Influence of Occupational and Environmental Exposure to Low Concentrations of Polychlorobiphenyls and a Smoking Habit on the Urinary Excretion of Corticosteroid Hormones.

The effects of occupational exposure to low concentrations of polychlorobiphenyls (PCBs) on the urinary excretion of corticosteroid hormones were evaluated, taking into account the influence of cigarette smoking. The study included 26 males working as electrical maintenance staff in a steel factory, previously exposed to a mixture of PCBs (exposed workers), and 30 male workers with no occupational exposure to PCBs (controls). Serum PCBs (33 congeners), urinary 17-hydroxycorticosteroids, 17-ketosteroids (KS) and pregnanes, and their respective glucuronidated and sulfonated compounds, were determined for each subject. PCBs were significantly higher in the exposed workers than controls, and were correlated with age. Both the urinary concentrations of the total 17-KS and pregnanes, and those of some single steroids and their glucuronidated compounds, were significantly lower in the exposed workers than controls, but higher in smokers than the non-smokers + ex-smokers. Two-way analysis of variance showed a negative association between serum PCBs and both total glucuronidated 17-KS and total and glucuronidated pregnanes, and a positive association between cigarette smoking and both total and glucuronidated 17-KS. PCBs seem to act as endocrine disruptors by reducing the urinary excretion of corticosteroid hormones, particularly of the glucuronidated fraction. Cigarette smoking could boost these effects of PCBs in smokers.

[Protocols for the health surveillance of fisherman]. / Protocolli per la sorveglianza sanitaria dei lavoratori della pesca.

AIM: To define protocols for health surveillance of workers in the marine fishing sector for specific occupational risk factors, considering the latest and most advanced scientific knowledge. MATERIALS AND METHODS: The specific literature was analyzed to identify the occupational risk factors to which fishermen are exposed. Then, for each risk factor a protocol for the relative health checkups and their time schedule was defined. RESULTS AND DISCUSSION: The risk factors to which fishermen are exposed are essentially noise, vibrations, solar and ultraviolet radiation, climatic agents (heat, cold, wind, rain, damp), chemical agents, shifts, work rate, night work, physical strain, stress, manual handling of loads, upper limb repetitive tasks, incongruous postures. The health protocols stipulate the health screening investigations to be carried out in all workers of a homogeneous group, and in-depth diagnostic investigations to be carried out in symptomatic workers. Complementary health investigations must be focused on a functional exploration of the organs specifically exposed to the risk factor. For hearing impairments due to noise exposure, the medico-legal measures with which the occupational health physician must comply, in cases of occupational disease, are indicated.

[Monitoring of the occupational and environmental exposure to low doses of benzene]. / Il monitoraggio dell'esposizione occupazionale ed ambientale a basse dosi di benzene.

AIM: To verify which of the various biomarkers of internal dose of benzene can be considered reliable for biological monitoring of exposure to the low concentrations present nowadays in working and living environments. MATERIALS AND METHODS: The specific literature was analyzed to assess the reliability of the different biomarkers of internal dose. RESULTS AND CONCLUSIONS: T,t-muconic acid is a non specific biomarker for benzene, valid for exposure to concentrations up to one order of magnitude less than the threshold limit of 3250 microg/m3. S-phenylmercapturic acid (SPMA) is a reliable marker even for exposure to concentrations up to two orders below the threshold value of 3250 microg/m3, and can be considered the biomarker of choice for biological monitoring of workers exposed to benzene. Urinary benzene does not seem to have any real advantages over SPMA for monitoring occupational exposure to benzene, but it does seem to be more reliable than SPMA to assess exposure to concentrations like those present in living environments. A smoking habit influences the urinary excretion of all the described biomarkers, and for the current low levels of occupational and environmental exposure to benzene, must be taken into account when interpreting the results of biological monitoring.

A pilot risk assessment study of strontium chromate among painters in the aeronautical industry.

OBJECTIVE: A method for risk assessment of occupational exposure to strontium chromate (SrCrO4) in painters employed in the aeronautical industry is described. METHODS: Assessment was made of 21 male workers of the painting division, potentially exposed to SrCrO4 (exposed), and 20 male workers of the tests and warehouse divisions (controls). All participants completed a questionnaire about work tasks, lifestyle habits, hobbies and diet. Personal active sampling for the determination of Cr and Sr was performed both during paint-spraying and during other operations in the painting division area. On the same day as environmental sampling, urine samples were collected at the beginning and end of the work shift in exposed workers to determine urinary chromium (CrU), and only at the end of the shift in controls. In the second half of the shift, a blood sample was taken in 10 exposed workers and 10 controls, to determine Cr in plasma (CrP) and in red blood cells (CrRBC). RESULTS: During paint-spraying, Cr concentrations ranged between 1.38 and 17.10 microg/m3, versus 0.02 to 0.07 microg/mi in the painting division area, while the Sr concentration was 22.90 microg/m3 in the paint-spray booth versus 0.07 microg/m3 in the painting division area. CrU at the end of the work shift, CrP and CrRBC, did not show significant differences between exposed workers and controls. Moreover, in exposed workers there were no differences between CrU measured at the beginning and at the end of the work shift. CONCLUSIONS: This approach, consisting of simultaneous environmental and biological monitoring, suggested no absorption of chromium in the painters thanks to the efficacy of the technical, organizational and personal protection measures adopted. However, the evident exposure to high levels of SrCrO4 during paint-spraying highlights how absolutely essential it is to ensure strict compliance with all the preventive measures foreseen by the EU and national regulations for occupational exposure to carcinogens.

Environmental factors affecting the urinary excretion of inorganic arsenic in the general population.

OBJECTIVE: To assess the critical issues concerning the use of urinary inorganic arsenic (iAs), including As3, As5, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), as biomarker of internal dose in order to monitor environmental and occupational exposure to inorganic As, considering the influence of diet and drinking water on excretion of iAs. METHODS: The design protocol stipulated collection of weekly urine samples from 6 male subjects for 5 consecutive months. In all the urine samples, iAs was determined by Hydride Generation-Atomic Absorption Spectrophotometry (HG-AAS). In the subjects with iAs higher than 35 microg/L, Biological Exposure Index (BEI) proposed by the American Conference of Governmental Industrial Hygienists (ACGIH), urinary arsenic speciation was performed by HPLC-ICP-MS. Exposure to airborne As was evaluated monthly using personal environmental samplers worn for 8 hours. Throughout the study, the participants filled out a daily food diary, also detailing types of water drunk. RESULT: Exposure to airborne As was invariably below the limit of detection, equal to 1 ng/m3. A total of 77 urine samples were collected. iAs was always detectable and was higher in 7 urine samples, obtained from 5 of the 6 subjects examined, than the BEI. Among foods with a high As content, the intake of seafood and fish within 72 hours before providing the sample seems to be the principal source of the iAs concentrations, while the intake of rice or drinking water showed no influence on this biological marker. Instead, drinking wine within 24 hours before urine sample collection can cause a significant increase in the excretion of iAs. CONCLUSIONS: In populations that eat large amounts of fish and seafood, the use of iAs to monitor occupational and environmental exposure to inorganic As seems to present some problems, and urinary As speciation may be essential at least in cases with As measurements above the biological limit values. In any case, a diet sheet reporting all foods eaten within 3 days of urine collection seems to be an indispensable tool to ensure a correct interpretation of the results.

[Health risk assessment of exposure to metals in the workers of the steel foundry and in the general population of Taranto (Italy)]. / Valutazione del rischio per la salute do esposizione a elementi metallici nei lavoratori del siderurgico e nella popolazione generale di Taranto (Italia).

OBJECTIVE: To study the urinary excretion of As, Cr, Mn, Co, Ni, Cu, Zn, Cd, Sn, Ba, Hg, Pb, Sb in workers at the Taranto integrated-cycle steel foundry and in subjects from the general population of Taranto, to assess the health risk posed by occupational exposure and environmental exposure, respectively, to these metals. MATERIALS AND METHODS: The study included 49 steel foundry workers (exposed), working in the minerals and agglomerates pools, steel processing plants 1 and 2 and maritime plants, and 50 subjects belonging to the general population of Taranto resident at various distances from the factory (controls), randomly selected from the exposed subjects and controls enrolled in previous research conducted in 2005. A questionnaire was administered to all participants, enquiring into general characteristics, lifestyle, diet, and any medical conditions. Informed written consent to take part in the study was obtained from all subjects before enrolment. The results of environmental monitoring performed in 2005 in the workers' sectors, consisting of determining As, Cr, Mn, Ni, Cu, Zn, Cd and Pb in the respirable dust, revealed by both samplers applied in fixed positions and personal samplers, were considered. Urine samples were obtained from all participants on a Friday, to determine As and Cr by AAS and all the other metal elements by a multielement technique with ICP-MS. Urinary creatinine was also determined to make any necessary adjustments. All urine analyses were performed in 2005 within one month of urine collection. RESULTS: In the respirable dust, As and Cd were always within the LOD, whereas Cr, Mn, Ni, Cu and Pb were 1-2 orders of magnitude below the respective TLV-TWA of the ACGIH. Mn was the only metal element that presented significantly higher urinary concentrations in exposed subjects as compared to controls, although the values in both groups were in any case within the Italian reference range. Co, Cu, Zn, Sn and Sb showed significantly higher urinary concentrations in controls than in the exposed subjects, while there were no differences in As, Cr, Cd, Ba, Hg and Pb between the two groups. Ni was within the LOD in the 60% of the subjects in the two groups. Multiple stepwise regression showed a dependence of Cr on age, of As on the number of days since the last meal of mollusks and crustaceans, of Zn on the consumption of mollusks, and of Cd and Pb on smoking expressed as the number of pack/year. DISCUSSION: The research did not reveal higher urinary excretion of the metal elements in the steelworkers than in the subjects from the general population of Taranto resident at different distances from the factory, except for Mn, that was anyway within the reference range. This allows us to consider that there is no relevant health risk posed by occupational exposure to metal elements in the steelworkers, nor by environmental exposure to the same elements in the residents of the city of Taranto. In particular, no pollution of the living environment by metal elements of industrial origin was demonstrated, whereas other non occupational factors seem to condition the intake of these metal elements.

The influence of diet on intra and inter-individual variability of urinary excretion of arsenic species in Italian healthy individuals.

To study the effect of eating foods with a high arsenic (As) content on the intra and inter-individual variability of urinary concentrations of the As species, daily urine samples were collected for 10 consecutive days from 12 healthy male subjects. A daily food diary was kept throughout the study period. Personal exposure to airborne As was measured once during the study. As(3), As(5), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and arsenobetaine were determined in all urine samples by inductive coupled plasma mass spectrometry, and the sum of As(3)+As(5)+MMA+DMA (iAs) by hydride generation-atomic absorption spectrophotometry. Exposure to airborne As was below the limit of detection in all samplings. As(3) was found in only 19.2% and As(5) in only 3.3% of the urine samples, whereas high urinary concentrations of arsenobetaine were observed. With the exception of arsenobetaine, expressed as a percentage, a significant inter-individual variability was observed for all species of As, for iAs and for the MMA/DMA ratio (p<0.001). Instead, the intra-individual variability was significant only for the MMA/DMA ratio (p<0.001). Among foods with a high As content, only a heavy consumption of seafood was shown to influence inter-individual variability of DMA%, arsenobetaine expressed as µg g(-1) creatinine and iAs. In conclusion, even in populations with a high intake of organic As through foods, the finding of a significant inter-individual but no significant intra-individual variability of urinary species confirms the usefulness of urinary As speciation for biological monitoring of exposure to As.

Biomarkers of internal dose for the assessment of environmental exposure to benzene.

The urinary excretion of t,t-muconic acid (t,t-MA), S-phenylmercapturic acid (SPMA) and urinary benzene and the influence of a smoking habit and of exposure to urban traffic on the urinary excretion of these biomarkers were investigated in 137 male adults from the general population. All subjects were not occupationally exposed to benzene and resident in two cities in Puglia (Southern-Italy). Environmental exposure to benzene was measured using passive personal samplers. The biomarkers t,t-MA, SPMA and urinary benzene were determined in urine samples collected from each subject at the end of the environmental sampling. The percentage of cases above the limit of detection was higher for SPMA and urinary benzene in smokers than in non-smokers, and for airborne benzene and urinary benzene in subjects exposed to urban traffic. Airborne benzene was correlated with the time spent in urban traffic during the environmental sampling. Among the biomarkers, urinary benzene was found to be correlated with airborne benzene only in non-smokers, and with the time spent in urban traffic, both in smokers and non-smokers considered together, and in non-smokers only. Finally, multiple regression analysis showed that the urinary excretion of all the biomarkers was dependent on the number of cigarettes smoked per day and, for urinary benzene, also on the time spent in urban traffic. In conclusion, urinary benzene seems to be a more valid biomarker than t,t-MA and SPMA to assess environmental exposure to extremely low concentrations of benzene. Cigarette smoking prevailed over traffic exhaust fumes in determining the internal dose of benzene.

Validity of new biomarkers of internal dose for use in the biological monitoring of occupational and environmental exposure to low concentrations of benzene and toluene.

OBJECTIVES: This study analyzes the validity of new, more sensitive and specific urinary biomarkers of internal dose, namely, urinary benzene for benzene and urinary toluene and S-benzylmercapturic acid (SBMA) for toluene, to assess their efficacy when compared to traditional biomarkers for biological monitoring of occupational exposure to low concentrations of these two toxic substances. METHODS: Assessment was made of 41 workers occupationally exposed to benzene and toluene, 18 fuel tanker drivers and 23 filling-station attendants, as well as 31 subjects with no occupational exposure to these toxic substances (controls). Exposure to airborne benzene and toluene was measured using passive Radiello personal samplers worn throughout the work shift. In urine samples collected from all subjects at the end of the workday, both the traditional and the new internal dose biomarkers of benzene and toluene were assessed, as well as creatinine so as to apply suitable adjustments. RESULTS: Occupational exposure to benzene and toluene resulted significantly higher in the fuel tanker drivers than the filling-station attendants, and higher in the latter than in controls. Significantly higher concentrations of t,t-muconic acid (t,t-MA), S-phenylmercapturic acid (SPMA), urinary benzene, SBMA and urinary toluene were found in the drivers than the filling-station attendants or the controls. Instead, urinary phenol and hippuric acid were not different in the three groups. In the entire sample, airborne benzene and toluene values were significantly correlated, as were the respective urinary biomarkers, showing coefficients ranging from 0.36 to 0.98. Subdividing the subjects by smoking habit, higher coefficients were evident in non-smokers than in smokers; at multiple regression analysis t,t-MA, SPMA and urinary benzene and toluene were dependent on the number of cigarettes smoked daily and on airborne benzene and toluene, respectively. Instead, SBMA was dependent only on airborne toluene. CONCLUSIONS: Our research confirmed the validity of t,t-MA and SPMA for use in the biological monitoring of exposure to low concentrations of benzene. Urinary benzene showed comparable validity to SPMA; both parameters are affected by smoking cigarettes in the hours before urine collection, so it is best to ask subjects to refrain from smoking for 2 h before urine collection. Urinary toluene was found to be a more specific biomarker than SBMA.