BACKGROUND: Acute nonfatal occupational inhalation injuries are caused by exposures to airborne toxicants and contaminants in the workplace. A 1990s study found that US emergency department (ED)-based inhalation injury rates were higher than those seen in the United Kingdom and Canada. This study examines 4 years of hospital ED data to estimate current rates of occupational inhalation injuries. METHODS: Data from the National Electronic Injury Surveillance System Occupational Supplement were used to identify nonfatal occupational inhalation injuries treated in US hospital EDs from 2014 to 2017. A workplace inhalation injury was defined as any worker treated in an ED as a result of inhaling a harmful substance at work. RESULTS: From 2014 to 2017, there were an estimated 2.2 occupational inhalation injuries per 10,000 full-time equivalents (FTE) (95% confidence interval [CI]: 1.6-2.8) treated in EDs, a rate nearly four times that found in Bureau of Labor Statistics data. Although men incurred 60% (95% CI: 56%-64%) of the injuries, the overall injury rates for men and women were similar at 2.3 (95% CI: 1.7-2.9) and 2.1 (95% CI: 1.4-2.7) per 10,000 FTE, respectively. By age group, workers less than 25 years of age were at greater risk of injury at 4.1 injuries per 10,000 FTE (95% CI: 2.8-5.3). CONCLUSIONS: These results illustrate the burden of nonfatal occupational inhalation injuries, providing an understanding of how injuries are distributed based on demographics. While inhalation injury rates have declined over the last two decades, additional research is needed to determine whether interventions have reduced risk, or if the availability of alternate sources of medical treatment is a factor.

Silicosis is usually a disease of long latency affecting mostly older workers; therefore, silicosis deaths in young adults (aged 15-44 years) suggests acute or accelerated disease. To understand the circumstances surrounding silicosis deaths among young persons, CDC analyzed the underlying and contributing causes of death using multiple cause-of-death data (1999-2015) and industry and occupation information abstracted from death certificates (1999-2013). During 1999-2015, among 55 pneumoconiosis deaths of young adults with International Classification of Diseases, Tenth Revision (ICD-10) code J62 (pneumoconiosis due to dust containing silica), section sign 38 (69%) had code J62.8 (pneumoconiosis due to other dust containing silica), and 17 (31%) had code J62.0 (pneumoconiosis due to talc dust) listed on their death certificate. Decedents whose cause of death code was J62.8 most frequently worked in the manufacturing and construction industries and production occupations where silica exposure is known to occur. Among the 17 decedents who had death certificates listing code J62.0 as cause of death, 13 had certificates with an underlying or a contributing cause of death code listed that indicated multiple drug use or drug overdose. In addition, 13 of the 17 death certificates listing code J62.0 as cause of death had information on decedent's industry and occupation; among the 13 decedents, none worked in talc exposure-associated jobs, suggesting that their talc exposure was nonoccupational. Examining detailed information on causes of death (including external causes) and industry and occupation of decedents is essential for identifying silicosis deaths associated with occupational exposures and reducing misclassification of silicosis mortality.

CDC's National Institute for Occupational Safety and Health (NIOSH), state health departments, and other state entities maintain a state-based surveillance program of confirmed silicosis cases. Data on confirmed cases are collected and compiled by state entities and submitted to CDC. This report summarizes information for cases of silicosis that were reported to CDC for 2003-2011 by Michigan and New Jersey, the only states that continue to provide data voluntarily to NIOSH. The data for this report were final as of January 8, 2015. Data are presented in tabular form on the number and distribution of cases of silicosis by year (Table 1), duration of employment in occupations with potential exposure to dust containing respirable crystalline silica (Table 2), industry (Table 3), and occupation (Table 4). The number of cases by year is presented graphically (Figure). This report is a part of the Summary of Notifiable Noninfectious Conditions and Disease Outbreaks - United States, which encompasses various surveillance years but is being published in 2016 (1). The Summary of Notifiable Noninfectious Conditions and Disease Outbreaks appears in the same volume of MMWR as the annual Summary of Notifiable Infectious Diseases (2).

CDC's National Institute for Occupational Safety and Health (NIOSH), state health departments, and other state entities maintain a state-based surveillance program of confirmed silicosis cases. Data on confirmed cases are collected and compiled by state entities and submitted to CDC. This report summarizes information for cases of silicosis that were reported to CDC for 2003–2010. The data for this report were final as of December 31, 2010. Data are presented in tabular form on the prevalence of silicosis, the number of cases and the distribution of cases by year, industry, occupation, and the duration of occupational exposure to dust containing respirable crystalline silica (Tables 1–4). The number of cases by year is presented graphically (Figure). This report is a part of the first-ever Summary of Notifiable Noninfectious Conditions and Disease Outbreaks, which encompasses various surveillance years but is being published in 2015 (1). The Summary of Notifiable Noninfectious Conditions and Disease Outbreaks appears in the same volume of MMWR as the annual Summary of Notifiable Infectious Diseases (2). | Background | Silicosis, a form of pneumoconiosis, is a progressive occupational lung disease caused by the inhalation, deposition, and retention of respirable dust containing crystalline silica. There is no effective specific treatment, and patients with silicosis can be offered only supportive care. Silicosis is preventable by using non-silica substitution materials, effective dust control measures, and personal protective equipment.* Occupational exposure to respirable dust containing crystalline silica occurs in mining, quarrying, sandblasting, rock drilling, construction, pottery making, stone masonry, and tunneling operations (3). The Occupational Safety and Health Administration (OSHA) estimates that approximately 2.2 million workers are currently exposed† to respirable crystalline silica in industries where exposure might occur: 1.85 million workers in the construction industry and 320,000 workers in general industry and maritime workplaces (4,5). Typically a disease of long latency, silicosis usually is diagnosed through a chest radiograph after ≥10 years of exposure to respirable crystalline silica dust. Nodular silicosis can also develop within 5–10 years of exposure to higher concentrations of crystalline silica. A clinical continuum exists between the accelerated and the chronic forms of silicosis. Acute silicosis has a different pathophysiology than accelerated or chronic silicosis. It might develop within weeks of initial exposure and is associated with exposures to extremely high concentrations† of crystalline silica. Respiratory impairment is severe, and the disease is usually fatal within a year of diagnosis. In addition, occupational exposure to respirable crystalline silica puts workers at increased risk for other serious health conditions including chronic obstructive lung disease, kidney and connective tissue disease, tuberculosis and other mycobacterial-related diseases, and lung cancer (6). In 1997, the International Agency for Research on Cancer classified crystalline silica as carcinogenic to humans (7), and this classification was reconfirmed in 2012 (8). | During 1968–2010, the number of deaths in the United States for which silicosis was listed on the death certificate declined from 1,065 (age-adjusted death rate: 8.21 per million persons aged ≥15 years) in 1968 to 101 (rate: 0.39) in 2010 (9). Analysis of 1968–2005 data indicated that silicosis-attributable years of potential life lost before age 65 years decreased substantially during 1968–2005, but the decline slowed during the last 10 years of that period (10). However, no decline occurred in the number of hospitalizations for which silicosis was listed as one of the discharge diagnoses during 1993–2011.§ Cases of silicosis continue to occur despite the existence of legally enforceable exposure limits.† Silicosis in any of its clinical forms is consistently undercounted by the Survey of Occupational Injuries and Illnesses (SOII), an employer-based surveillance system maintained by the Bureau of Labor Statistics (11). Estimates indicate that 3,600–7,300 new cases of silicosis might be occurring each year (11). In 2008, the National Academy of Sciences recommended that surveillance efforts to prevent silicosis and other interstitial lung diseases be continued and expanded (12). | Cases of silicosis are sentinel events that indicate the need for intervention (13). Silicosis was first designated as a notifiable condition at the national level in 1999¶ and reconfirmed in 2009.** In 2010, silicosis was a reportable condition in 25 states.†† | NIOSH has supported efforts by states to conduct surveillance for silicosis under several cooperative agreements, including the Sentinel Event Notification system for Occupational Risks (SENSOR) and the State-Based Occupational Safety and Health Surveillance agreements. In 1987, states initiated active silicosis surveillance under SENSOR and began providing data voluntarily to NIOSH (14,15). Since 1992, data summaries have been published in a series of reports.§§ The number of states¶¶ that conduct silicosis surveillance varies by year based on funding support by NIOSH. Currently, Michigan and New Jersey continue to maintain their sentinel case-based silicosis surveillance systems and intervention programs. These two states are the only states that continue to provide data voluntarily to NIOSH. | This report summarizes data for silicosis cases that met the surveillance case definition for a confirmed silicosis case for the period 2003–2010 as reported by Michigan and New Jersey. Data from state programs are updated annually and are available through the CDC's Work-Related Lung Disease Surveillance System (eWoRLD).***

Silicosis is a potentially fatal but preventable occupational lung disease caused by inhaling respirable crystalline silica (silica). Chronic silicosis, the most common form, occurs after exposure to relatively low silica concentrations for >10 years. Accelerated silicosis occurs after 5-10 years of exposure to higher silica levels, and acute silicosis can occur after only weeks or months of exposure to extremely high silica concentrations. New national mortality data for silicosis have become available since a previous report on silicosis surveillance was published earlier this year. CDC reviewed multiple cause-of-death mortality files from the National Center for Health Statistics to analyze deaths from silicosis (International Classification of Diseases, 10th Revision diagnosis code J62: a pneumoconiosis due to dust containing silica) reported during 1999-2013. Each record lists one underlying cause of death (the disease or injury that initiated the chain of events that led directly and inevitably to death), and up to 20 contributing causes of death (other significant conditions contributing to death but not resulting in underlying cause). Available death certificates from 35 states were reviewed for the period 2004-2006 to identify occupations associated with silicosis among decedents aged 15-44 years. Results indicate that despite substantial progress in eliminating silicosis, silicosis deaths continue to occur. Of particular concern are silicosis deaths in young adults (aged 15-44 years). These young deaths likely reflect higher exposures than those causing chronic silicosis mortality in older persons, some of sufficient magnitude to cause severe disease and death after relatively short periods of exposure. A total of 12 such deaths occurred during 2011-2013, with nine that had silicosis listed as the underlying cause of death.

The objective of this study was to estimate the prevalence of current asthma and the proportion of current asthma that is related to work on the farm among primary farm operators. The 2011 Farm and Ranch Safety Survey data were used to produce estimates and prevalence odds ratios. An estimated 5.1% of farm operators had asthma. Of these, 15.4% had farm work-related asthma. Among operators with farm work-related asthma, 54.8% (95% confidence interval [CI]: 41.8%-68.2%) had an asthma attack in the prior 12 months and 33.3% (95% CI: 21.2%-45.4%) had an asthma attack that occurred while doing farm work. Of those who had an asthma attack that occurred while doing farm work, 65.0% associated their asthma attack with plant/tree materials. This study provides updated information on asthma and the proportion of current asthma that is related to work on the farm and identifies certain groups of farm operators that might benefit from workplace asthma prevention intervention.

Because our original publication (1) generated considerable interest over the past two years, we now provide additional data from our nested case-control study that are valuable in evaluating the relation between diesel exhaust exposure and lung cancer. Here we include results based on alternative exposure metrics (Table 1) and alternative approaches for adjusting for cigarette smoking as a confounder (Table 2), for comparison with results that appeared in Table 3 of Silverman et al. (1).

The objective of this study was to estimate the national prevalence of respirator use among primary farm operators in the United States. The authors analyzed the 2006 Farm and Ranch Safety Survey data collected for 12,278 actively farming primary farm operators. Weighted prevalence and adjusted prevalence ratios (PRs) of respirator use were calculated by farm operator characteristics, farm characteristics, and selected exposures/hazards. Of the estimated 2.1 million farm operators, 37.2% used a respirator on their farm. Respirator use prevalence was significantly higher among operators aged 16-34 years than those aged ≥65 years (46.9% vs. 30.0%; PR = 1.6); male than female operators (39.0% vs. 24.4%; PR = 1.6); operators managing crop farms than operators managing livestock farms (40.9% vs. 33.7%; PR = 1.2); and operators managing farms with value of sales ≥$100,000 than operators managing farms with value of sales ≤$9999 (57.4% vs. 31.4%; PR = 1.8). Of the operators who used a respirator, 69.9% used while working in a dusty environment, 22.6% used while applying/handling pesticides, and 30.4% used while doing other farm-related activities. These results show that an estimated one third of operators used respirators in 2006, and respirator use is most frequent among operators working in a dusty environment. Additional research identifying specific exposures for which respirators or dust masks are used, barriers to respirator or dust mask use, motivators for wearing respirators, and opportunities to increase the use of respiratory protection among farm operators, particularly on smaller farms, is needed.

BACKGROUND: Current information points to an association between diesel exhaust exposure and lung cancer and other mortality outcomes, but uncertainties remain. METHODS: We undertook a cohort mortality study of 12,315 workers exposed to diesel exhaust at eight US non-metal mining facilities. Historical measurements and surrogate exposure data, along with study industrial hygiene measurements, were used to derive retrospective quantitative estimates of respirable elemental carbon (REC) exposure for each worker. Standardized mortality ratios and internally adjusted Cox proportional hazard models were used to evaluate REC exposure-associated risk. Analyses were both unlagged and lagged to exclude recent exposure such as that occurring in the 15 years directly before the date of death. RESULTS: Standardized mortality ratios for lung cancer (1.26, 95% confidence interval [CI] = 1.09 to 1.44), esophageal cancer (1.83, 95% CI = 1.16 to 2.75), and pneumoconiosis (12.20, 95% CI = 6.82 to 20.12) were elevated in the complete cohort compared with state-based mortality rates, but all-cause, bladder cancer, heart disease, and chronic obstructive pulmonary disease mortality were not. Differences in risk by worker location (ever-underground vs surface only) initially obscured a positive diesel exhaust exposure-response relationship with lung cancer in the complete cohort, although it became apparent after adjustment for worker location. The hazard ratios (HRs) for lung cancer mortality increased with increasing 15-year lagged cumulative REC exposure for ever-underground workers with 5 or more years of tenure to a maximum in the 640 to less than 1280 mcg/m(3)-y category compared with the reference category (0 to <20 mcg/m(3)-y; 30 deaths compared with eight deaths of the total of 93; HR = 5.01, 95% CI = 1.97 to 12.76) but declined at higher exposures. Average REC intensity hazard ratios rose to a plateau around 32 mcg/m(3). Elevated hazard ratios and evidence of exposure-response were also seen for surface workers. The association between diesel exhaust exposure and lung cancer risk remained after inclusion of other work-related potentially confounding exposures in the models and were robust to alternative approaches to exposure derivation. CONCLUSIONS: The study findings provide further evidence that exposure to diesel exhaust increases risk of mortality from lung cancer and have important public health implications.

BACKGROUND: Most studies of the association between diesel exhaust exposure and lung cancer suggest a modest, but consistent, increased risk. However, to our knowledge, no study to date has had quantitative data on historical diesel exposure coupled with adequate sample size to evaluate the exposure-response relationship between diesel exhaust and lung cancer. Our purpose was to evaluate the relationship between quantitative estimates of exposure to diesel exhaust and lung cancer mortality after adjustment for smoking and other potential confounders. METHODS: We conducted a nested case-control study in a cohort of 12,315 workers in eight non-metal mining facilities, which included 198 lung cancer deaths and 562 incidence density-sampled control subjects. For each case subject, we selected up to four control subjects, individually matched on mining facility, sex, race/ethnicity, and birth year (within 5 years), from all workers who were alive before the day the case subject died. We estimated diesel exhaust exposure, represented by respirable elemental carbon (REC), by job and year, for each subject, based on an extensive retrospective exposure assessment at each mining facility. We conducted both categorical and continuous regression analyses adjusted for cigarette smoking and other potential confounding variables (eg, history of employment in high-risk occupations for lung cancer and a history of respiratory disease) to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Analyses were both unlagged and lagged to exclude recent exposure such as that occurring in the 15 years directly before the date of death (case subjects)/reference date (control subjects). All statistical tests were two-sided. RESULTS: We observed statistically significant increasing trends in lung cancer risk with increasing cumulative REC and average REC intensity. Cumulative REC, lagged 15 years, yielded a statistically significant positive gradient in lung cancer risk overall (P(trend) = .001); among heavily exposed workers (ie, above the median of the top quartile [REC ≥ 1005 mcg/m(3)-y]), risk was approximately three times greater (OR = 3.20, 95% CI = 1.33 to 7.69) than that among workers in the lowest quartile of exposure. Among never smokers, odd ratios were 1.0, 1.47 (95% CI = 0.29 to 7.50), and 7.30 (95% CI = 1.46 to 36.57) for workers with 15-year lagged cumulative REC tertiles of less than 8, 8 to less than 304, and 304 mcg/m(3)-y or more, respectively. We also observed an interaction between smoking and 15-year lagged cumulative REC (P(interaction) = .086) such that the effect of each of these exposures was attenuated in the presence of high levels of the other. CONCLUSION: Our findings provide further evidence that diesel exhaust exposure may cause lung cancer in humans and may represent a potential public health burden.

Children with asthma can experience chronic morbidity that may interfere with education and career progression. The authors investigated retrospectively whether a history of childhood asthma is associated with educational level and longest-held occupation, by gender. Cross-sectional analysis included a nationally representative sample of 10,452 adults aged ≥20 years who participated in the US National Health and Nutrition Examination Survey (2001-2004). Logistic regression was used to assess associations between a childhood-asthma history and educational level, employment, and longest-held occupation. An estimated 6.9% of men and 5.8% of women had a childhood-asthma history. Persons with a childhood-asthma history tended to have a higher educational level than those with no asthma history. Among those who ever worked, and after adjustment for age and race/ethnicity, men with a childhood-asthma history were more likely to work in health-diagnosing occupations, other professional occupations, and as cooks; women with a childhood-asthma history were more likely to work in management-related, entertainment-related, and health service occupations. Compared with those with no asthma history, persons with a childhood-asthma history tended to achieve a higher educational level and, if they worked, were more likely to work in particular occupations.

BACKGROUND AND OBJECTIVES: The occupational history of every adult patient with asthma provides information critical to the proper diagnosis and effective prevention of work-related asthma. This study determined the proportion of farm operators that reported an asthma attack while doing farm work that required the use of an inhaler or other medical treatment but who had not been told by a doctor, nurse, or other health professional that their asthma was related to work on the farm. METHODS: Asthma and asthma attack prevalences were estimated using data on a nationally representative sample of 12,278 active farm operators who participated in the 2006 Farm and Ranch Safety Survey. RESULTS: An estimated 4.9% of operators reported current asthma. Of these, an estimated 24.8% had been told that their asthma was related to work on the farm. Of those not so informed, 21.6% reported an asthma attack at work in the 12 months prior to the interview. CONCLUSIONS: A large proportion of farm operators who had not been told that their asthma was related to work on the farm experienced an asthma attack that occurred while doing farm work. These results suggest the need for improving clinicians' occupational health practices and clinician-patient communication.