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The objective of this study was to estimate the risk of SARS-CoV-2 transmission among students and teachers in New York City public schools, the largest school system in the US. Classroom measurements conducted from December 2017 to September 2018 were used to estimate risk of SARS-CoV-2 transmission using a modified Wells-Riley equation under a steady-state conditions and varying exposure scenarios (infectious student versus teacher, susceptible student versus teacher, with and without masks). We then used multivariable linear regression with GEE to identify school and classroom factors that impact transmission risk. Overall, 101 classrooms in 19 schools were assessed, 86 during the heating season, 69 during cooling season, and 54 during both. The mean probability of transmission was generally low but varied by scenario (range: 0.0015-0.81). Transmission rates were higher during the heating season (beta=0.108, p=0.010), in schools in higher income neighborhoods (>80K versus 20K-40K beta=0.196, p<0.001) and newer buildings (<50 years beta=0.237, p=<0.001; 50-99 years beta=0.230, p=0.013 versus 100+ years) and lower in schools with mechanical ventilation (beta=0.141, p=0.057). Surprisingly, schools located in older buildings and lower-income neighborhoods had lower transmission probabilities, likely due to the greater outdoor airflow associated with an older, non-renovated buildings that allow air to leak in (i.e. drafty buildings). Despite the generally low risk of school-based transmission found in this study, with SARS-CoV-2 prevalence rising in New York City this risk will increase and additional mitigation steps should be implemented in schools now., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background: Hotel employees have higher rates of occupational injury and sustain more severe injuries than most other service workers., Method: OSHA log incidents from five unionized hotel companies for a three-year period were analyzed to estimate injury rates by job, company, and demographic characteristics. Room cleaning work, known to be physically hazardous, was of particular concern., Results: A total of 2,865 injuries were reported during 55,327 worker-years of observation. The overall injury rate was 5.2 injuries per 100 worker-years. The rate was highest for housekeepers (7.9), Hispanic housekeepers (10.6), and about double in three companies versus two others. Acute trauma rates were highest in kitchen workers (4.0/100) and housekeepers (3.9/100); housekeepers also had the highest rate of musculoskeletal disorders (3.2/100). Age, being female or Hispanic, job title, and company were all independently associated with injury risk., Conclusion: Sex- and ethnicity-based disparities in injury rates were only partially due to the type of job held and the company in which the work was performed., (Copyright 2009 Wiley-Liss, Inc.)

The 1998 National Institute for Occupational Safety and Health (NIOSH) criteria document for metalworking fluids (MWF) is the most recent authoritative review of mortality studies of workers with these exposures. NIOSH concluded that substantial evidence exists for increased risk of cancer at several sites (larynx, rectum, pancreas, skin, scrotum, and bladder) among workers exposed to MWF before the mid-1970s, and that evidence is equivocal for cancer at several other sites, including stomach, esophagus, lung, prostate, brain, colon, and hematopoietic system. The UAW believes that systematic analysis of that body of data makes a much stronger case for stomach cancer related to MWF exposure. Since the Criteria document, the mortality experience of three of the cohorts reviewed has been either updated or reanalyzed. These updates strengthen the evidence for increased mortality from stomach and liver cancer, and non-malignant respiratory disease associated with exposure to water-based metalworking fluids. Additional toxicological data providing clear evidence for carcinogenicity of diethanolamine, a widely used ingredient, also increases the biological plausibility of these findings. Despite changes in composition of MWFs with time, and reduced exposure levels, these data contradict the notion that cancer risks have been eliminated.

Mortality at two engine plants was analyzed using proportional mortality and logistic regression models of mortality odds ratios to expand previous observations of increased cancers of the stomach, pancreas, and bladder, and cirrhosis of the liver among workers exposed to machining fluids. Causes of death and work histories were available for 1,870 decendents. There was a significant excess of deaths coded as diabetes for white men in both plants (PMR = 25/16.7 = 1.5, 95% CI = 1.02, 2.20), and a deficit of respiratory diseases. Black men had fewer than expected diabetes deaths and more emphysema deaths. Elevated PMRs for cancers of the stomach, pancreas, prostate, bladder, and kidney were not statistically significant in plantwide populations. However, stomach cancer mortality increased with duration in camshaft and crankshaft production at Plant 1 (OR = 5.1, 95% CI = 1.6, 17; at mean duration of exposed cases), and among tool room workers (OR = 6.3, 95% CI = 1.3, 31), but these results were based on five cases. Nitrosamines were probably present in camshaft and crankshaft grinding at Plant 1. Pancreas cancer risk increased among workers at both plants ever employed in inspection (OR = 2.5, 16), in machining with straight oil (OR = 3.6, 95% CI = 1.04, 12), or in skilled trades (OR = 2.9, 95% CI = 1.1, 7.5). Lung cancer increased in cylinder head machining (OR = 3.9, 95% CI = 1.4, 11), millwright work (OR = 3.8, 95% CI = 1.6, 9.0), and in Plant 2 generally (OR = 1.45, 95% CI = 0.97, 2.2). Potential lung carcinogens included heat treatment emissions, chlorinated oils, and coal tar fumes (millwrights). Bladder cancer increased with duration among workers grinding in straight oil MF (OR = 3.0, 95% CI = 1.15, 7.8) and in machining/heat-treat operations (OR = 2.9, 95% CI = 1.14, 7.2).

Sickness and accident-insurance (sick leave) claims at an automotive stamping and assembly complex were analyzed using Poisson regression over a 4-year period to identify occupational health problems. The incidence of lower-respiratory disability (excluding asthma) was higher in painting operations (rate ratio [RR] = 2.9, 95% confidence interval [CI] = 1.2 to 6.8), and final assembly and processing areas (RR = 2.7, 95% CI = 1.0 to 7.4) at the assembly plant, and in metal assembly (welding) areas (RR = 2.8, 95% CI = 1.4 to 5.7) at the stamping plant. Disability rates for upper-extremity musculoskeletal disorders were statistically significantly higher (RR = 3.1 to 3.8) in major assembly plant production areas, as were back disability rates (RR = 1.5). During the first 6 months of new work assignments in painting or final assembly, respiratory problem rates were four times higher than in other areas. Upper-extremity musculoskeletal rate ratios ranged from 4.4 to 5.7 for new assignments in body, hard trim, and chassis areas. Higher rates in new assignments appeared to result from assignment changes precipitated by developing health problems, or from routine assignments to new tasks, some of which conferred high risk and were tolerated for less than 6 months. Musculoskeletal disability was consistent with known ergonomic hazards and paralleled that reported on the Occupational Safety and Health Administration log. Work-related musculoskeletal and other problems can be readily identified from disability insurance claims without dependence on plant medical visits or workers' compensation records. Disability insurance appears to absorb considerable work-related medical and absence costs.

Mortality among workers with 2 or more years employment at an automotive stamping and assembly complex was analyzed using standardized mortality ratio (SMR), proportional mortality ratio (PMR), and mortality odds ratio (MOR) methods. The stamping plant all-cause SMR was considerably less than expected (for white men, SMR = 0.65, 95% confidence interval [CI] = 0.54, 0.79; for black men, SMR = 0.73, 95% CI = 0.45, 1.13), indicating a strong "healthy worker effect." However, six stomach cancer deaths produced an SMR of 4.4 (95% CI = 1.62, 9.6) and a PMR of 6.8 (95% CI = 2.5, 15). Based on small numbers of cases, stomach cancer risk increased with duration in stamping and tool and die departments where exposures included drawing compound and other metalworking fluids. Stamping plant lung cancer mortality was elevated among production welders (MOR = 2.7, 95% CI = 1.2, 6.3), and increased with duration. Welding was performed on sheet metal sometimes coated with drawing compound, primer, or epoxy resin adhesive. As was observed for the stamping plant, the all-cause SMR for the two assembly plants was unusually low (for white men, SMR = 0.64, 95% CI = 0.56, 0.73; for black men, SMR = 0.57, 95% CI = 0.43, 0.75). The lung cancer SMR was not elevated but the MOR was (MOR = 1.58, 95% CI = 1.1, 2.4) and increased with assembly plant duration (MOR = 1.78, 95% CI = 1.02, 3.1, at mean duration of cases). In the assembly plants, paint oven stack emissions had been reintroduced into the plant by the ventilation system.

Medical insurance claims, linked with work histories for a large automotive manufacturer over a 3-year period, identified large numbers of cases of potentially work-related diseases, including 30,600 episodes of probable cumulative trauma disorders (CTD). CTD incidence rates were calculated within five plants, and high-risk areas identified, however, unknown differences in medical insurance coverage by exposure group limited interpretation. Case-control analyses, with controls also identified by insurance claims, addressed coverage and produced age-adjusted and sex-adjusted estimates of risks. All five plants had departments with statistically significant, elevated risks for one or more of the diagnoses carpal tunnel syndrome, CTD of other upper extremities, rotator cuff syndrome, CTD of the neck and of the lower back. Medical insurance claim data linked with work history provide the basis for practical and comprehensive surveillance for CTD and potentially a variety of other occupational diseases.

Standardized proportional mortality ratios and mortality odds ratios were calculated for 583 deaths between 1950 and 1986 among employees who had worked for at least 10 years at a facility manufacturing missile and aircraft guidance systems. There was a statistically significant excess of brain cancer proportional mortality (PMR = 16/3.8 = 4.2, p = .0001). Among hourly employees, 12 brain cancer deaths occurred for 2.7 expected (PMR = 4.4, p = .00005). The PMR for brain cancer increased from 1.8 (p = .45) among hourly workers with less than 20 years to 8.7 (p = .000003) in those with more than 20 years employment. Work in "clean rooms," where gyroscopes were assembled, was associated with the brain cancer excess but did not fully account for it. Among 105 deceased hourly women, all three brain cancer deaths occurred among gyro assemblers working in clean rooms, and the risk increased with duration in clean rooms. Although the proportion of brain cancer deaths among hourly men with clean-room experience was similar to that for women, only three of the seven male brain cancer deaths occurred in this group. The suspect agents include gyro fluids and chlorofluorocarbon solvents.

Mortality analyses were carried out for 278 male hourly workers who were employed for at least 10 years at a gray iron foundry and who died between January 1, 1970 and December 31, 1981. Statistically significant excess proportional mortality due to non-malignant respiratory disease (SPMR = 177), lung cancer (SPMR = 148), and leukemia (SPMR = 284) was found among the 221 white males. Among nonwhite males there was a significant excess in proportional mortality due to circulatory diseases (SPMR = 143). White males in the Finishing classification experienced a significant excess of proportional mortality due to nonmalignant respiratory disease (SPMR = 279) and lung cancer (SPMR = 179). White males in the Core Room classification experienced an excess of proportional mortality due to nonmalignant respiratory disease (SPMR = 321). Case-control studies demonstrated a significant association between nonmalignant respiratory disease and the Finishing classification after controlling for the effects of age, prior occupations in coal mining or foundries, and smoking. A positive but nonsignificant association between lung cancer and Finishing was also found after controlling for age, prior work history, and smoking in case control studies.

A proportional mortality and case-referent analysis of 238 deaths among hourly employees in an automobile hardware manufacturing plant was conducted. The major operations of the plant were zinc die casting and electroplating. Chemical exposure included die-casting emissions and mists from chrome and nickel plating. The chief proportional mortality finding was a significant excess of lung cancer among both white men and women. A case-referent analysis indicated a possible association between lung cancer and work in certain departments. The findings support the hypothesis of a work-related carcinogenic risk. Follow-up recommendations have been made.

Hazardous chemical exposures may be a more important public health problem in chemical-using industries, such as the metalworking and transportation equipment industries, than in chemical manufacturing plants. Recent studies have identified excess mortality from cancer among groups of workers in model and patternmaking, plating and die-cast, foundry, machining, electronics operations and vehicle assembly plants. The chemical agents or levels of exposure associated with these findings have not previously been thought to pose a cancer risk. Therefore, estimates of the fraction of cancers associated with workplace exposure may understate the importance of exposure in this setting.

Epidemiologic studies have reported associations between gastrointestinal cancer mortality and exposure to cutting fluids and abrasives in metal machining and precision grinding operations. Two previous studies found excess stomach cancer among workers exposed to water-based cutting fluids in bearing plants. This study reports similar findings in a third and larger population. Cause of death and work histories were determined for 1,766 bearing plant workers who died between Jan 1, 1950 and June 30, 1982. Mortality odds ratios (SMOR) and proportional mortality ratios (PMR) revealed significant excesses of gastrointestinal malignancies. The proportional mortality excess for stomach cancer among white men was greatest among those with more than 10 years' exposure in the major grinding group (PMR = 13/3.8 = 3.39; P less than .001). The SMOR by logistic regression for stomach cancer among white men was 2.3 (P = .02) for 25 years' grinding experience. For cancer of the pancreas among white men, there were significant associations with both machining and grinding jobs in straight oil (SMOR = 9.9 and 3.2, respectively, for 25 years duration). These findings could not be explained by confounding due to the ethnic background of the decedents. This study confirms previous evidence that grinding operations using water-based cutting fluids increase the risk for stomach cancer and provides moderate evidence that exposures to straight oil-cutting fluids increase the risk for cancer of the pancreas. There were indications, meriting further investigation, that non-malignant liver disease is associated with cutting fluid exposures and that lung cancer is associated with oil smoke from operations such as forging or heat treating.

Recent studies identify digestive cancer excesses among workers exposed to cutting fluids, abrasive dusts, and oil smoke. Standardized proportional mortality and mortality odds ratio studies were carried out for a ball bearing plant. Cause of death and work histories were obtained for 702 of 768 hourly employees with ten or more years' service who died between 1969 and 1982. Union and company records were used to define exposure measures. The major findings were significant excesses in proportional mortality ratios (PMR) from stomach cancer (PMR = 2.0) and rectal cancer (PMR = 3.1) among white men. After control for age at death, there was a significant association between stomach cancer and precision grinding exposures, consisting primarily of direct contact with water-based cutting fluids (usually emulsified oils) and their aerosols. Some straight oils and synthetic cutting fluids were used as well. The pattern of stomach cancer is consistent with previous findings and suggests an association with the soluble oil cutting fluids.