumulate the most, whereas Pd+2 accumulated the least. Uptake of the cations in the cells increased linearly with the concentration of the cation in the medium for all cations up to their 50% toxicity concentrations. Reversal of this uptake was slower than that of the initial uptake for three cations studied in more detail (Cd+2, In+3, and Ni+2). The duration of the initial exposure affected the proportion of the metal cations that were retained by the cells 5 h after the cations were removed from the medium. The proportion of retained Cd+2 did not change when the initial exposure was increased from 2 h to 6 h, whereas the proportion of retained In+3 decreased and Ni+2 increased over the same period. The tendency of the cells to accumulate these cations correlated with their cytotoxic potency (measured previously).     

Follow-up of a cohort of 422 children aged 6 to 13 years conceived by in vitro fertilization

OBJECTIVE: To contact the total cohort of children conceived by IVF-ET consecutively in our center between June 1981 and December 1988. DESIGN: Retrospective study. SETTING: Infertility unit of the department of Obstetrics and Gynecology, Antoine Béclère Hospital, Clamart, France. PATIENT(S): Complete information was obtained on 370 children. The percentage lost for follow-up was 9%. INTERVENTION(S): To assess the children's well-being, telephone interviews of the parents and questionnaires sent to the parents and/or pediatrician were used. MAIN OUTCOME MEASURE(S): Surgical procedures, malformation, height and weight, school performance. RESULT(S): The physical growth of these children showed no major pathological features, with only 2.2% of them being below 2 SD for weight and 0.3% for height. The rates of malformation were not significantly different between these children and the general population. School performance was good, with 92.2% presenting encouraging outcome. Fifty-eight percent of the parents of children aged 6 to 10 years old did not inform their children about the IVF nor did 34% of the parents of children aged 11 to 13. Subsequent to the birth of the IVF child, 30 patients (8.9%) had a spontaneous pregnancy. However, five of them (15.1%) were ectopic. CONCLUSION(S): This study reports, for the first time, reassuring data on the long-term assessment of a large group of older IVF-ET children conceived consecutively, with a low percentage of subjects lost for follow-up.     

Demographic evaluation of the fertility of aluminium industry workers: influence of exposure to heat and static magnetic fields

A demographic analysis of the fertility of French aluminium industry workers was performed in order to evaluate the potential effects on male fertility of occupational exposure to heat and static magnetic fields occurring in certain workshops. Two groups of aluminium workers were studied: one group of 692 potroom workers exposed to heat and to static magnetic fields, and a control group of 588 workers from the same plants, who had not been exposed to these factors. The birthrate was significantly higher in the 'exposed' group than in the 'control' group. The relative birthrate ratio ('exposed' versus 'control') was 1.1 (P < 0.001). These results do not show any decrease in the fertility of potroom workers exposed to heat and static magnetic fields, when compared to other workers in the aluminium producing industry.     

Validity of subjective assessment of changes in respiratory health status: a 30 year epidemiological study of workers in Paris

The validity of scales used for subjective assessment of health, particularly transitional indices, is under discussion. The aim of the present study was to assess the concurrent and predictive validity of a simple estimate of long-term subjective assessment of respiratory health changes. A longitudinal study of 915 workers was conducted over 30 yrs, with both retrospective self-assessment of respiratory health changes and objective measurements of spirometric values 12 yrs apart. An assessment of the reason for death during the subsequent 20 yrs was performed. Subjective assessment of respiratory deterioration over 12 yrs was significantly related to both cross-sectional lung function values and longitudinal lung function changes (forced expiratory volume in one second (FEV1) decline), an association which remained after adjustment for FEV1 level. It was also related to the same risk factors as decline in FEV1 (smoking, occupational exposure). Self-evaluation of respiratory deterioration was significantly predictive of death from all causes, with the highest (but nonsignificant) rate ratio for respiratory causes. Asthmatics exhibited greater long-term variability (objective and subjective) than nonasthmatics. Independent of dyspnoea, self-assessment of respiratory health deterioration was significantly related to FEV1. Subjective assessment of long-term changes in respiratory health provides valid information.     

Hepatologic parameters in health personnel after several years of occupational exposure to anesthetic gases

The aim of this study was to indicate necessity of establishing sensitive methods for early detection of hepatobiliary tract disorders after exposure of medical staff to anesthetic gases, as well as to follow-up working conditions in operating rooms. The examined group comprised the medical staff of the Surgical Department of the Institute of Surgery in Novi Sad. In the group of examinees levels of bilirubin in blood were increased; prevalent increase of the indirect bilirubin occurred too, while she increase of the direct bilirubin concentration was almost insignificant. Alanine aminotransferase concentration was slightly increased in the examined group, while aspartate aminotransferase reacted in much more expressed concentration increase. On the basis of gathered results it can be concluded that there are, for now, slight functional hepatic changes in the exposed workers, which may be the consequence of exposure to anesthetic gases.     

Structural changes in the genital system of nematodes of the suborder Strongylata after exposure to anthelmintics

OBJECTIVE: To assess whether phenylalanine intervention can effectively improve the pre-hypertensive inherited cardiac hypertrophy and systolic dysfunction in young offsprings of patients with essential hypertension (ER). METHODS: Ninty-six normotensive adolescents with hypertensive family history and associated with inherited cardiac hypertrophy, i.e, interventricular, septum (IVST) and (or) left ventricular post wall thickness (PWT) > or = 10.5 mm, were screened according to the normal range criteria of ultrasonic-cardiogram (UCG) obtained previously from 50 normotensive adolescents without hypertensive genetic predisposition. The UCG parameters before and after 3, 6, 9 months of observation were compared between intervention group (Phe 1 g/d 58 subjects) and placebo-control group (placebo 1 g/d, 38 subjects) in 2 separate trials by a double-blind, randomized, cross-over and comparable placebo-control design. RESULTS: The hypertrophy and dilatation of ascending aorta and left heart structure were regressed after intervention, i.g, the changes after 9 months intervention, IVST dropped from 10.9 +/- 1.2 to 9.2 +/- 0.6 mm, PWT from 9.5 +/- 1.0 to 8.6 +/- 0.6 mm, left ventricular mass index from 92 +/- 15 to 70 +/- 11 g/m2; All of the parameters reflecting the systolic function of left ventricle were improved in pooled group of 2 trials. The UCGs after placebo was fundamentally not changed except some sporadic values. The results were similar in 2 separate trials. The improvement after Phe and its return towards that of pre-intervention after stope were remarked at 6 months. CONCLUSION: The inherited cardiac dearrangement seen in adolescents with hypertensive genetic predisposition can be assumed to be the pre-hypertensive changes of EH. It can be reversed by phenylalanine--a natural and essential amino-acid.     

Neurotoxicity in young adults 20 years after childhood exposure to lead: the Bunker Hill experience

OBJECTIVES: An epidemiological study of young adults was conducted to determine whether environmental exposure to lead during childhood was associated with current adverse neurobehavioural effects. METHODS: The exposed group consisted of 281 young adults who had been exposed environmentally to lead as children and the unexposed referent group consisted of 287 age and sex frequency matched subjects. Information on demographics, past and current health, and past exposures to neurotoxicants, and responses to the Swedish Q16 questionnaire were collected by interview. Standard neurobehavioural and neurophysiological tests were administered by computer or trained technicians. K x ray fluorescence was used to estimate tibial bone lead concentrations among the exposed and unexposed groups. Associations were examined between the exposed group and referents and tibial bone lead concentration and the neurobehavioural and neurophysiological outcomes of interest. RESULTS: Among the measures of peripheral nerve function, after controlling for confounders, sural sensory nerve evoked response amplitude, peroneal motor nerve compound motor action potential amplitude, vibrotactile thresholds of fingers and toes, and standing steadiness were significantly associated with exposure group. Among the neurobehavioural tests, hand-eye coordination, simple reaction time latency, trails B latency, symbol digit latency, serial digit, and learning error score were also significantly associated with exposure group after controlling for confounders. Exposed subjects had significantly more neuropsychiatric symptoms than the referents. Associations between tibial bone lead concentration and scores for vocabulary, vibrotactile thresholds of the fingers, and vibrotactile thresholds of the toes approached significance. CONCLUSIONS: Significant adverse central and peripheral neurological effects were found in a group of young adults 20 years after childhood environmental exposure to lead when compared with non-exposed controls. The absence of a significant association between neurological outcomes and tibial bone lead concentration, and the presence of significant associations between neurological outcomes and exposure group may be due to either the magnitude of measurement uncertainty in K x ray films relative to the actual tibial bone lead concentration in these young non-occupationally exposed subjects, or uncontrolled confounding of the exposure group.     

Repair of O6-methylguanine in rat pancreatic beta-cells after exposure to N-methyl-N-nitrosourea

Because of the possible involvement of O6-methyldeoxyguanosine as a cytotoxic and carcinogenic lesion in pancreatic beta-cells, studies were undertaken to assess the ability of rat beta-cells to repair this DNA lesion. Primary cultures of neonatal rat beta-cells were shown to contain very low levels of O6-methylguanine-DNA-methyltransferase activity, the predominant mechanism for repairing O6-methyldeoxyguanosine in mammalian cells. However, using a 32P-endlabeling assay to measure O6-methyldeoxyguanosine in cells after exposure to N-methyl-N-nitrosourea, it was determined that rat beta-cells repaired O6-methyldeoxyguanosine to a substantial extent over a 24-h period. To elucidate the mechanism of O6-methyldeoxyguanosine repair in the virtual absence of constitutive O6-methylguanine-DNA-methyltransferase expression, studies were performed to determine if O6-methylguanine-DNA-methyltransferase expression was enhanced in N-methyl-N-nitrosourea-treated beta-cells. No increase in O6-methylguanine-DNA-methyltransferase activity was detected 24 or 48 h after exposure. However, Northern blot analysis showed a two- to threefold elevation in O6-methylguanine-DNA-methyltransferase messenger RNA levels in beta-cells 12 and 24 h after N-methyl-N-nitrosourea treatment. This finding is the first demonstration of a change in O6-methylguanine-DNA-methyltransferase messenger RNA levels in a cell type with low constitutive activity.     

Urinary excretion of phenols as an indicator of occupational exposure in the coke-plant industry

OBJECTIVE: In the present study the relationship between the level of exposure to o-cresol and of 2,4- +2,5-, 3,4-, and 3,5-xylenols and the urinary excretion of their metabolites was examined. The mixed exposure to phenolic derivatives of exposed workers during their work shift was monitored by personal air sampling of the breathing-zone air and by measurements of phenol, o-cresol, and xylenol isomer concentrations in shift-end urine. METHODS: The study subjects were 76 men working at a coke plant who were 22-58 years old and 34 nonexposed subjects. Concentrations of phenolic compounds were determined in the breathing-zone air during the work shift, whereas concentrations of phenol, cresol, and xylenol isomers were measured in urine collected after the work shift. Concentrations of phenols in air and urine were determined by gas chromatography with flame-ionization detection. Urine samples were extracted after acid hydrolysis of glucuronides and sulfates by solid-phase extraction. The gas chromatography-mass spectrometry method was applied to identify metabolites in urine samples. RESULTS: The time-weighted average concentrations of phenol, cresol, and xylenol isomers detected in breathing-zone air showed that the exposure level of the workers was relatively low. The geometric mean values were as follows: 0.26 mg/m3 for phenol, 0.09 mg/m3 for o-cresol, 0.13 mg/m3 for p- and m-cresol, and 0.02-0.04 mg/m3 for xylenols at the tar-distillation process. Corresponding urinary concentrations were 10.39, 0.53, and 0.25-0.88 mg/g creatinine for phenol, o-cresol, and xylenol isomers, respectively. The correlation coefficients between the o-cresol and 2,4-, 2,5-, 3,4-, and 3,5-xylenol concentrations measured in urine and in the breathing-zone air were statistically significant, varying in the range of 0.54-0.74 for xylenol isomers and being 0.69 for o-cresol. CONCLUSION: We have found that the presence of o-cresol and xylenol isomers in urine can be used as a biomarker for phenol exposure. Analysis performed on workers at the tar-distillation process showed that they were exposed to relatively low concentrations of phenolic compounds.     

A case cohort study of suicide in relation to exposure to electric and magnetic fields among electrical utility workers

BACKGROUND: All-trans retinoic acid is currently used in clinical trials in combination with tamoxifen to treat breast cancer, and 13-cis retinoic acid is used with a-interferon to treat metastatic endometrial cancer. We examined the effects of all-trans retinoic acid and 13-cis RA alone on endometrial adenocarcinoma (RL95-2) cells to investigate the cell biological mechanisms by which retinoic acid may reduce the metastatic phenotype and induce differentiation. METHODS: RL95-2 cells were seeded onto 4-chamber plastic slides and treated with 13-cis retinoic acid or all-trans retinoic at 0.5 microM, 1 microM and 5 microM doses for 90 minutes at 37 degrees C and stained for F-actin. RESULTS: Untreated RL95-2 cells exhibited staining of disrupted aggregates of F-actin only near the cell periphery. Cells treated with the three doses of 13-cis retinoic acid exhibited a dramatic reorganization of F-actin throughout the cells. When cells were treated with 0.5 microM all-trans retinoic acid, actin filaments reorganized. Cells treated with 1 microM all-trans retinoic acid and 5 microM all-trans retinoic acid displayed increased organization of F-actin and cell size increased. The percentage of S-phase cells increased at the high doses of retinoic acid treatment. This effect was apparently transient, since retinoic acid did not significantly affect cell growth. CONCLUSION: An organized cytoskeleton and an increase in cell size are associated with differentiation. We suggest that retinoic acid exerts its effects on these transformed cells by reorganizing actin filaments, and inducing differentiation, thus inducing a more stationary phenotype.     

Post-irradiation changes in blood 5'-nucleotidase activity of rats after chronic exposure to gamma irradiation

Kinetics of 5'-AMP hydrolysis by rat's blood serum was studied at 3, 10, 30, 90 and 180 days after prolonged gamma-irradiation at 0.1-1 Gy doses (60Co source, dose rate 4.4 x 10(-6) Gy/h). It was shown that more expressed kinetic anticooperativity of nucleotidase reaction in irradiated animals, as compare to control ones, was conditioned by composition predominance of low-affinity 5'-nucleotidases forms over their high-affinity patterns. The ratio of maximal velocities of high- to low-affinity 5'-nucleotidases was ranged from 2 in the control to 7 in irradiated rats at different postirradiation periods during the first 90 days of observation. It was suggested that appearance of new kinetic 5'-nucleotidases forms in blood stream of irradiated animals, predominantly with low-affinity, was attributed to impairment in the integrity of cellular membranes and may testify to postirradiation development of tissues injury.     

Retrospective estimation of exposure to benzene in a leukaemia case-control study of petroleum marketing and distribution workers in the United Kingdom

FK506 (tacrolimus), a potent immunosuppressant, is used for inhibiting allograft rejection in the organ transplantation field. In a preclinical toxicity study in rats, FK506 induced various toxicities, including renal and pancreatic injuries. One of these toxic findings was cataract, and we have found that cataract appeared in rats dosed orally with FK506 for 13 weeks and more. Therefore, to better elucidate the onset mechanism of FK506-induced cataract, we measured biochemical parameters, such as sorbitol, Na,K-ATPase and glutathione in the lens of rats. Rats were dosed with FK506 in oral daily doses of 0.2, 1 or 5 mg/kg for 13 weeks, the lowest dose of which approximated the expected clinical dosage. Cataract developed in the 5-mg/kg/day group, with an incidence of 25%, whereas no cataract formation was observed in the 0.2- or 1-mg/kg/day groups. Five mg/kg/day led an increase of sorbitol and a decrease of reduced type glutathione, but did not affect Na,K-ATPase activity of the lens. FK506 is known to have diabetogenicity mediated through pancreatic injury, which appears as vacuolation of islet cell in rats. Five mg/kg/day of FK506 induced an elevation of blood glucose associated with glucose intolerance, and decrease of both basal insulin level and insulin content in the pancreas, and the changes were in parallel with the cataract development in the present study. On the other hand, diabetic parameters did not change in the 0.2- or 1-mg/kg/day groups. These observation suggest that diabetes developed in the rats dosed with 5 mg/kg/day of FK506. Coadministration of a novel aldose reductase inhibitor, Zenarestat, at an oral dose of 50 mg/kg/day resulted in a reduction of incidence of the FK506-induced cataract and a decrease of sorbitol levels in the lens when compared to that in the lens of rats dosed with 5 mg/kg/day of FK506. These results suggest that FK506-induced cataract in rats is due to an accumulation of sorbitol in the lens, secondary to the diabetogenic effect of FK506. FK506 treatment at the doses of 0.2 and 1 mg/kg/day neither affected parameters indicative of diabetes nor induced cataract in rats, suggesting that the cataract would not develop with FK506 if diabetic parameters were kept under control.     

Evaluation of exposure to toxic factors occurring in the cellulose and paper industry

The study covered the work environment of a big plant producing sulfate cellulose, paper and paperboard. Measurements of chemical substance concentrations, performed by a local plant laboratory during the years 1976-1991, were analysed with reference to production departments and particular workplaces. Out of 37 substances under study, 16 were found in the air of workplaces. Their concentrations exceeded periodically hygienic standards. The most frequent excess of TLV applied to such compounds as wood dust (including hard beechwood), non-organic dusts containing 2-50% of crystalline silica and below 2% of silica, welding fumes, furfuryl aldehyde, sulfur dioxide, phenol and hydrogen sulfide. A computer-aided registrer of hygienic data facilitated the follow-up of dynamics of exposure to toxic compounds of workers employed at given workplaces.