PCB plasma level in different occupational groups in Iran.

Despite the ban of polychlorinated biphenyls (PCBs) some decades ago, concerns regarding their adverse health effects are continuing, because the workers employed for installation and repair of electrical equipment may be still exposed to PCBs. This study aimed to assess serum PCBs levels in workers in different industries. To do this, we determined the serum concentrations of 9 non-dioxin-like PCBs and 12 dioxin-like PCBs in 147 workers from seven occupational groups and 35 housewives. An electrical distribution company, paint manufacturer, and pesticide manufacturer were categorized as high probability exposure jobs, whereas turning and casting operations, polymer plastic manufacturing, professional driving, and office work were categorized as low probability exposure jobs. In addition, the average of PCB 138, 153, and 180 and PCB sums were observed to be significantly higher in paint manufacture workers compared to the another groups. In addition, the average PCB 118 level was higher in electrical distribution workers and housewives. Following the adjustment for age, blood lipid, residency place, and seafood in the regression model, the association of PCB 118 in electrical distribution workers and PCB 153 in paint manufacture workers remained significant. The results of this study served as further support for the hypothesis for an occupational basis for bioaccumulation of some PCB types. However, the plasma levels of almost all PCB congeners in Iran were found to be lower than many other countries.

Arsenic burden in e-waste recycling workers - A cross-sectional study at the Agbogbloshie e-waste recycling site, Ghana.

The export of e-waste from industrialized to developing countries has led to the formation of a large-scale informal e-waste recycling sector in Accra, Ghana. During recycling processes, workers are exposed to several hazardous substances, such as heavy metals. As a common component of e-waste, inorganic arsenic can be released during e-waste recycling processes. The aim of this study was to assess the exposure to inorganic arsenic species in e-waste workers compared to a control group. N = 84 e-waste workers and n = 94 control subjects were included in this analysis. Inorganic arsenic species were determined in urine samples using HPLC-ICP-MS. E-waste workers showed higher median concentrations of As(III), As(V), MMA, DMA and the sum of inorganic arsenic in comparison to the control group. More than 80% of the e-waste workers exceeded the acceptable concentration (14 µg/L), which was significantly higher in comparison to the control group (70%). The tolerable concentration (40 µg/L) was exceeded in 17.2% of the participants, meaning a statistically relevant risk of developing cancer due to arsenic exposure throughout their (working) life. In conclusion, the exposure to inorganic arsenic is not only a problem of informal e-waste recycling, but a major public health concern that needs further investigation.

Association of plasma levels of lipid and polychlorinated biphenyls in Iranian adult.

BACKGROUND: Exposure to Polychlorinated biphenyls (PCBs) continues over the world through seafood consumption and indoor exposure to building materials containing PCB. This study aimed to assess the relationship between plasma level of PCB congeners and lipid profile and Body Mass Index (BMI) as well. METHODS: The study population consisted of 181 Iranian adults. Data on BMI, plasma concentration of PCB congeners and serum level of lipid profile including Triglyceride, low-density lipoproteins and high-density lipoproteins, recruited from database of a project entitled "Occupational and environmental exposure to PCBs in Iran". Multiple linear regression analysis of associations between different quartiles of PCB congeners and various lipid fractions and BMI have been conducted. RESULTS: A linear increase in average serum Triglyceride and low-density lipoproteins (LDL) levels of participants in first, second, third and fourth quartiles of some PCB congeners was obtained. Following adjustment for age, gender, diet and other variables, only the association between different quartiles of PCB 138, PCB 153, PCB 118 and PCB sum and TG remained statistically significant. CONCLUSION: The study showed a significant positive relation between plasma PCBs concentrations and serum level of TG in the study population with normal PCBs levels.

Informal e-waste recycling and plasma levels of non-dioxin-like polychlorinated biphenyls (NDL-PCBs) - A cross-sectional study at Agbogbloshie, Ghana.

Informal e-waste recycling leads to a contamination of the workers with several hazardous substances, in particular heavy metals and persistent organic pollutants (POPs). Polychlorinated biphenyls (PCBs) belong to the group of POPs and are suspected to be associated with adverse health effects. In particular lower chlorinated PCBs, such as the congeners PCB 28 and PCB 52 are a marker of occupational exposure. The aim of our study was to assess the occupational PCB exposure in e-waste workers in relation to their specific recycling task (e.g. dismantling, burning). Altogether, n = 88 e-waste workers and n = 196 control subjects have been included in this study. All plasma participant's samples were evaluated for the PCB congeners PCB 28, 52, 101, 138, 153, 180 and sum of NDL-indicator congeners by human biomonitoring. A significant difference could be detected for the lower chlorinated PCB congeners (PCB 28, 52, and 101) for e-waste workers in comparison to the control group. Analyzing specific recycling tasks, workers who dismantle and those who burn e-waste showed the highest plasma levels of PCB 28 and 52. In conclusion, e-waste workers showed occupational related elevated PCB levels. Although those levels did not exceed the BAT value, workers were contaminated with PCBs during their task. Occupational health and safety measure are therefore necessary to protect the worker's health.

Spatiality in Health: The Distribution of Health Conditions Associated with Electronic Waste Processing Activities at Agbogbloshie, Accra.

Background: A walk through the Agbogbloshie e-waste recycling site shows a marked heterogeneity in the spatial distribution of the different e-waste processing activities, which are likely to drive clustering of health conditions associated with the different activity type in each space. Objective of study: To conduct a spatial assessment and analysis of health conditions associated with different e-waste activities at different activity spaces at Agbogbloshie. Methods: A choropleth showing the various activity spaces at the Agbogbloshie e-waste site was produced by mapping boundaries of these spaces using Etrex GPS device and individuals working in each activity spaces were recruited and studied. Upon obtaining consent and agreeing to participate in the study, each subject was physically examined and assessed various health outcomes of interest via direct physical examination while characterizing and enumerating the scars, lacerations, abrasions, skin condition and cuts after which both systolic and diastolic blood pressure values were recorded alongside the administration of open and close ended questionnaires. All individuals working within each activity space and consented to participate were recruited; giving a total of one hundred and twelve (112) subjects in all. Results: A study of the choropleth showed that health conditions associated e-waste processing activities were clustered in a fashion similar to the corresponding distribution of each activity. While a total of 96.2% of all the study subjects had cuts, the dismantlers had higher mix of scars, lacerations and abrasions. Abrasions were observed in 16.3% of the dismantlers. Scars were the most common skin condition and were observed on the skins of 93.6% of the subjects. Prevalence of burns among the study subjects was 23.1%. Developing hypertension was not associated with activity type and while a total of 90.2% of subjects had normal blood pressure and 9.8% of them were hypertensives. Finally, 98.2% of respondents felt the need to have a first aid clinic at the site with 96.4% and 97.3% willing to visit the clinic and pay for services respectively. Conclusion: We conclude that while the observed injuries were random and were due purely to accidents without any role of spatial determinants such as the configuration, slope, topography and other subterranean features of the activity spaces, a strong association between the injuries and activity type was observed.

Health Consequences for E-Waste Workers and Bystanders-A Comparative Cross-Sectional Study.

Informal e-waste recycling is associated with several health hazards. Thus far, the main focus of research in the e-waste sector has been to assess the exposure site, such as the burden of heavy metals or organic pollutants. The aim of this study was to comprehensively assess the health consequences associated with informal e-waste recycling. A questionnaire-based assessment regarding occupational information, medical history, and current symptoms and complaints was carried out with a group of n = 84 e-waste workers and compared to a control cohort of n = 94 bystanders at the e-waste recycling site Agbogbloshie. E-waste workers suffered significantly more from work-related injuries, back pain, and red itchy eyes in comparison to the control group. In addition, regular drug use was more common in e-waste workers (25% vs. 6.4%). Both groups showed a noticeable high use of pain killers (all workers 79%). The higher frequency of symptoms in the e-waste group can be explained by the specific recycling tasks, such as burning or dismantling. However, the report also indicates that adverse health effects apply frequently to the control group. Occupational safety trainings and the provision of personal protection equipment are needed for all workers.

Are the knowledge of non-malignant asbestos-related diseases and lung function impairment differentially associated with psychological well-being? A cross-sectional study in formerly asbestos-exposed workers in Germany.

OBJECTIVES: The knowledge of past asbestos exposure may lead to chronic psychological strain. In addition, the information about an increased cancer risk can place a psychological burden on individuals triggering mental health symptoms of depression or anxiety. This applies in particular to individuals with non-malignant asbestos-related disease (ARD) such as lung fibrosis and pleural thickening with or without lung function impairment. ARDs with or without lung function impairment may develop even years after exposure cessation. Therefore, the aim of the present study was to test for our cohort whether non-malignant ARD and lung function impairment have differential effects on mental health and psychological strain. DESIGN: Cross-sectional study. PARTICIPANTS AND SETTING: Overall, 612 male participants (mean age=66.2 years, SD=9.5) attending a surveillance programme for ARDs received routine examinations including lung function testing (24% refused to fill in the psychological questionnaire) at a German university hospital study centre from August 2008 to August 2013. OUTCOME MEASURES: Using multiple hierarchical regression analysis, ARD diagnosis and lung function impairment were used to predict psychological health as measured with validated questionnaires for depression and anxiety. Psychological strain was operationalised by intrusive thoughts and specific fear of cancer. RESULTS: The strongest predictor for mental health was obstructive functional impairment (eg, anxiety: ß=0.22, p<0.001). Psychological strain was predicted by the presence of a non-malignant ARD (eg, intrusive thoughts: ß=0.17, p=0.003). CONCLUSIONS: The presence of mental health symptoms is associated with ventilation disturbances, whereas the knowledge of an already initiated morphological change-caused by asbestos exposure-is primarily associated with psychological strain. Specifically, the affected individuals are more prone to intrusive thoughts and specific fear of asbestos-related cancer. As an implication, physicians should be sensitised about possible consequences of risk communication and functional impairment to counteract excessive fear or anxiety.

Association of plasma PCB levels and HbA1c concentration in Iran.

BACKGROUND: The rapid increase in prevalence of diabetes mellitus over the last decades warrants more attention to the effects of environmental and occupational exposures on glucose metabolism. Our study aimed to assess the association between the plasma levels of various congeners of polychlorinated biphenyls (PCBs) and the serum concentration of glycated haemoglobin (HbA1c). METHODS: Our study population consisted of 140 Iranian adults from seven different occupational groups and a group of non-occupationally exposed female participants. The plasma concentration of PCBs were determined at the laboratory of occupational toxicology at RWTH Aachen University, Germany. We considered an HbA1c concentration of 5.7% and more as indicating a disturbed glucose metabolism. Logistic regression was used to assess the association between quartiles of concentrations of PCB congeners and serum HbA1c. RESULTS: Participants with an increased HbA1c value had higher plasma levels of PCB 138, 153, 180 and the PCB sum, although this association was statistically not significant. There was no significant difference between the levels of PCB 138, 153, 180, the sum of these congeners, and PCB 118 in their quartiles when comparing with HbA1c concentrations. CONCLUSIONS: For our cohort, we could not demonstrate a significant association between PCB and HbA1c concentrations indicating a disturbance of glucose metabolism.

Migrating pleural plaque in a patient with asbestos induced pleural disease: a case report.

BACKGROUND: Health surveillance of formerly asbestos exposed individuals focus on early detection of asbestos related diseases, such as lung fibrosis (asbestosis), pleural plaques, mesothelioma and lung cancer in particular. One main concern is the early and clear identification of lesions with a high risk of malignant changes and their undelayed clinical work-up. False positive results may lead to unnecessary and often painful diagnostic interventions, which create high costs when applied to a large cohort and also may discredit the whole program. We describe an unusual presentation of a common lesion among asbestos exposed individuals, which has to our knowledge never been described before. Being aware of this pathological pathway may prevent inadequate clinical decisions with disadvantages for the patient. Underlying implications regarding health surveillance and the reading of CT-scans of the thorax are important for the management of formerly asbestos exposed individuals. CASE PRESENTATION: During follow-up of an asbestos exposed 72 year old former power plant worker with known pleural changes, a nodule located next to the left costophrenic angle was newly discovered on CT-scan. As the previous scan 1 year before did not show any changes in that area, a fast growing tumour was suspected and an immediate biopsy performed. The tissue showed the characteristics of a pleural plaque with no signs of malignancy. After carefully reviewing all previous radiographs a rounded opacity attached to the mediastinal pleura close to the oesophagus and slightly cranial to the position of the removed nodule could be discerned. That nodule had increased in size over several years and was no longer visible on the latest scan. It appeared that the originally slow growing plaque had migrated to the costophrenic angle some time before it was discovered in the latest scan thus imposing as a fast growing tumour. CONCLUSIONS: We concluded that asbestos related pleural plaques can under special circumstances get separated from the pleura and migrate to another position in the pleural cavity. The case provides new insights in the development and properties of pleural lesions and may offer new options for the management of formerly asbestos exposed patients.

Lung function not affected by asbestos exposure in workers with normal Computed Tomography scan.

BACKGROUND: It has been suggested that asbestos exposure affects lung function, even in the absence of asbestos-related pulmonary interstitial or pleural changes or emphysema. METHODS: We analyzed associations between well-known asbestos-related risk factors, such as individual cumulative asbestos exposure, and key lung function parameters in formerly asbestos-exposed power industry workers (N = 207) with normal CT scans. For this, we excluded participants with emphysema, fibrosis, pleural changes, or any combination of these. RESULTS: The lung function parameters of FVC, FEV1, DLCO/VA, and airway resistance were significantly associated with the burden of smoking, BMI and years since end of exposure (only DLCO/VA). However, they were not affected by factors directly related to amount (eg, cumulative exposure) or duration of asbestos exposure. CONCLUSIONS: Our results confirm the well-known correlation between lung function, smoking habits, and BMI. However, we found no significant association between lung function and asbestos exposure.

Radiological surveillance of formerly asbestos-exposed power industry workers: rates and risk factors of benign changes on chest X-ray and MDCT.

BACKGROUND: To determine the prevalence of asbestos-related changes on chest X-ray (CXR) and low-dose multidetector-row CT (MDCT) of the thorax in a cohort of formerly asbestos-exposed power industry workers and to assess the importance of common risk factors associated with specific radiological changes. METHODS: To assess the influence of selected risk factors (age, time since first exposure, exposure duration, cumulative exposure and pack years) on typical asbestos-related radiographic changes, we employed multiple logistic regression and receiver operating characteristic (ROC) analysis. RESULTS: On CXR, pleural changes and asbestosis were strongly associated with age, years since first exposure and exposure duration. The MDCT results showed an association between asbestosis and age and between plaques and exposure duration, years since first exposure and cumulative exposure. Parenchymal changes on CXR and MDCT, and diffuse pleural thickening on CXR were both associated with smoking. Using a cut-off of 55 years for age, 17 years for exposure duration and 28 years for latency, benign radiological changes in the cohort with CXR could be predicted with a sensitivity of 82.0% for all of the three variables and a specificity of 47.4%, 39.0% and 40.6%, respectively. CONCLUSIONS: Participants aged 55 years and older and those with an asbestos exposure of at least 17 years or 28 years since first exposure should be seen as having an increased risk of abnormal radiological findings. For implementing a more focused approach the routine use of low-dose MDCT rather than CXR at least for initial examinations would be justified.

Is it useful to combine sputum cytology and low-dose spiral computed tomography for early detection of lung cancer in formerly asbestos-exposed power industry workers?

BACKGROUND: Low-dose spiral computed tomography (LDSCT) in comparison to conventional chest X-ray proved to be a highly sensitive method of diagnosing early stage lung cancer. However, centrally located early stage lung tumours remain a diagnostic challenge. We determined the practicability and efficacy of early detection of lung cancer when combining LDSCT and sputum cytology. METHODS: Of a cohort of 4446 formerly asbestos exposed power industry workers, we examined a subgroup of 187 (4.2%) high risk participants for lung cancer at least once with both LDSCT and sputum cytology. After the examination period the participants were followed-up for more than three years. RESULTS: The examinations resulted in the diagnosis of lung cancer in 12 participants (6.4%). Six were in clinical stage I. We found 10 non-small cell lung carcinomas and one small cell lung carcinoma. Sputum specimens showed suspicious pathological findings in seven cases and in 11 cases the results of LDSCT indicated malignancies. The overall sensitivity and specificity of sputum cytology was 58.0% and 98% with positive (PPV) and negative (NPV) predictive values of 70% and 97%. For LDSCT we calculated the sensitivity and specificity of 92% and 97%. The PPV and NPV were 65% and 99% respectively. CONCLUSIONS: Our results confirmed that in surveillance programmes a combination of sputum cytology and LDSCT is well feasible and accepted by the participants. Sputum examination alone is not effective enough for the detection of lung cancer, especially at early stage. Even in well- defined risk groups highly exposed to asbestos, we cannot recommend the use of combined LDSCT and sputum cytology examinations as long as no survival benefit has been proved for the combination of both methods. For ensuring low rates of false-positive and false-negative results, programme planners must closely cooperate with experienced medical practitioners and pathologists in a well-functioning interdisciplinary network.

Changes of mesothelin and osteopontin levels over time in formerly asbestos-exposed power industry workers.

PURPOSE: In patients developing malignant pleural mesothelioma (MPM) or lung cancer, using effective tumour markers is the quickest way to ensure early diagnosis and improve survival time. The aim of our study was to assess the influence of age and asbestos exposure on the blood levels of the proposed tumour markers, mesothelin and osteopontin, and to determine the change of these markers over time. METHODS: We analysed 3,329 blood samples of 2,262 participants including 1,894 formerly asbestos-exposed power industry workers, a mixed group of 266 participants with an unknown history of asbestos exposure and a group of 102 non-asbestos-exposed controls. Marker concentrations were determined using commercial ELISA kits. RESULTS: While age had a strong influence on marker levels, there was no association between exposure duration or benign asbestos-related disease and marker levels. In order to assess the maximum increase that can be expected to occur in asbestos-exposed workers those with an at least 10 % increase were selected (n = 290 for mesothelin and n = 81 for osteopontin). The 95th percentile of the annual change was 0.402 nmol/l for mesothelin and 334 ng/ml for osteopontin. In two patients with MPM and five with lung cancer, we could obtain more than one marker result before the diagnosis was made. Both MPM patients showed a steep increase of mesothelin levels. CONCLUSIONS: Fixed cut-off values for deciding between intensive clinical work-up and continued surveillance appeared inadequate for the evaluated markers. While general conclusions cannot be drawn, we can say that the results of the two patients would be consistent with a mesothelin increase between 6 and 18 months before clinical symptoms developed.

Non-response bias in a surveillance program for asbestos-related lung cancer.

OBJECTIVES: In a cohort study non-response might lead to a biased selection of cohort members and may affect the validity and reliability of the study outcome. To detect the possible effects of a non-response bias on study results, we evaluated the reasons for non-participation and the differences of respondents and non-respondents in a health surveillance program for power industry workers, formerly exposed to asbestos. METHODS: A cohort of former power plant workers was formed to participate in an early detection program for lung cancer. We evaluated the results of 1,019 individuals (mean age 66 yr), of which 839 took part in at least one examination, 180 refused to participate or did not respond. To obtain the reasons for non-response, we interviewed the cohort members by telephone or we requested them by mail to complete and return a brief questionnaire. Further sources of information were the communal registration offices and local health offices. RESULTS: The main reasons for non-participation were refusal (35%), illness (23.3%), death (16.7%) and difficulties with traveling (13.3%). It was impossible to make contact with or obtain an explanation from 11.7%. In a logistic regression model we demonstrated that advanced age and a long travel distance from the study center negatively affected the participation rate (p<0.001). There was no difference between respondents and non-respondents regarding prevalence (p=0.559) and incidence of lung cancer (p=0.882). CONCLUSION: We concluded that in our cohort non-participation did not cause a selection bias in terms of lung cancer rates.

Retrospective exposure assessment to airborne asbestos among power industry workers.

BACKGROUND: A method of individually assessing former exposure to asbestos fibres is a precondition of risk-differentiated health surveillance. The main aims of our study were to assess former levels of airborne asbestos exposure in the power industry in Germany and to propose a basic strategy for health surveillance and the early detection of asbestos related diseases. METHODS: Between March 2002 and the end of 2006, we conducted a retrospective questionnaire based survey of occupational tasks and exposures with airborne asbestos fibres in a cohort of 8632 formerly asbestos exposed power industry workers. The data on exposure and occupation were entered into a specially designed computer programme, based on ambient monitoring of airborne asbestos fibre concentrations. The cumulative asbestos exposure was expressed as the product of the eight-hour time weighted average and the total duration of exposure in fibre years (fibres/cubic centimetre-years). RESULTS: Data of 7775 (90% of the total) participants working in installations for power generation, power distribution or gas supply could be evaluated. The power generation group (n = 5284) had a mean age of 56 years, were exposed for 20 years and had an average cumulative asbestos exposure of 42 fibre years. The occupational group of "metalworkers" (n = 1600) had the highest mean value of 79 fibre years. The corresponding results for the power distribution group (n = 2491) were a mean age of 45 years, a mean exposure duration of 12 years and an average cumulative asbestos exposure of only 2.5 fibre years. The gas supply workers (n = 512) had a mean age of 54 years and a mean duration of exposure of 15 years. CONCLUSIONS: While the surveyed cohort as a whole was heavily exposed to asbestos dust, the power distribution group had a mean cumulative exposure of only 6% of that found in the power generation group. Based on the presented data, risk-differentiated disease surveillance focusing on metalworkers and electricians from the power generating industry seems justified. That combined with a sensitive examination technique would allow detecting asbestos related diseases early and efficiently.

Asbestos Surveillance Program Aachen (ASPA): initial results from baseline screening for lung cancer in asbestos-exposed high-risk individuals using low-dose multidetector-row CT.

The purpose of this study was to assess the prevalence of lung cancer in a high-risk asbestos-exposed cohort using low-dose MDCT. Of a population of 5,389 former power-plant workers, 316 were characterized as individuals at highest risk for lung cancer according to a lung-cancer risk model including age, asbestos exposure and smoking habits. Of these 316, 187 (mean age: 66.6 years) individuals were included in a prospective trial. Mean asbestos exposure time was 29.65 years and 89% were smokers. Screening was performed on a 16-slice MDCT (Siemens) with low-dose technique (10/20 mAs(eff.); 1 mm/0.5 mm increment). In addition to soft copy PACS reading analysis on a workstation with a dedicated lung analysis software (LungCARE; Siemens) was performed. One strongly suspicious mass and eight cases of histologically proven lung cancer were found plus 491 additional pulmonary nodules (average volume: 40.72 ml, average diameter 4.62 mm). Asbestos-related changes (pleural plaques, fibrosis) were visible in 80 individuals. Lung cancer screening in this high-risk cohort showed a prevalence of lung cancer of 4.28% (8/187) at baseline screening with an additional large number of indeterminate pulmonary nodules. Low-dose MDCT proved to be feasible in this highly selected population.