Lung Cancer Mortality and Styrene Exposure in the Reinforced-Plastics Boatbuilding Industry: Evaluation of Healthy Worker Survivor Bias.

The evidence for styrene's being a human lung carcinogen has been inconclusive. Occupational cohorts within the reinforced-plastics industry are an ideal population in which to study this association because of their relatively high levels of exposure to styrene and lack of concomitant exposures to other known carcinogens. However, healthy worker survivor bias (HWSB), where healthier workers stay employed longer and thus have higher exposure potential, is a likely source of confounding bias for exposure-response associations, in part due to styrene's acute effects. Through December 31, 2016, we studied a cohort of 5,163 boatbuilders exposed to styrene in Washington State who were employed between 1959 and 1978; prior regression analyses had demonstrated little evidence for an exposure-response relationship between styrene exposure and lung cancer mortality. Based on estimates of necessary components of HWSB, we found evidence for a potentially large HWSB. Using g-estimation of a structural nested model to account for HWSB, we estimated that 1 year of styrene exposure at more than 30 parts per million accelerated time to lung cancer death by 2.29 years (95% confidence interval: 1.53, 2.94). Our results suggest possibly strong HWSB in our small cohort and indicate that large, influential studies of styrene-exposed workers may suffer from similar biases, warranting a reassessment of the evidence of long-term health effects of styrene exposure.

Manufacturing Industry Cancer Risk in Japan: A Multicenter Hospital-Based Case Control Study.

BACKGROUND: It is well known that specific occupations can cause harm in developing malignant neoplasms. Chemical exposure is particularly high in the manufacturing industry and workers in this sector may face a higher occupational risk for cancer. We aimed to estimate inequalities in the risk of cancers related to occupational chemical exposure in various manufacturing categories. METHODS: Using nationwide clinical inpatient data (1984-2017) in Japan, we undertook a multicenter, case-control study with regard to risks of developing cancers among various manufacturing industry categories. Using the food manufacturing industry as the reference group, odds ratios and 95% confidence intervals for each industry were estimated by conditional logistic regression, adjusted for sex, age, admission period, and the admitting hospital. Medical record summaries accounting for 89% of industrial categories with high odds ratios were collected to confirm diagnoses made on the basis of histology. We estimated industrial hazards based on the Pollutant Release and Transfer Register. RESULTS: A reduced risk for some of common cancers was observed among lumber and wood products industries. Leather tanning, leather products and fur tended to show a higher risk: 2.36 (95% CI 1.15-4.83) for pancreatic cancer, 2.85 (95% CI 1.26-6.47) for liver cancer and 2.00 (95% CI 1.01-3.99) for lung cancer. For the electronics category, observations of high risk ranged from 2.09 (95%CI 1.18-3.70) for ureter cancer, to 2.49 (95% CI 1.79-3.55) for kidney cancer. CONCLUSIONS: This study revealed industry risk inequalities in manufacturing categories were present with regard to the risk of common cancers in Japan.

Effect of work-related factors on the prevalence of peptic ulcer disease among Korean workers: a nationwide population-based study.

BACKGROUND: Working environment such as psychosocial factors impacts the health of workers. However, few studies have assessed the association of work-related factors with the prevalence of peptic ulcer disease (PUD) in large population based study. METHODS: After exclusion of military personnel, 16,099 wage workers (20 ≤ age ≤ 65 years) from the Fourth Korea National Health and Nutrition Examination Survey (2008-2011) were included in this study. Job status was defined as the place of employment of longest duration. To evaluate the working environment, we used a comprehensive work-stressor measure. Univariate and multivariable regression analyses were performed to assess the effect of occupation type on the prevalence of PUD. RESULTS: Among the subjects, 5540, 3398, and 7161 were white-, pink-, and blue-collar workers, respectively. The prevalence of PUD was highest among blue-collar workers (n = 336, 7.1%), followed by pink-collar (n = 116, 5.1%) and white-collar (n = 180, 4.9%) workers. In the multivariable analysis, work type and uncomfortable gestures were independently associated with the risk of PUD. Compared with office workers, operators in industrial plants and machine operators had a significantly higher prevalence of PUD (odds ratio, 1.9; 95% confidence interval, 1.1-3.3) after adjusting for age, socioeconomic factors, sex, smoking, alcohol consumption, daily exercise, sleep duration, and working conditions. DISCUSSION: In conclusion, work-related factors, particularly blue-collar work and uncomfortable job gestures, are independently associated with the risk of PUD. Therefore, it is important to monitor the development of PUD in workers exposed to these factors.

12-year data on skin diseases in the Finnish Register of Occupational Diseases II: Risk occupations with special reference to allergic contact dermatitis.

BACKGROUND: Detailed epidemiological studies on occupational skin diseases (OSDs) are scarce. OBJECTIVES: To analyze risk occupations for OSDs in the Finnish Register of Occupational Diseases (FROD). METHODS: We retrieved numbers of OSD cases (excluding skin infections) for different occupations from the FROD in 2005-2016. In the FROD, Finnish ISCO-08-based classification of occupations was used since 2011, and the preceding ISCO-88-based version until 2010. We combined cases from the earlier and the later period using conversion tables provided by Statistics Finland. We included occupations with at least five cases and analyzed them in detail. We calculated incidence rates for OSDs and separately for allergic contact dermatitis (ACD) in different risk occupations using national labor force statistics. We also studied causes of ACD in these occupations. RESULTS: Risk occupations with the largest number of OSD cases included farmers, hairdressers, assistant nurses, cooks, cleaners, machinists, and nurses. Occupations with the highest incidences of OSDs comprised spray painters (23.8/10 000 person years), bakers (20.4), and dental technicians (19.0). Epoxy compounds and acrylates were prominent causes of ACD in occupations with the highest incidences of ACD. CONCLUSIONS: Uniform use of International Standard Classification of Occupations (ISCO) would facilitate comparisons of OSD figures in different countries.

Occupational noise exposure: A review of its effects, epidemiology, and impact with recommendations for reducing its burden.

Exposure to hazardous noise is one of the most common occupational risks, both in the U.S. and worldwide. Repeated overexposure to noise at or above 85 dBA can cause permanent hearing loss, tinnitus, and difficulty understanding speech in noise. It is also associated with cardiovascular disease, depression, balance problems, and lower income. About 22 million U.S. workers are currently exposed to hazardous occupational noise. Approximately 33% of working-age adults with a history of occupational noise exposure have audiometric evidence of noise-induced hearing damage, and 16% of noise-exposed workers have material hearing impairment. While the Mining, Construction, and Manufacturing sectors typically have the highest prevalence of noise exposure and hearing loss, there are noise-exposed workers in every sector and every sector has workers with hearing loss. Noise-induced hearing loss is preventable. Increased understanding of the biological processes underlying noise damage may lead to protective pharmacologic or genetic therapies. For now, an integrated public health approach that (1) emphasizes noise control over reliance on hearing protection, (2) illustrates the full impact of hearing loss on quality of life, and (3) challenges the cultural acceptance of loud noise can substantially reduce the impact of noise on worker health.

Semiconductor Work and Adverse Pregnancy Outcomes Associated with Male Workers: A Retrospective Cohort Study.

OBJECTIVES: A hazardous work environment in semiconductor factories is a threat to the workers' health. Semiconductor manufacturing characteristically requires young workers, and reproductive toxicity is an important issue. Studies investigating reproductive toxicity among individuals working in the semiconductor manufacturing industry have primarily focused on outcomes in women. Information on the reproductive health of male semiconductor factory workers is limited. This study aimed to evaluate the association between workplace exposures among male workers in a Korean semiconductor company and adverse pregnancy outcomes. METHODS: Based on the data from the 2015 Semiconductor Health Survey (SHS), which evaluated the workplace exposures, pregnancy outcomes, and general health of 21 969 employees of the semiconductor industry in South Korea, we included 3868 male workers with 7504 pregnancy outcomes identified by self-reports for this retrospective cohort study. Data regarding the pregnancy outcomes, order of pregnancy, and the years of the outcomes were collected via the SHS questionnaire. Adverse pregnancy outcomes were defined as preterm labor, spontaneous abortion, and stillbirth. Workplace exposures were classified as fabrication, assembly, others, lab, and office work (reference group). A generalized estimating equations model including repeated events of individuals and producing relative risk (RR) and 95% confidence interval (CI) was used to estimate the association between workplace exposure and adverse pregnancy outcomes. Analyses were adjusted for work location, spouse's employment in semiconductor production work, educational level, marital status, risky alcohol drinking, smoking status, body mass index, order of pregnancy, and age and year of pregnancy outcome, which were based on a priori decisions. RESULTS: The adjusted risk for adverse outcomes was higher [RR (95% CI): 1.47 (1.04, 2.07)] among assembly process workers compared with the office workers. Adjusted risks for adverse outcomes among workers in assembly and fabrication, whose spouses also worked in semiconductor production, were 1.60 (95% CI: 1.04, 2.46) and 1.74 (95% CI: 1.18, 2.57) times higher, respectively, compared with the office workers with spouses not working in semiconductor production. CONCLUSIONS: Based on these findings, semiconductor work might be considered a risk factor for reproductive toxicity among male workers, especially for those whose spouses have the same job.

Mortality Among Men and Women in the North American Synthetic Rubber Industry, 1943 to 2009.

OBJECTIVE: To evaluate 1943 to 2009 mortality among 22,785 synthetic rubber industry employees. METHODS: Standardized mortality ratio (SMR) and internal Cox regression analyses. RESULTS: Among hourly employees with more than or equal to 10 years worked and more than or equal to 20 years since hire, SMRs were elevated for leukemia (SMR = 139, 95% confidence interval [CI] = 106 to 179), non-Hodgkin lymphoma (NHL) (SMR = 136, CI = 102 to 177), bladder cancer (SMR = 148, CI = 110 to 195) and, for women only, lung cancer (SMR = 225, CI = 103 to 427). Butadiene and styrene exposure-response trends were positive for leukemia and bladder cancer but not for NHL or for lung cancer among women. CONCLUSIONS: Results support a causal relationship between butadiene and leukemia. Interpretation of results for lung cancer among women and for bladder cancer is uncertain because of inability to control for smoking and inadequate or inconsistent support from other studies for an association between butadiene or styrene and the latter cancers.

Gender, Depression, and Blue-collar Work: A Retrospective Cohort Study of US Aluminum Manufacturers.

BACKGROUND: Industrial blue-collar workers face multiple work-related stressors, but evidence regarding the burden of mental illness among today's blue-collar men and women remains limited. METHODS: In this retrospective cohort study, we examined health and employment records for 37,183 blue- and white-collar workers employed by a single US aluminum manufacturer from 2003 to 2013. Using Cox proportional hazards regression, we modeled time to first episode of treated depression by gender and occupational class. Among cases, we modeled rates of depression-related service utilization with generalized gamma regression. RESULTS: Compared with their white-collar counterparts, blue-collar men were more likely to be treated for depression (hazard ratio [HR] = 1.3; 95% confidence interval [CI] = 1.1, 1.4) as were blue-collar women (HR = 1.4; 1.2, 1.6). Blue-collar women were most likely to be treated for depression as compared with white-collar men (HR = 3.2; 95% CI = 2.1, 5.0). However, blue-collar workers used depression-related services less frequently than their white-collar counterparts among both men (rate ratio = 0.91; 95% CI = 0.84, 0.98) and women (rate ratio = 0.82; 95% CI = 0.77, 0.88). CONCLUSIONS: Blue-collar women were more likely to be treated for depression than white-collar workers, and blue-collar women were most likely to be treated for depression compared with white-collar men. However, blue-collar men and women used depression-related healthcare services less frequently than white-collar workers. These findings underscore that blue-collar women may be uniquely susceptible to depression, and suggest that blue-collar workers may encounter barriers to care-seeking related mental illness other than their insurance status.

Mortality among United States aerospace materials manufacturing workers.

OBJECTIVES: To evaluate long-term mortality rates among aerospace material manufacturing workers as follow-up to an earlier observed excess of nephritis/nephrosis. METHODS: Subjects were 2020 workers ever employed in the facility during 1963-2014. Vital status through 2014 was determined for all subjects and cause of death for 99.2% of 492 deaths. We computed standard mortality ratios (SMR) and internal relative risks. RESULTS: SMRs for nephritis/nephrosis were unremarkable. We observed statistically significant elevated SMRs for kidney cancer among all workers and for the category "other lymphatic hematopoietic tissue cancer" (4/5 deaths from multiple myeloma) among long-term workers with potential plant exposure. CONCLUSIONS: We found no evidence of elevated mortality rates for nephritis/nephrosis. Study limitations precluded robust evaluation of whether the elevated rates for kidney cancer and other lymphatic hematopoietic tissue cancer were related to occupational factors at the study site. Our findings for these two cancers warrant continued mortality follow-up.

Relationship Between Nicotine Dependency and Occupational Injury in a Japanese Large-Scale Manufacturing Enterprise: A Single-Center Study.

OBJECTIVES: Although several studies have shown the association between smoking and occupational injury, the exact mechanism by which smoking contributes to occupational injury remains unclear. We conducted a 5-year case-control study in a population of Japanese large-scale enterprise workers aimed to verify the hypothesis that nicotine dependency is positively associated with occupational injury. METHODS: A total of 3179 to 3574 male workers annually participated in this study conducted from 2008 to 2012. Employees who had an occupational injury as detailed in the company records were included in the case group, while employees who did not have any occupational injury were included in the control group. Information on smoking status, nicotine dependency [assessed according to time to first cigarette (TTF) and cigarette per day (CPD)], and potential confounders were obtained via questionnaires administered during periodic health checkups. Odds ratios (ORs) were estimated via multiple logistic regression analysis and integrated using the general variance-based fixed effects model. RESULTS: The overall adjusted OR of occupational injury in smokers was 1.71 [95% confidence interval (95% CI): 1.10 to 2.66]. The OR for low and high nicotine dependency according to TTF was 1.52 (95% CI: 0.92 to 2.51) and 1.98 (95% CI: 1.15 to 3.41), respectively. CONCLUSION: Nicotine dependency was related to an increased risk of occupational injury. These findings support the hypothesis that smoking is associated with occupational injury.

British rubber and cable industry cohort: 49-year mortality follow-up.

BACKGROUND: The International Agency for Research on Cancer (IARC) has determined there is sufficient evidence that working in the rubber manufacturing industry increases the risk of cancers of the stomach, lung, bladder and leukaemia and lymphoma. OBJECTIVES: To examine mortality patterns of a prospective cohort of men from the rubber and cable manufacturing industries in Great Britain. METHODS: SMRs were calculated for males aged 35+ years at start of follow-up in 1967-2015 using the population of England and Wales as the external comparator. Tests for homogeneity and trends in SMRs were also completed. RESULTS: For all causes, all malignant neoplasms, non-malignant respiratory diseases and circulatory diseases, SMRs were significantly elevated, and also particularly for cancers of the stomach (SMR=1.26,95% CI 1.18 to 1.36), lung (1.25,95% CI 1.21 to 1.29) and bladder (1.16,95% CI 1.05 to 1.28). However, the observed deaths for leukaemia, non-Hodgkin's lymphoma (NHL) and multiple myeloma were as expected. Bladder cancer risks were elevated only in workers exposed to antioxidants containing 1-naphthylamine and 2-naphthylamine. CONCLUSIONS: This study provides evidence of excess risks in the rubber industry for some non-cancer diseases and supports IARC's conclusions in relation to risks for cancers of the bladder, lung and stomach, but not for leukaemia, NHL or multiple myeloma.

An Occupational Legacy: Malignant Mesothelioma Incidence and Mortality in Wisconsin.

OBJECTIVES: The aim of the study was to describe mesothelioma occurrence in Wisconsin from 1997 to 2013 by usual industry and occupation (I&O), including occupations generally considered low risk. METHODS: Population-based rates and standardized incidence and mortality ratios were calculated. Two case-control analyses were designed to compare mesothelioma incidence and mortality in specific I&O groups with occurrence of (1) brain and central nervous system cancers and (2) other causes of death, using logistic regression. RESULTS: Mesothelioma incidence and mortality were elevated in Wisconsin (SIRadj = 1.20 [1.13 to 1.28]; SMRadj = 1.30 [1.22 to 1.38]). Certain industry (construction, manufacturing) and occupation (construction and extraction) groups were associated with increased odds of mesothelioma, with some evidence of increased risk among teachers. CONCLUSIONS: Forty years after the Occupational and Safety Health Act, mesothelioma incidence and mortality remain elevated in Wisconsin, with increased risk continuing for certain I&O groups.

Occupational and Take-home Lead Exposure Among Lead Oxide Manufacturing Employees, North Carolina, 2016.

OBJECTIVE: In 2016, North Carolina blood lead level (BLL) surveillance activities identified elevated BLLs among 3 children exposed to take-home lead by household members employed at a lead oxide manufacturing facility. We characterized BLLs among employees and associated children and identified risk factors for occupational and take-home lead exposure. METHODS: We reviewed BLL surveillance data for 2012-2016 to identify facility employees and associated children. We considered a BLL ≥5 µg/dL elevated for adults and children and compared adult BLLs with regulatory limits and recommended health-based thresholds. We also conducted an environmental investigation and interviewed current employees about exposure controls and cleanup procedures. RESULTS: During 2012-2016, 5 children associated with facility employees had a confirmed BLL ≥5 µg/dL. Among 77 people employed during 2012-2016, median BLLs increased from 22 µg/dL (range, 4-45 µg/dL) in 2012 to 37 µg/dL (range, 16-54 µg/dL) in 2016. All employee BLLs were <60 µg/dL, the national regulatory threshold for immediate medical removal from lead exposure; however, 55 (71%) had a BLL ≥20 µg/dL, a recommended health-based threshold for removal from lead exposure. Because of inadequate controls in the facility, areas considered clean were visibly contaminated with lead dust. Employees reported bringing personal items to work and then into their cars and homes, resulting in take-home lead exposure. CONCLUSIONS: Integration of child and adult BLL surveillance activities identified an occupational source of lead exposure among workers and associated children. Our findings support recent recommendations that implementation of updated lead standards will support better control of lead in the workplace and prevent lead from being carried home.

Respirator use and its impact on particulate matter exposure in aluminum manufacturing facilities.

Objectives As part of a large epidemiologic study of particulate health effect, this study aimed to report respirator use among total particulate matter (TPM) samples collected in a major aluminum manufacturing company from 1966‒2013 and evaluate the impact of respirator-use adjustment on exposure estimation. Methods Descriptive analyses were performed to evaluate respirator use across facilities and by facility type and job. Protection factors were applied to TPM measurements for recorded respirator use. Estimated TPM exposure for each job ‒ before and after respirator-use adjustment ‒ were compared to assess the impact of adjustment on exposure estimation. Results Respirator use was noted for 37% of 12 402 full-shift personal TPM samples. Measured TPM concentration ranged from less than detectable to 8220 mg/m3, with arithmetic mean, median and standard deviation being 10.6, 0.87 and 130 mg/m 3, respectively. Respirators were used more often in smelting facilities (52% of TPM measurements) than in fabricating (17%) or refinery facilities (28%) (P<0.01). Sixty-two percent of jobs in smelting facilities were subject to respirator-use adjustment, whereas it was 20% and 70% in fabricating and refinery facilities, respectively. Applying protection factors to TPM measurements significantly reduced estimated job mean TPM exposures and changed exposure categories in these facilities, with larger impact in smelting than fabricating facilities. Conclusions Respirator use varied by time, facility and job. Adjusting respirator use resulted in differential impact in smelting and fabricating facilities, which will need to be incorporated into ongoing epidemiologic studies accordingly.

Prioritizing Type of Industry through Health Risk Assessment of Occupational Exposure to Dimethylformamide in the Workplace.

The purpose of this study was to classify hazards at an industrial level and evaluate the exposure risks of workers exposed to dimethylformamide (DMF) used as a solvent in the workplace and to determine industries that need priority measures in managing DMF exposure. We calculated hazard quotients at an industrial level. The exposure data of DMF in the workplace were obtained from the work environment monitoring program provided by the Korea Occupational Safety and Health Agency. The evaluation was conducted on textile manufacturing, leather manufacturing, chemical manufacturing, pharmaceutical manufacturing, and rubber manufacturing industries, which have many unit work sites handling DMF. The highest central tendency exposure and reasonable maximum exposure were 2.13 and 18.66 mg/m³ for the rubber product manufacturing industry, respectively. A total of 63.8% of workplaces in the textile manufacturing sector had a hazard quotient higher than 1. The highest risk for exposure to DMF is in the rubber and plastic manufacturing industry, and the lowest risk was in the medical materials and pharmaceutical manufacturing sector. Based on this study, effective management of DMF exposure could be achieved by establishing priority management measures for the textile and rubber and plastic product industries.

PAH exposure-associated lung cancer: an updated meta-analysis.

Background: Occupational exposure to polycyclic aromatic hydrocarbons (PAHs) has been shown to be associated with lung cancer in various epidemiological studies in industries such as aluminium reduction/smelting, coal gasification, coke production, iron/steel foundries, coal/coke and related products and carbon/graphite electrodes production. Aims: To update data on the association between PAH exposure and morbidity and mortality due to lung cancer among workers in different occupations, including smoking data. Methods: A comprehensive literature search was conducted to retrieve relevant papers for meta-analysis. Cohort studies with standardized mortality ratios or standardized incidence ratios and calculated overall risk ratio with their corresponding 95% confidence intervals (CIs) were included in the analysis. Chi-square test for heterogeneity was used to evaluate the consistency of findings between the studies. Results: A significant risk of lung cancer was observed among the coal/coke and related product industry 1.55 (95% CI 1.01-2.37) and the iron/steel foundry industry 1.52 (95% CI 1.05-2.20). There was a wide variation in smoking habits and PAHs exposure among studies. Conclusions: Coal/coke industry and iron/steel industry workers showed a higher risk of lung cancer compared with other occupations exposed to PAHs. The confounding effects of smoking and individual exposure levels of PAH should be taken into account.

Urine cytology screening of French workers exposed to occupational urinary tract carcinogens: a prospective cohort study over a 20-year period.

OBJECTIVES: To demonstrate that urine cytology screening can provide relevant epidemiological data for earlier detection of urothelial cancer caused by occupational exposure. DESIGN: Prospective cohort study. SETTING: Industries using urothelial carcinogens in France. Urine samples were collected on site, after a work week and were analysed at the University Hospital of Clermont-Ferrand, France. PARTICIPANTS: Participants were workers exposed to urothelial carcinogens. Women and current smokers at time of study recruitment were exclusion criteria. OUTCOMES: Urine cells atypia were ranged into three classes: negative/normal, atypical/suspicious/dysplasia or positive/malignant. RESULTS: We included 2020 workers over a period of 20 years from 1993 to 2013: 606 worked in rubber manufacturing, 692 from metal processing, 245 in chemical industry and 477 in roadwork and building industry. Workers had a mean exposure of 15.2±10.4 years before their first urine cytology screening. There was a mean of 3.4±4.3 urine cytology screenings per worker between 1993 and 2013. 6478 cytology were normal, 462 suspicious and 13 malignant. Suspicious and malignant cytology occurred in 4.8% of workers exposed for 1-10 years, 6.2% for 11-20 years of exposure, 7.6% for 21-30 years and 8.6% for >30 years (p<0.001). Using exposure for 1-10 years as reference, the adjusted OR of receiving a suspicious or malignant diagnosis increased with duration of exposure: OR=1.50 (95% CI 1.10 to 2.05, p=0.01) for 21-30 years and OR=1.78 (95% CI 1.23 to 2.56, p=0.002) for >30 years of exposure. Using metal processing as reference, the risk of pathological urine cytology results increased for rubber manufacturing (OR=1.32, 95% CI 1.05 to 1.65, p=0.02), with a trend for roadwork and building industry (OR=1.39, 95% CI 0.98 to 1.97, p=0.07) and for chemical industry (OR=1.34, 95% CI 0.94 to 1.93, p=0.11). CONCLUSIONS: Urine cytology is a useful tool in occupational medicine. We promote new guidelines with an early screening of urothelial cancer by cytology, starting with beginning of exposure.

Total and Cause-Specific Mortality Risk Associated With Low-Level Exposure to Crystalline Silica: A 44-Year Cohort Study From China.

The association between low-level crystalline silica (silica) exposure and mortality risk is not well understood. We investigated a cohort of 44,807 Chinese workers who had worked in metal mines or pottery factories for at least 1 year from January 1, 1960, to December 31, 1974, and were followed through 2003. Low-level silica exposure was defined as having a lifetime highest annual mean silica exposure at or under a permissible exposure limit (PEL). We considered 3 widely used PELs, including 0.05 mg/m3, 0.10 mg/m3, and 0.35 mg/m3. Cumulative silica exposure was estimated by linking a job exposure matrix with each participant's work history. For the 0.10-mg/m3 exposure level, Cox proportional hazards models showed significantly increased risk of mortality from all diseases (for each 1-ln mg/m3-years increase in logged cumulative silica exposure, hazard ratio (HR) = 1.05, 95% confidence interval (CI): 1.03, 1.07), malignant neoplasms (HR = 1.06, 95% CI: 1.03, 1.09), lung cancer (HR = 1.08, 95% CI: 1.02, 1.14), ischemic heart disease (HR = 1.09, 95% CI: 1.02, 1.16), pulmonary heart disease (HR = 1.08, 95% CI: 1.00, 1.16), and respiratory disease (HR = 1.20, 95% CI: 1.14, 1.26). The 0.05-mg/m3 and 0.35-mg/m3 exposure levels yielded similar associations. Long-term exposure to low levels (PELs ≤0.05 mg/m3, ≤0.10 mg/m3, or ≤0.35 mg/m3) of silica is associated with increased total and certain cause-specific mortality risk. Control of ambient silica levels and use of personal protective equipment should be emphasized in practice.

Occupational health profile of workers employed in the manufacturing sector of India.

BACKGROUND: The occupational health scenario of workers engaged in the manufacturing sector in India deserves attention for their safety and increasing productivity. We reviewed the status of the manufacturing sector, identified hazards faced by workers, and assessed the existing legislations and healthcare delivery mechanisms. METHODS: From October 2014 to March 2015, we did a literature review by manual search of pre-identified journals, general electronic search, electronic search of dedicated websites/databases and personal communication with experts of occupational health. RESULTS: An estimated 115 million workers are engaged in the manufacturing sector, though the Labour Bureau takes into account only one-tenth of them who work in factories registered with the government. Most reports do not mention the human capital employed neither their quality of life, nor occupational health services available. The incidence of accidents were documented till 2011, and industry-wise break up of data is not available. Occupational hazards reported include hypertension, stress, liver disease, diabetes, tuberculosis, eye/ hearing problems, cancers, etc. We found no studies for manufacturing industries in glass, tobacco, computer and allied products, etc. The incidence of accidents is decreasing but the proportion of fatalities is increasing. Multiple legislations exist which cover occupational health, but most of these are old and have not been amended adequately to reflect the present situation. There is a shortage of manpower and occupational health statistics for dealing with surveillance, prevention and regulation in this sector. CONCLUSION: There is an urgent need of a modern occupational health legislation and an effective machinery to enforce it, preferably through intersectoral coordination between the Employees' State Insurance Corporation, factories and state governments. Occupational health should be integrated with the general health services.

A study update of mortality in workers at a phosphate fertilizer production facility.

OBJECTIVE: To evaluate the mortality experience among 3,199 workers employed 1951-1976 at a phosphate fertilizer production plant in central Florida with follow-up through 2011. METHODS: Cause-specific standardized mortality ratios (SMRs) for the full cohort were calculated with the U.S. population as referent. Lung cancer and leukemia risks were further analyzed using conditional logistic regression. RESULTS: The mortality due to all-causes (SMR = 1.07, 95% confidence interval [CI] 1.02-1.13, observed deaths [n] = 1,473), all-cancers (SMR = 1.16, 95%CI 1.06-1.28, n = 431), and a priori outcomes of interests including lung cancer (SMR = 1.32, 95%CI = 1.13-1.53, n = 168) and leukemia (SMR = 1.74, 95%CI = 1.11-2.62, n = 23) were statistically significantly elevated. Regression modeling on employment duration or estimated radiation scores did not show exposure-response relation with lung cancer or leukemia mortality. CONCLUSION: SMR results showed increased lung cancer and leukemia mortality in a full cohort of the phosphate fertilizer production facility. There was, however, no exposure-response relation observed among cases and matched controls.