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ObjectivesThe increase in production of multiwalled carbon nanotubes (MWCNTs) has led to growing concerns about health risks. In this study, we assessed the association between occupational exposure to MWCNTs and cardiovascular biomarkers.MethodsA cross-sectional study was performed among 22 workers of a company commercially producing MWCNTs (subdivided into lab personnel with low or high exposure and operators), and a gender and age-matched unexposed population (n=42). Exposure to MWCNTs and 12 cardiovascular markers were measured in participants’ blood (phase I). In a subpopulation of 13 exposed workers and six unexposed workers, these measures were repeated after 5 months (phase II). We analysed associations between MWCNT exposure and biomarkers of cardiovascular risk, adjusted for age, body mass index, sex and smoking.ResultsWe observed an upward trend in the concentration of endothelial damage marker intercellular adhesion molecule-1 (ICAM-1), with increasing exposure to MWCNTs in both phases. The operator category showed significantly elevated ICAM-1 geometric mean ratios (GMRs) compared with the controls (phase I: GMR=1.40, P=1.30E-3; phase II: GMR=1.37, P=0.03). The trends were significant both across worker categories (phase I: P=1.50E-3; phase II: P=0.01) and across measured GM MWCNT concentrations (phase I: P=3.00E-3; phase II: P=0.01). No consistent significant associations were found for the other cardiovascular markers.ConclusionThe associations between MWCNT exposure and ICAM-1 indicate endothelial activation and an increased inflammatory state in workers with MWCNT exposure.

Following the 1984 Bhopal methyl isocyanate (MIC) gas disaster, genetic alterations were sporadically reported on small cohorts. However, the outcome of the multi-center cytogenetic screening conducted at that time remains unknown and no follow-up studies on the long-term effects of MIC exposure have been published. The present work examines genetic changes in the exposed population,with the aim of identifying any long-term effects of MIC. G-Banded metaphases were studied in lymphocytes of 130 individuals. Chromosomal aberrations (CA) were broadly grouped as abnormal cells (Abc), aberrations (Abn), and aberration/abnormal cell (Abn/Abc). From the previous multi-center screening, 946 records were retrieved, from which CA, sister chromatid exchanges (SCE), and cell-cycle kinetics (RI) were computed. In our analysis of the previous study, Abc and Abn were higher in the moderately and severely exposed groups than in the unexposed population. Abc appeared uniform in all groups of the present study, although Abn and Abn/Abc were higher in the exposed groups. Aberrations were now significantly higher in the unexposed and moderately exposed groups than in the previous screening. Although Abn and Abc now appeared lower in severely exposed subjects, the Abn/Abc ratio was higher, perhaps due to more rearrangements and damage in a smaller number of Abc. This result may be attributed to differences between the methods used in the studies, then and now. Elevated SCEs and reduced RI were seen in the severely exposed population shortly after exposure, and stable/clonal rearrangements were seen 30 y later. Follow-up of index cases and their progenies is needed.

In the 1980s, villages in the Kurdistan region of Iraq were exposed to chemical weapons (CWs), which killed and injured thousands of civilians. There has been no clinical assessment of the long-term effects of CWs exposure on those injured. We report the first such evaluation of CW effects on long-term health of children. Patients from the CW-exposed areas were interviewed to assess previous and current clinical history and underwent clinical examination. The status of organs known to be targets of CWs, including skin, eyes, respiratory and neuromuscular systems, was assessed. Children of similar age and social background, but with no history of CW exposure, were selected as a control population. Results showed that 70% of children in the CWs group had chronic health problems in contrast to 3.3% in the unexposed group ( p < 0.0001). Fifty-five per cent of the CW-exposed group had long-term visual impairment but none in the unexposed population. Thirty-six per cent of the CW-exposed group had chronic dermatological conditions compared with 0.8% of the unexposed group ( p < 0.0001), 31% of the CWs group had neurological sequelae compared with 0.4% of the unexposed group ( p < 0.0001) and 51% of the CWs group had long-term respiratory problems compared with 1.5% of the unexposed group ( p < 0.0001). Respiratory complaints including asthma, chronic bronchitis and bronchiectasis were particularly common. Our study suggests that CWs used were probably a combination of sulphur mustard and organophosphate nerve agents. Results also indicate that the prevalence of acute and chronic health problems following exposure to CW agents appear to be higher in children compared with reported data in adults.

Introduction Eastern and North-Eastern regions of Kazakhstan are considered to be environmentally disadvantaged due to industrial pollution and activity of the former Semipalatinsk Nuclear Test Site. Ferrous metallurgy is represented by the world’s largest ferroalloy plant located in Aksu. In addition to a ferroalloy plant, Aksu is the home for the largest thermal power plant in Kazakhstan. Objective Biomonitoring of 31 hair and blood trace elements (Ag, Ba, Be, Bi, Cs, Co, Ce, Cr, Cu, Eu, Gd, Hf, In, La, Li, Mn, Mo, Nb, Nd, Pb, Sc, Sn, Tl, Th, U, V, W, Y, Yb, Zn, and Zr) in non-occupationally exposed population residing in polluted areas of East Kazakhstan and Pavlodar regions. Methods Five case groups, residing in the vicinity to the former Semipalatinsk Nuclear Test Site (Akzhar, Borodulikha, and Karaul) or in proximity to industrial plants (Aksu and Ust-Kamenogorsk) have been assessed vs. controls from a rural settlement in Kurchum. In total, 204 hair and blood samples were analyzed by inductively coupled plasma mass spectrometry. Results The observed blood concentrations of trace elements were in agreement with earlier studies on residents of industrially polluted areas. Elevated levels of blood Ba, Mn, Pb, V, and Zn were detected in residents of Aksu and Ust-Kamenogorsk. The elemental composition of head hair was characterized by greater stability between the study sites. Conclusion Residency near the former Semipalatinsk Test Site could be considered as safe, while the environmental status of industrial settlements appears to be rather adverse.

Background: Occupational crystalline silica dust exposure is associated with an elevated risk of pulmonary tuberculosis (PTB). However, there is less evidence for an association with environmental silica dust exposure. Methods: A cross-sectional study of 310 participants was conducted in an exposed community living within 2 km of gold mine tailings and an unexposed population residing more than 10 km from the nearest gold mine tailing. Chest radiographs (n = 178) were read for PTB, past or current, by three readers. Results: Past or current PTB was radiologically identified in 14.4% (95%CI 9.2&ndash, 21.8) in the exposed and 7.5% (95%CI 2.8&ndash, 18.7) in the unexposed groups. Multivariate logistic regression models suggested that PTB prevalence was independently associated with exposure to second-hand smoke (OR = 8.13, 95%CI 1.16&ndash, 57.22), a lower body mass index (OR = 0.88, 95%CI 0.80&ndash, 0.98), previous diagnosis and treatment of PTB (OR = 8.98, 95%CI 1.98&ndash, 40.34), and exposure to dust in the workplace from sand, construction, and/or mining industries (OR = 10.2, 95%CI 2.10&ndash, 50.11). Conclusion: We found no association between PTB and environmental exposure to gold mine tailing dust. However, workplace silica dust exposure is a significant risk factor for PTB in South Africa, and PTB patients of working age should be screened for silica exposure.

Introduction Few studies on cancer incidence have been conducted since the adoption of the EU 2000/76/EC waste incineration directive which aimed to limit dioxin emission levels to less than 0.1 ng TEQ/m3 before December 31, 2005. Objective To measure cancer incidence among the population exposed to atmospheric emissions from the waste incineration plant near the town of Nice (South-Eastern France), compared to the unexposed population of the Alpes-Maritimes department (A-M). Methods All primary invasive cancers and haematological malignancies diagnosed among AM residents between 2005 and 2014 were recorded. The exposed surface was modeled on an average dioxin deposition model ≥4.25 ng/m2/year. Each case was geolocated and assigned to one of 36 predefined geographic units of exposed area, or one of 462 units in the unexposed area. The adjusted incidence rate, the standardized incidence ratio and the Comparative Morbidity Figure were calculated for two periods: 2005-2009/2010-2014. Results We recorded 80,865 new cancers in the A-M population. Between 2005 and 2009, we observed a higher incidence among exposed women of acute myeloid leukaemia, myelodysplastic syndromes and myeloma and, among exposed men, of soft tissue sarcomas, myeloma and lung cancer. Between 2010 and 2014, there was no excess incidence among women, while among men incidence of myeloma and lung cancer remained higher. Conclusion Only among men, the incidence of myeloma and lung cancer remained higher in the exposed area during the second period. The EU directive resulting in the limitation of atmospheric emissions from incinerators could explain the decrease in incidence of cancers with protracted latency. Consideration of other risk factors and further data collection will be necessary to validate this hypothesis.

The present study investigates the rates of depression, anxiety, somatic distress, and fatigue in a rural population of Abayskiy, Borodulikha and Mayskiy districts exposed to radiation from Semipalatinsk Nuclear Test Site in comparison with the unexposed population of Kurchum district. The sample size included 901 people, of whom 656 were residents of radioecological contaminated areas, while 245 resided at ecologically safe territories and had no radiation exposure in the past. Both study groups had no significant differences concerning age, sex, level of education, smoking habit, and alcohol consumption. The prevalence of depression, anxiety, somatic distress and fatigue in the exposed group was found to be considerably higher than that in the unexposed. Results of logistic regression analysis showed considerable differences in associations between depression and anxiety, as wells as between depression and somatic distress in the exposed group. Besides, depression was significantly associated with general fatigue, reduced activity, physical fatigue, reduced motivation and mental fatigue in the unexposed group. There is a need to tailor public health interventions focused on the identification and management of individuals exhibiting mental distress, including the provision of adequate information about radiation-induced health effects, quality routine check-ups and psychological counseling.

BACKGROUND Studies comparing different forms of asbestos are rare, and limited by the failure to compare results with unexposed populations. We compare autoimmune responses among former workers and residents of the crocidolite mining and milling town of Wittenoom, Western Australia, with an unexposed population. METHODS ANA testing using indirect immunofluorescence was performed on randomly selected serum samples from Wittenoom workers or residents and compared with those from participants of another unexposed cohort study. RESULTS ANA scores were higher in the Wittenoom participants compared with Busselton and the odds of being ANA positive was fivefold greater among Wittenoom participants than Busselton (OR 5.5, 95%CI 2.3-13.0). CONCLUSIONS This study is the first to report increased ANA positivity among persons exposed exclusively to crocidolite. This finding of a high frequency of positive ANA tests among crocidolite-exposed subjects may be an indicator for an increased risk of systemic autoimmune diseases and needs further scrutiny.

The objective of present study was to assess relationship between biomarkers of Manganese (Mn) and neuropsychological effects. The study was carried out on 27 welders and 31 ferroalloy smelters as Mn-exposed groups and 30 office workers as unexposed controls. Air Mn concentrations were determined according to NIOSH method 7300. The biological samples were prepared using microwave assisted acid digestion and all samples were analyzed by graphite furnace- atomic absorption spectroscopy (GF-AAS) in order to determine manganese. Questionnaire 16 (Q16) and Cambridge Neuropsychological Test Automated Battery (CANTAB) were used to evaluate the neuropsychological effects. The mean concentrations of air Mn for the welder and ferroalloy smelter groups were 0.023 ± 0.012 mg/m(3) and 0.008 ± 0.005 mg/m(3), respectively. Manganese concentrations in blood, urine, and toenail samples of exposed workers ranged between 1.80-32.60 (µg/l), 1.00-42.50 (µg/l), and 0.10-6.08 (µg/g), respectively. Mean Mn concentrations in all biological samples of cases were significantly higher than unexposed controls (p

The National Center for Education Statistics reported that between 1990–2005 the number of children receiving special education services (SES) rose significantly, and then, from 2004–2012, the number declined significantly. This coincided with the introduction of Thimerosal-containing hepatitis B vaccine in 1991, and the subsequent introduction of Thimerosal-reduced hepatitis B vaccine in the early 2000s. This study examined the potential relationship between infant exposure to mercury from three doses of Thimerosal-containing hepatitis B vaccine and the risk of boys being adversely affected (as measured by receipt of SES). This cross-sectional study examined 1192 boys (weighted n = 24,537,123) 7–8 years of age (born: 1994–2007) from the combined 2001–2014 National Health and Nutritional Examination Survey (NHANES). Survey logistic regression modeling revealed that an exposed population receiving three doses of infant Thimerosal-containing hepatitis B vaccine (weighted n = 11,186,579), in comparison to an unexposed population (weighted n = 704,254), were at an increased risk of receipt of SES. This association was robust (crude odds ratio = 10.143, p = 0.0232), even when considering covariates, such as race and socioeconomic status (adjusted odds ratio = 9.234, p = 0.0259). Survey frequency modeling revealed that receipt of SES for the population that was exposed to three doses of Thimerosal-containing hepatitis B vaccine in infancy (12.91%) was significantly higher than the unexposed population (1.44%) (prevalence ratio = 8.96, p = 0.006, prevalence attributable rate = 0.1147). Despite the limitation of this cross-sectional study not being able to ascribe a direct cause-and-effect relationship between exposure and outcome, it is estimated that an additional 1.2 million boys received SES with excess education costs of about United States (US) $180 billion associated with exposure to Thimerosal-containing hepatitis B vaccine. By contrast, exposure to Thimerosal-reduced hepatitis B vaccine was not associated with an increased risk of receiving SES. Therefore, routine childhood vaccination is important to reduce the morbidity and mortality of infectious diseases, but every effort should be made to eliminate Thimerosal from all vaccines.

The aim of this study was to assess eight firefighters' exposure to Sthamex 3% AFFF (aqueous film forming foam) in the simulation of aircraft accidents at Oulu airport in Finland. Study was conducted in 2010 before limitation for the use of PFOA and PFOS in AFFFs. Due to prospective limitation also eight commercially available AFFFs were evaluated from occupational and environmental point of view to find substitutive AFFFs for future. The firefighters' exposure to twelve perfluoroalkyl acids (PFAS) was analyzed in order to observe the signs of accumulation during three consecutive training sessions. The firefighters' short-term exposure to 2-butoxyethanol (EGBE) was analyzed by urinalysis of 2-butoxyacetic acid (2-BAA). For the background information also the concentration of PFAS in used AFFF-liquid was analyzed. Fire fighters' serum PFHxS and PFNA concentrations seemed to increase during the three training sessions although they were not the main PFAS in used AFFF. The statistical significance for the elevations was not able to test due to limited size of test group. In two training sessions, the average urinary excretions of 2-BAA exceeded the reference limit of the occupationally unexposed population. In the evaluations of the firefighting foams, non-fluorine based products were favored and the alcohol resistance properties of foams were recommended for consideration due to the increasing use of biofuels.

Arsenic in drinking water presents a serious public health problem in Serbia, but its relationship with diabetes has not been studied previously. The aim of this study was to explore the association between exposure to arsenic in drinking water and the occurrence of type 2 diabetes in Middle Banat region, Serbia. This cross-sectional study comprised two populations. Exposed population in Middle Banat region consumes drinking water with arsenic (mean = 56 μg/L); unexposed population from six regions in Central Serbia consumes arsenic below detection limit (2 μg/L). Newly diagnosed cases of type 2 diabetes were obtained from the National Registry of Diabetes in 2008. The Registry included age, gender, family history of diabetes, presence of overweight, central obesity, cholesterol and triglyceride levels. In addition, the number of cases of diabetes reported in years 2006, 2007 and 2009 was used to calculate standardized incidence rates for both populations. Two populations were comparable by age, family history of diabetes and prevalence of overweight persons. Unexposed population was more likely to have central obesity, and high total cholesterol and triglycerides. Standardized incidence rates of type 2 diabetes were higher in exposed population. Odds ratios for type 2 diabetes were significantly higher for the exposed population, both men and women, in the period from 2006 to 2009, when compared with the unexposed population. The population from Middle Banat region, consuming drinking water with low levels of arsenic, was at higher risk for the occurrence of type 2 diabetes in comparison to the unexposed population in Central Serbia.

To evaluate measures of health-related quality of life in a cohort study in Taiwan to assess late health effects of protracted low-dose-rate γ-radiation exposure during 1982 to the mid-1990s.In 2004, 1,407 cohort subjects were evaluated by a self-measured World Health Organisation-Brief quality of life Questionnaires (WHOQOL-BREF Taiwan version) during an annual medical check-up in a hospital. Results of their health-related quality of life (HRQoL) in physical, psychological, social relationship and environmental domains were compared with an unexposed reference population in the same city.The exposed population was shown to have significantly lower quality of life (QOL) scores in physical, psychological and social relationship domains, but not in the environmental domain compared to the unexposed population. These findings were observed in all age groups with the greatest decrease found among those younger than 25 years old. Female subjects were shown to have larger decrease than male subjects.More than 10 years after being informed of radiation exposure, the exposed populations were observed to have significantly lower perception of HRQoL even though no biomedical effects were apparent. It is recommended that appropriate intervention be carried out in the follow-up of post-event rehabilitation for the radiation exposed.

Purpose There are a limited number of case reports confirming the radioiodine (I-131) presence in tears and only a few case reports of lacrimal gland dysfunction after I-131 therapy. This study was designed to clarify whether lacrimal gland function can be affected by I-131 therapy. Materials and methods We studied 100 eyes of 50 patients who had received high doses of I-131 for treatment of differentiated thyroid carcinoma and 100 eyes of 50 age- and sex-matched control individuals without a history of interfering conditions. The exposed group was studied at least 3 months after their last I-131 therapy. Dry eye symptoms and Schirmer test values (wetting level in millimeters per 5 minutes) of an exposed group were compared with those of an unexposed group. Results Fifty-one percent of the exposed eyes and 50% of the unexposed ones revealed at least 1 of the dry eye symptoms. There was no significant difference in symptoms between 2 groups, except for burning sensation and eye redness, which were significantly higher in the exposed eyes. A lower Schirmer test value was noted in the exposed group, 14.5 +/- 10.8 mm, when compared with that in controls, 18.2 +/- 11.0 mm (P = 0.016), and the relative risk of an abnormal Schirmer test in exposed cases to control group was 1.78 +/- 0.62. Correlation coefficient analysis showed no significant relationship between Schirmer test values and cumulative doses of administered I-131. Conclusions Reduction in the tear secretion from lacrimal glands is seen after high-dose I-131 therapy; however, their symptoms are no greater than an unexposed population.

The paper discusses the content of elements in hair of subjects studied over several years. The study was performed on 5 subjects (N=28) that lived together or were family related. The elemental composition of hair of the studied subjects was compared with the average content of the population living in the same urban area (Wroclaw city, south-west Poland), with the population of a non-industrialized area in Poland (Silesian Beskid), as well as with the population of north-east Sweden and Rio de Janeiro. When comparing the composition of hair from the studied subjects with the people living in the same city, it was found that the differences resulted mainly from different living habits (Na, Si, Co, Fe, Mn, Zn) and local exposure (Pb, Cd, Al). When comparing with the reference material for unexposed population, it was found that the studied subjects were exposed to Al. Time profile of element contents in hair of a given person showed that the level changed significantly (even several fold) with changes of living habits or environmental exposure. Also, it was found that there were similar tendencies in the accumulation of the majority of elements by people that lived together. The effect of living habits on the level of a given element was found to be stronger than the influence of either sex or family relationship. The paper also discusses inter-element interactions within the studied group. Statistically significant (p

The role of nutritional factors in arsenic metabolism and toxicity is not clear. Provision of certain low protein diets resulted in decreased excretion of DMA and increased tissue retention of arsenic in experimental studies. This paper reports a prevalence comparison study conducted in Bangladesh to assess the nutritional status among the chronic arsenic exposed and unexposed population. 138 exposed individuals diagnosed as arsenicosis patients were selected from three known arsenic endemic villages of Bangladesh and age, sex matched 144 unexposed subjects were randomly selected from three arsenic free villages. The mean arsenic concentration in drinking water for the exposed and unexposed population was 641.15 and 13.5 microg L(-1) respectively. Body Mass Index was found to be lower than 18.5, the cut off point for malnutrition, in 57 (41.31%) out of 138 exposed arsenicosis cases and 31 (21.53%) out of 144 unexposed individuals. The crude prevalence ratio (or risk) was 1.92 (95% CI = 1.33-2.78) for poor nutritional status among the arsenicosis cases compared to the unexposed population. The findings of this study add to the evidence that poor nutritional status may increase an individual's susceptibility to chronic arsenic toxicity, or alternatively that arsenicosis may contribute to poor nutritional status.

This study was conducted to investigate the possible long-term health effects, in particular carcinogenic effects, of occupational exposure to the organochlorine insecticides dieldrin and aldrin. We updated an earlier cohort mortality study of 570 employees involved in the production of these insecticides. All of the employees had worked in the production plants between 1 January 1954 and 1 January 1970 and were followed for cause-specific mortality until 1 January 2001. Based on dieldrin levels in blood samples taken during the exposure period, available for 343 workers, individual estimates of the total intake of dieldrin were estimated for all individual subjects in the cohort. The estimated total intake ranged from 11 to 7755 mg of dieldrin, with an average of 737 mg. One hundred and seventy-one workers had died before 1 January 2001, compared with an expected number of 226.6, giving a standardized mortality ratio (SM R) of 75.6 [95% confidence interval (CI): 64.6-87.7]. This deficit in total mortality was mainly attributable to a deficit in cardiovascular disease mortality, but cancer mortality was also lower than expected. The observed number of deaths from rectal cancer was significantly higher than expected (SM R 3/4-300.0; 95% CI: 109.5-649.3), but was most pronounced in the low-intake subgroup and appears to be unrelated to exposure to dieldrin and aldrin. This study reinforces the earlier findings that occupational exposure of workers to significant amounts of dieldrin and aldrin has not led to a higher cancer mortality than would be found in an unexposed population.

While blood lead levels (BLLs) in many western countries have progressively declined since 1976, in Nigeria high BLL continue to be documented not only in exposed workers but also in "unexposed" control subjects. The problem of environmental lead exposure has hitherto gone unaddressed by both researchers and health policy makers in Nigeria despite the immense public health importance. Continued high BLLs in Nigeria cast doubt on researchers' ability to find real "unexposed control subjects" in future studies, and point to the importance of controlling environmental lead exposures.

The recent article, “Analyses of Radiation and Mesothelioma in the US Transuranium and Uranium Registries,” by Gibb et al.1 examines seven mesothelioma deaths among a small population of 329 deceased registrants in the US Transuranium and Uranium Registries (USTUR). Using the National Institute for Occupational Safety and Health’s Life Table Analysis System with the referent group being all deaths in the United States,2,3 the study finds a proportionate mortality ratio (PMR) of 62.40 (P

The element lead (Pb) has been very widely studied in man due to its widespread occurrence and toxic effects. There is no known nutritional value of Pb and it is stored in the bone by replacing calcium. In the cellular level, Pb alters cell membrane structure and membrane on function. It is a potent inhibitor of the Na{sup +} K{sup +} ATPase. Pb also interferes with the activity of the enzymes delta-aminoevulinic acid synthetase, delta-aminolevulinic dehydrase and intra-mitochondrial ferrochelatase. In the pre-natal level, Pb-exposure may lead to an increased risk of prematurity and reduction of gestational age in humans. Pb-exposure causes adverse neuro-psychological effects among young children and numerous endrocrinal disturbances among adults. It has shown that Human Scalp Hair (HSH) Pb concentration can be used very successfully to document population exposure to this toxic element. Copper is known to be biologically essential, but Cu poisoning is rare in humans. This study attempts to document exposure and to determine `base-line` values for HSH Pb and CU among three occupationally unexposed population groups in Calcutta. 15 refs., 1 tab.

The aim of the study was to investigate hematopoietic injury and recovery in residents of the Techa riverside villages who had been chronically exposed to radiation as a result of the activities of the Mayak Nuclear Facility, and evaluate late effects from chronic, low-dose radiation exposures. Whole blood samples were drawn from 338 unexposed individuals resident in noncontaminated villages, and 692 individuals chronically exposed externally (to primarily gamma radiation) and internally from 90 Sr since 1949 at decreasing dose-rates which have currently reached the background levels. The mean cumulative dose in the exposed cohort was 0.62 Gy over the years 1949 to 2008 using the Techa River Dosimetry System (TRDS) 2000. The frequency of chromosome aberrations and mutations in peripheral lymphocytes, and other aspects indicative of cellular and molecular repair of radiation damage, were measured. The subjects were divided into two study groups: (a) 171 individuals who during the early exposure period (where the highest dose-rates were prevalent) were noted to manifest leucopenia and/or were diagnosed with chronic radiation syndrome (CRS), and (b) 521 exposed individuals without cytopenia and CRS. The first group demonstrated an increased frequency of micronuclei, dicentric chromosomes, somatic mutations (CD3-CD4+cells) in lymphocytes, and mutations in the TP53 gene. In addition, they demonstrated a lower Cu/Zn-SOD concentration, a significantly increased concentration of nitric oxide, and a greater apoptotic frequency in peripheral blood lymphocytes compared to exposed individuals without leucopenia. Similar to the unexposed individuals, the second group demonstrated "background levels" of mutational frequencies several years after their exposures, but they did show an increased number of cells with delayed cell cycles based on Chk-2 concentrations compared to the unexposed population. The data are consistent with the idea that a chronic radiation exposure within a dose range from 0.01 Gy to 1.96 Gy results in more severe late hematopoietic effects in a select cohort of highly radiosensitive individuals, rather than an overall increase in late effects in cells of each exposed individual. The authors state that radiation-exposed subjects demonstrating CRS showed an activation of barrier anti-oxidative stress mechanisms at late periods after radiation exposure, apparently in response to a more severe radiation damage than subjects exposed to similar radiation doses but not demonstrating CRS. Finally, the persistence of chromosome aberrations and somatic mutations in the CRS cohort is indicative of an exhaustion of the anti-oxidative stress mechanisms responding for so many years after the exposure, leading to genomic instability.

The effect of exposure to cadmium, lead, or manganese on male reproductive function was examined in 1988-1989 in Belgian blue-collar workers. The workers were exposed to cadmium in two smelters (n = 83; geometric mean urinary cadmium level = 6.94 micrograms/g of creatinine; mean duration of exposure = 24 years), to lead in a battery factory (n = 74; mean blood lead level = 46.3 micrograms/dl; mean duration of exposure = 10.7 years), or to manganese (manganese dioxide) in a dry alkaline battery plant (n = 70; median atmospheric concentration of total manganese dust = 0.71 mg/m3; mean duration of exposure = 6.2 years). Fertility in these workers and in an unexposed population (n = 138) was assessed by examining the birth experiences of their wives through a logistic regression model. The probability of a live birth was not different between the unexposed workers and the cadmium- or manganese-exposed workers before or after the onset of exposure. While the fertility of the lead-exposed workers was somewhat greater than that of the unexposed before the onset of exposure, a significant decrease in fertility was observed during the period of exposure to the metal (odds ratio = 0.65, 95% confidence interval 0.43-0.98).

International audience; BACKGROUND: Persistent symptoms, mainly joint and muscular pain and depression, have been reported several months after Chikungunya virus (CHIKV) infection. Their frequency and their impact on quality of life have not been compared with those of an unexposed population. In the present study, we aimed to describe the frequency of prolonged clinical manifestations of CHIKV infection and to measure the impact on quality of life and health care consumption in comparison with that of an unexposed population, more than one year after infection. METHODOLOGY/PRINCIPAL FINDINGS: In a retrospective cohort study, 199 subjects who had serologically confirmed CHIKV infection (CHIK+) were compared with 199 sero-negative subjects (CHIK-) matched for age, gender and area of residence in La Réunion Island. Following an average time of 17 months from the acute phase of infection, participants were interviewed by telephone about current symptoms, medical consumption during the last 12 months and quality of life assessed by the 12-items Short-Form Health Survey (SF-12) scale. At the time of study, 112 (56%) CHIK+ persons reported they were fully recovered. CHIK+ complained more frequently than CHIK- of arthralgia (relative risk = 1.9; 95% confidence interval: 1.6-2.2), myalgia (1.9; 1.5-2.3), fatigue (2.3; 1.8-3), depression (2.5; 1.5-4.1) and hair loss (3.8; 1.9-7.6). There was no significant difference between CHIK+ and CHIK- subjects regarding medical consumption in the past year. The mean (SD) score of the SF-12 Physical Component Summary was 46.4 (10.8) in CHIK+ versus 49.1 (9.3) in CHIK- (p = 0.04). There was no significant difference between the two groups for the Mental Component Summary. CONCLUSIONS/SIGNIFICANCE: More than one year following the acute phase of infection, CHIK+ subjects reported more disabilities than those who were CHIK-. These persistent disabilities, however, have no significant influence on medical consumption, and the impact on quality of life is moderate.

Epidemiological studies have shown that mortality from malignant mesothelioma (MM) and lung cancer have increased with increasing cumulative exposure to asbestos. To investigate whether tumour-related biomarkers can contribute towards the evaluation of the carcinogenic risk in populations exposed to asbestos, the DNA adduct 8-hydroxy-2'-deoxyguanosine (80HdG), interleukine-6 (IL-6), platelet-derived growth factor (PDGF-BB), hepatocyte growth factor (HGF), basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGFbeta) and soluble mesothelin-related peptides (SMRPs) were analysed in a cohort of workers differently exposed to asbestos fibres at the workplace. To document biomarker levels in an unexposed population, 54 age-matched subjects were enrolled. A total of 119 subjects with a history of occupational exposure to asbestos underwent clinical examination and were interviewed by trained personnel, responding to a detailed questionnaire related to duration of asbestos exposure, smoking, and occupational task. According to the occupational tasks, asbestos-exposed subjects were analysed for their asbestos cumulative dose and the association with the biomarkers was evaluated. Among the occupational groups, maintenance workers, pipe fitters and electricians were exposed to a higher cumulative dose of asbestos fibres. Exposure to asbestos significantly increased the steady-state content of 80HdG in DNA. Elevated levels of 80HdG and IL-6 best reflected a high level of SMRPs, which is related to cell transformation. Subjects heavily exposed to asbestos [> 60(ff/cm3) x years] showed also a higher level of angiogenic factors. A combination of angiogenic biomarkers with a specific mesothelioma-biomarker such as SMRPs could be used for close surveillance of workers with a history of asbestos exposure.

The authors sought to determine levels of urinary cotinine and its association with collateral exposure to second-hand smoke in public health workers. Urinary cotinine was measured twice at 1-wk intervals in 28 public health workers or their spouses. Information on sources of second-hand smoke exposure and a dietary history were obtained from each participant. Geometric mean and median cotinine levels were 2.74 and 2.33 ng/mL, respectively. Only 6 instances of second-hand smoke exposure were reported from a combined 204 days of potential exposure, and these did not correspond to higher cotinine values. There was no association between consumption of foods containing nicotine and log-transformed urine cotinine levels (p = .80). The authors' analysis indicates dietary sources of nicotine are not important, even for persons with very low urinary cotinine levels. Further study is needed to determine sources of variation in urinary cotinine among largely unexposed populations.

The present paper reviews the American epidemic of West Nile Fever (WNF), which is the largest recorded outbreak ever. The epidemiological consequences of introducing a novel and immunologically unknown pathogen in a previously unexposed population and the possible evolution of a more pathogenic viral strain are discussed. In view of recent reports of imported cases in Denmark the issue of possible disease spread to Scandinavia is likewise addressed. However, the main scope of the article is to provide the clinician with an overview of the natural history, epidemiology and clinical characteristics of the disease.

The Blomia genus has been described as allergenic in man. The present study aimed to assess the prevalence of B. kulagini sensitization in a large population of allergic subjects without occupational exposure in a subtropical region (Canary Islands, Spain). Secondarily, a new standardized B. kulagini extract was evaluated. The study population comprised 207 patients. RAST for B. kulagini was positive in 76.2% of patients, and 47 of them were selected for the biologic standardization. When the prick test was performed with the nonstandardized extracts, results were positive in 76.6%, whereas when the test was repeated with the standardized extract, sensitivity rose to 95.7%. The conjunctival provocation test was positive in 78.3% of 46 evaluated patients. The bronchial provocation test was positive in 18 sensitized patients and negative in five controls. In conclusion, B. kulagini is an important cause of sensitization among the occupationally unexposed population of the studied area and should be included in allergy diagnostic tests. For reliable prick tests, the use of standardized extracts is mandatory.

We describe immunologic responses in subjects exposed to glutaraldehyde (GA) who were diagnosed as having occupational asthma, or who described work-related respiratory symptoms. A series of GA-modified proteins was characterized, and used to analyse sera from 20 GA-exposed workers and 21 unexposed workers for IgE antibodies. Inhibition studies were used to determine the specificity of binding. The reaction of GA with albumin in different molar ratios produced a range of modified proteins, which were used to measure specific IgE antibodies. A significant difference between exposed and unexposed subjects with serum IgE less than 150 kU/l could be detected for GA-specific IgE antibodies (P - 0.026), and 31% of exposed workers with occupational asthma had antibody levels greater than the unexposed population (mean +2.5 SD). False-positive results were obtained with serum from unexposed workers who had total IgE levels greater than 150 kU/l, but this binding was not inhibited by GA-modified proteins. We report the first evidence of immunologic sensitization in some workers exposed to GA. However, GA may behave like many other low-molecular-weight chemicals in that specific antibodies can be detected in only a small percentage of exposed workers who report work-related respiratory symptoms.

As part of a study on health effects of naphtha exposure, the association between naphtha exposure and urinary excretion of total protein, albumin, beta-N-acetyl-D-glucosaminidase (beta-NAG), and beta 2-microglobulin was assessed prospectively over 1 year among workers at an automotive plant that used naphtha to calibrate fuel injectors. Participants consisted of 248 workers who provided spot urine samples in June 1988 among whom 181 workers provided specimens again in June 1989. Naphtha air concentrations at the plant ranged from 6 to 790 mg/m3 and the length of exposure ranged from 0.8 to 7.3 years. In both 1988 and 1989, the overall distribution of the four measures of renal function appeared consistent with that of an unexposed population. In cross-sectional analyses, there were no statistically significant associations in the expected direction between cumulative or recent naphtha exposure and the measures of renal function. In longitudinal analyses, the change in beta-NAG was positively associated with the change in recent naphtha exposure (P = .009). The effect of the naphtha exposure during 1 workweek was assessed among 17 workers who provided urine samples Monday preshift, Monday postshift, and Friday postshift. No associations were found. The results of this study do not provide strong evidence of naphtha-associated renal effects at these levels of exposure.

The frequencies of HLA antigens in 27 patients with silicosis were compared with those of referents matched for exposure to silica dust, age, and sex, and having no roentgenographic signs of silicosis. A group of 900 blood donors served as an additional reference group. The prevalence of HLA-Aw19 was higher in the silicosis patients (29.6 percent) than in the silica-exposed referents (3.7 percent; p = 0.02). In turn, the frequency of Aw19 in the unexposed population consisting of blood donors (19.6 percent) was higher than that of silica-exposed referents (p = 0.04). Accepting that the prevalences of HLA antigens in the blood donors fairly well describe those of the silica-exposed population, the highest risk of developing advanced fibrosis was associated with the phenotypic combination Aw19,B18 (observed-expected ratio = 17.05; p less than 0.01). The results suggest that HLA-Aw19 and the haplotype Aw19,B18 are, at least in Finnish population, associated with a progression into advanced silicotic fibrosis.

An outbreak of leprosy in a previously unexposed population in Brugap village, in the Torricelli Mountains of eastern New Guinea is described. The outbreak conformed to the pattern of leprosy expected in a newly infected community, as described by Leiker. It resembled the Nauru epidemic in many respects. The prevalence rate was high in both sexes; childhood incidence was low, but adolescent incidence was high. Most patients had one or two tuberculoid lesions, and only 2 persons (3%) had lepromatous leprosy. Family and social factors were not important, probably because the overall incidence was so high as to submerge them, suggesting that the disease was highly infectious or the population very susceptible. Clinicopathological correlation was poor in typical tuberculoid cases, but good in others. Overall results of treatment were satisfactory, and no deformities or late neglected or concealed cases were found.

OBJECTIVES: The study attempts to define biological indicators of aluminium uptake and excretion in workers exposed to airborne aluminium compounds in a primary aluminium smelter. Also, this study defines the total and respirable aluminium dust fractions in two different potrooms, and correlates their concentrations with biological indicators in this group of workers. METHODS: Air was sampled at defined work sites. Non-destructive and conventional techniques were used to find total and respirable aluminium content of the dust. Blood and urine was collected from 84 volunteers employed at various work stations throughout the smelter and from two different cohorts of controls matched for sex, age, and socioeconomic status. Aluminium in serum samples and urine specimens was measured by flameless atomic absorption with a PE 4100 ZL spectrometer. RESULTS: The correlation of aluminium concentrations in serum and urine samples with the degree of exposure was assessed for three arbitrary exposure categories; low (0.036 mg Al/m3), medium (0.35 mg Al/m3) and high (1.47 mg Al/m3) as found in different areas of the smelter. At medium and high exposure, the ratio of respirable to total aluminium in the dust samples varied significantly. At high exposure, serum aluminium, although significantly raised, was still within the normal range of an unexposed population. The workers with low exposure excreted aluminium in urine at levels significantly higher than the controls, but still within the normal range of the population. However, potroom workers with medium and high exposure had significantly higher urinary aluminium than the normal range. CONCLUSIONS: It is concluded that only urinary aluminium constitutes a practical index of occupational exposure at or above 0.35 mg Al/m3, and that the respirable fraction of the dust may play a major role in the biological response to exposure to aluminium in a smelter environment.