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BackgroundAn estimated 110 million workers are exposed to welding fumes worldwide. Welding fumes are classified by the International Agency for Research on Cancer as carcinogenic to humans(group 1), based on sufficient evidenceof lung cancer from epidemiological studies.ObjectiveTo conduct a meta-analysis of case-control and cohort studies on welding or exposure to welding fumes and risk of lung cancer, accounting for confounding by exposure to asbestos and tobacco smoking.MethodsThe literature was searched comprehensively in PubMed, reference lists of relevant publications and additional databases. Overlapping populations were removed. Meta-relative risks (mRRs) were calculated using random effects models. Publication bias was assessed using funnel plot, Eggers’s test and Begg’s test.ResultsForty-five studies met the inclusion criteria (20 case-control, 25 cohort/nested case-control), which reduced to 37 when overlapping study populations were removed. For ‘ever’ compared with ‘never’ being a welder or exposed to welding fumes, mRRs and 95% CIs were 1.29 (1.20 to 1.39; I2=26.4%; 22 studies) for cohort studies, 1.87 (1.53 to 2.29; I2=44.1%; 15 studies) for case-control studies and 1.17 (1.04 to 1.38; I2=41.2%) for 8 case-control studies that adjusted for smoking and asbestos exposure. The mRRs were 1.32 (95% CI 1.20 to 1.45; I2=6.3%; 15 studies) among ‘shipyard welders’, 1.44 (95% CI 1.07 to 1.95; I2=35.8%; 3 studies) for ‘mild steel welders’ and 1.38 (95% CI 0.89 to 2.13; I2=68.1%; 5 studies) among ‘stainless steel welders’. Increased risks persisted regardless of time period, geographic location, study design, occupational setting, exposure assessment method and histological subtype.ConclusionsThese results support the conclusion that exposure to welding fumes increases the risk of lung cancer, regardless of the type of steel welded, the welding method (arc vs gas welding) and independent of exposure to asbestos or tobacco smoking.

ObjectiveTo investigate the carcinogenicity of styrene by reanalysing data from a previous international cohort study of workers in the reinforced plastics industry.MethodsMortality from cancers of prior interest was analysed with more detailed consideration of exposure–response relations and an updated classification of leukaemias and lymphomas in data from a previous international cohort study of 37 021 reinforced plastics workers exposed to airborne styrene.ResultsIncreased mortality from non-Hodgkin’s lymphoma (NHL) was associated with the mean level of exposure to styrene in air (relative risk (RR) 2.31, 95% CI 1.29 to 4.12 per 100 ppm), but not with cumulative styrene exposure. Similar associations with mean exposure were observed for the oesophagus (RR 2.44, 95% CI 1.11 to 5.36 per 100 ppm) and pancreas (RR 1.89, 95% CI 1.17 to 3.09). Oesophageal cancer mortality was also associated with cumulative styrene exposure lagged 20 years (RR 1.16, 95% CI 1.03 to 1.31). No other cancer, including lung cancer, was associated with any indicator of styrene exposure.ConclusionThis reanalysis does not substantially change the conclusions of the original study with respect to NHL or lung cancer but new evidence concerning cancers of the oesophagus and pancreas merits further investigation.

The recognition of occupational carcinogens is important for primary prevention, compensation and surveillance of exposed workers, as well as identifying causes of cancer in the general population. This study updates previously published lists of known occupational carcinogens while providing additional information on cancer type, exposure scenarios and routes, and discussing trends in the identification of carcinogens over time. Data were extracted from International Agency for Research on Cancer (IARC) Monographs covering the years 1971–2017, using specific criteria to ensure occupational relevance and provide high confidence in the causality of observed exposure-disease associations. Selected agents were substances, mixtures or types of radiation classified in IARC Group 1 with ‘sufficient evidence of carcinogenicity’ in humans from studies of exposed workers and evidence of occupational exposure documented in the pertinent monograph. The number of known occupational carcinogens has increased over time: 47 agents were identified as known occupational carcinogens in 2017 compared with 28 in 2004. These estimates are conservative and likely underestimate the number of carcinogenic agents present in workplaces. Exposure to these agents causes a wide range of cancers; cancers of the lung and other respiratory sites, followed by skin, account for the largest proportion. The dominant routes of exposure are inhalation and dermal contact. Important progress has been made in identifying occupational carcinogens; nevertheless, there is an ongoing need for research on the causes of work-related cancer. Most workplace exposures have not been evaluated for their carcinogenic potential due to inadequate epidemiologic evidence and a paucity of quantitative exposure data.

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OBJECTIVE To identify potential risk factors associated with a sudden increase in gastroschisis cases in northern Nevada. DESIGN Case-control study. SETTING Medical centers and a pregnancy care center in Reno, Nevada. PARTICIPANTS Participants (n = 14) were women who gave birth to infants with gastroschisis at either of the 2 medical centers in Reno, Nevada, from April 5, 2007, through April 4, 2008. Controls (n = 57) were selected from the same pregnancy center providing perinatal care to the cases and were matched 4:1 to the case mothers by maternal date of birth within 1 year. MAIN EXPOSURES Environmental exposures and illnesses during pregnancy. OUTCOME MEASURES Association of gastroschisis with illnesses, medications, or environmental exposures. RESULTS Gastroschisis was associated with the use of methamphetamine (odds ratio [OR], 7.15; 95% confidence interval [CI], 1.35-37.99) or any vasoconstrictive recreational drug (methamphetamine, amphetamine, cocaine, ecstasy) (OR, 4.46; 95% CI, 1.21-16.44) before pregnancy. When we limited self-reported illnesses to those occurring during the first trimester of pregnancy, chest colds (OR, 16.77; 95% CI, 1.88-150.27) and sore throats (OR, 12.72; 95% CI, 1.32-122.52) were associated with gastroschisis. CONCLUSIONS These findings add strength to the hypothesis that use of methamphetamine and related drugs is a risk factor for gastroschisis and raise questions about the risks associated with infections.Arch Pediatr Adolesc Med. 2009;163(11):1000-1006--

People with less education in Europe, Asia, and the United States are at higher risk of mortality associated with daily and longer-term air pollution exposure. We examined whether educational level modified associations between mortality and ambient particulate pollution (PM10) in Latin America, using several timescales.

Previous studies suggest that elevated exposure to drinking water disinfection by-products (DBPs)—in particular, total trihalomethanes (TTHMs)—may lead to fetal growth restriction. We examined the effects of exposure to TTHMs, haloacetic acids, and total organic halide on the probability of delivering a small-for-gestational-age (SGA) infant and on birth weight at term.

Recent studies suggest elevated exposure to drinking water disinfection by-products (DBPs) may be associated with decreased risk of preterm birth. We examined this association for exposure to total trihalomethanes (TTHMs), 5 haloacetic acids (HAA5), and total organic halides.

This study compared the occurrence of child maltreatment in military and nonmilitary populations. Data came from the National Child Abuse and Neglect Data System. All cases of child maltreatment substantiated from January 1, 2000 through December 31, 2002, in the state of Texas were analyzed. The rate of occurrence of substantiated maltreatment was lower for children in military families compared with children in nonmilitary families (5.05 vs. 7.89 per 1000 person-years). A greater proportion of caretakers of children in nonmilitary families compared with military families reportedly had financial problems (18.7% vs. 5.2%) and received public assistance (28.2% vs. 8.9%). The rate of occurrence of substantiated child maltreatment appears to be lower in military than nonmilitary families. The proportion of families with financial problems and public assistance is lower in military than nonmilitary families, suggesting that these factors may increase stress in families and the risk of maltreatment.

State vital records are often used to select population‐based controls in record‐linkage studies of birth defects. However, locating and contacting individuals based on these data sources to collect additional data can be a challenge.A large case‐control study of air quality and birth defects was conducted in 7 Texas counties in which cases were selected from the Texas Birth Defects Registry and controls from state vital records. In 2004, data from these sources were used to trace mothers of cases and controls who delivered babies in the year 2000 (n = 2477) for participation in a computer‐assisted telephone interview. A number of factors that predicted whether an individual would be located and interviewed were identified.Between March and August 2004, 38% of the mothers were located, and 38% of the located mothers were interviewed. Case mothers were more likely than control mothers to be located (44 vs. 30%) and, if located, to be interviewed (43 vs. 31%). We compared the characteristics of mothers who were not located (case n = 760; control n = 777), mothers who were located but not interviewed (case n = 344; control n = 236), and mothers who were interviewed (case n = 256; control n = 104). Among both cases and controls, older mothers (≥30 years) were more likely than younger mothers to be located, and non‐Hispanic black mothers were least likely to be located and interviewed.Despite the utility of vital records as a source of population‐based controls in record‐linkage analyses, the poor response rate discourages the use of these data sources to contact individuals for a follow‐up study 4 years after delivery. Birth Defects Research (Part A), 2005. © 2005 Wiley‐Liss, Inc.

We evaluated whether associations between PM10and daily mortality in Mexico City differ by the PM10measurement device or by regional differences in particle composition. Additionally, we reanalyzed previously collected data in light of recent insights about flaws in commonly used time series analysis techniques. We examined daily associations between mortality and four indicators of ambient PM10using Poisson regression, controlling for temperature and time trends with cubic natural splines. Associations were calculated for five subregions corresponding to five monitoring sites and pooled for the entire metropolitan area. PM10was measured with three methods: Tapered Element Oscillating Microbalance (TEOM), Sierra–Anderson High Volume (Hi-Vol) and Harvard Impactor (HI), the latter only at one site. In addition, predicted values of daily PM10were developed using the Hi-Vol measurements, which were taken every sixth day, and weather, visibility and other pollutant data. We assigned deaths to the exposure from the monitor nearest to their residence. We also re-evaluated the HI PM2.5and mortality association in southwest Mexico City, which was estimated previously using nonparametric statistical models. Slight decreases in effect estimates were observed (a 1.45% increase (95% CI: 0.09%, 2.83%) in total mortality per 10 μg/m3increment of PM2.5at lag 0) compared to a 1.68% change (95% CI: 0.45%, 2.93%) using the previously employed nonparametric approach. Using data pooled over all the regions, PM10measured by the TEOM and the predicted PM10values showed little association with mortality at any of the lags examined. The pooled estimates for Hi-Vol PM10(using one sixth of the data) were positive across all lags examined and significant for lags 3 and 5. No consistent patterns of differing associations were seen across regions that would correspond with particle toxicity or composition. Particulate air pollution, measured with gravimetric methods, is associated with daily mortality and presents a risk to health in Mexico City. The reanalysis suggests that previous research is robust to statistical method and likely to yield the same overall conclusions about the short-term effects of airborne particles on mortality.Journal of Exposure Analysis and Environmental Epidemiology (2004) 14, 429–439. doi:10.1038/sj.jea.7500341 Published online 17 March 2004

This study examines the hypothesis that acid mist or mixtures of acid mists and acid gases are associated with ulcerative lesions of the oral mucosa. All 665 active male workers of a metal processing factory were the study population. Semi-quantitative measures of exposure were estimated from a job exposure matrix constructed with industrial hygienist scoring and job titles. Ulcerative lesions of the oral mucosa were identified with standardized clinical dental exams. Past exposure to acid mists were positively associated with ulcerative lesions of the oral mucosa but only among workers without lip sealing (age- and alcohol consumption-adjusted prevalence ratio (PR), PRadjusted = 3.40; 90% CI: 1.48–7.85). Also in this worker group, the mixture of acid mists and acid gases was associated with ulcerative lesions of the oral mucosa limited to exposure in the past (PRadjusted = 2.83; 90% CI: 1.12–7.17). There is a positive association between acid mist or mixtures of acid mists and acid gases and ulcerative lesions of the oral mucosa only in the absence of lip sealing. The evidence of a chronic rather than acute irritative process suggests a possible step on the etiology of oral malignancies, which needs investigation. Am. J. Ind. Med. 45:238–245, 2004. © 2004 Wiley-Liss, Inc.

Standard approaches to assessing exposures for epidemiologic studies tend to concentrate resources on obtaining detailed data for each study participant at the expense of characterizing within-person variability. This paper presents some basic, generalizeable concepts concerning exposure and its variability, describes methods that can be used to analyze, describe, and understand that variability, and reviews related implications for the design and interpretation of epidemiologic studies. Insufficient attention to the balance of within- and between-person variation in exposure can reduce the efficiency of measurement efforts and attenuate estimates of exposure-disease association. Exposure variability should consequently be considered carefully in the planning, analysis, and interpretation of epidemiologic studies. Greater attention to these matters can lead to more meaningful characterization of exposure itself, and, most importantly, improve the chances that epidemiologic studies can identify and accurately characterize health hazards. Am. J. Ind. Med. 45:113–122, 2004. © 2003 Wiley-Liss, Inc.

Epidemiological studies have shown reversible declines of lung function in response to air pollution, but research on the independent effect of short-term exposure to ambient sulphur dioxide (SO2) on pulmonary function is limited. This study evaluated the association of short-term exposure to increased ambient SO2 and daily pulmonary function changes among children with and without asthma.

Research suggests that rates of occupational injury and death may be higher among self-employed workers than in the wage and salaried population. This analysis was conducted to describe the demographic and occupational characteristics, as well as injuries, activities, and occupations of self-employed workers who are fatally injured on the job. Characteristics of workers by type of employment were compared using data from the North Carolina Office of the Chief Medical Examiner, 1978–1994. Age-, activity-, and industry-specific fatality rates in self-employed workers (N = 395) were contrasted to those privately employed (N = 1,654). Highest fatal injury rates among the self-employed occurred in agriculture, retail, and transportation industries. Homicide deaths occurred more frequently among self-employed workers; deaths resulting from unintentional injuries occurred more frequently among non-self-employed workers. Elevated occupational fatality death rates among self-employed workers, especially in retail and transportation industries, provide justification for addressing work-related conditions of self-employed workers in North Carolina. Am. J. Ind. Med. 44:182–190, 2003. © 2003 Wiley-Liss, Inc.

Commercial fishing is a job characterized by long hours in an unpredictable natural environment and variable demands placed on the musculoskeletal system, requiring strength, coordination, and endurance. The focus of this project was in the quantification of the biomechanical stresses placed on the lumbar spine during the work activities of commercial crab fishermen. The Continuous Assessment of Back Stress (CABS) methodology was used to develop distributions describing the amount of time that each of the three workers on a three-man crabbing crew spend at various levels of spine stress. The results of this analysis, expressed in terms of time weighted histograms, show significant variability in the loading of the lumbar spine during regular daily activities both within and between crew members. While the captain has relatively low stress levels, the mate experiences high force (up to 30kg), dynamic exertions while pulling the crab pots from the water up into the boat and high loads (20–40kg) during the loading and unloading of the boat, while the third man experiences static awkward postures (forward flexed postures held for up to five minutes at a time) as he sorts and packs the crabs.

Contact sports have high rates of injury. Protective equipment regulations are widely used as an intervention to reduce injury risk. The purpose of this study was to investigate the injury prevention effect of regulations governing protective equipment in two full-body contact sports.

Study question: We examined whether methods for measuring exposure to airborne particles less than 10 μm in aerodynamic diameter (PM10) in the Mexico City metropolitan area give different estimates of PM10levels, and the nature of these differences, and developed a model for estimating missing PM10data for one measurement method. Methods: Government PM10measurements using two different technologies at five sites (the Sierra–Anderson PM10High-Volume Air Sampler System, Hi-Vol) (every sixth day) and the Rupprecht and Patashnik Tapered Element Oscillating Microbalance (TEOM) monitor (daily), as well as Harvard Impactor (HI) data collected for research purposes from one monitoring station were matched by day and monitoring site, then compared visually and with basic descriptive statistics. We fit linear regression models with airport visual range measurements, meteorological data, and information on other air pollutants to predict the Hi-Vol measured PM10levels for those days when direct measurements were not available. Results: We found relatively low correlations (r ranging from 0.46 to 0.63) between PM10measured with the TEOM and Hi-Vol methods, and highly variable differences (0–70 μg/m3) between the means of these measurements, depending on monitoring site. The HI measurements had a relatively high correlation with the Hi-Vol measurements (r=0.90). The models developed for the missing Hi-Vol measurements provided a series of estimated values similar to the actual Hi-Vol measurements, although the estimated series did not have high values in the range observed in the measured data. Conclusions: The differences we observed in the PM10measurements across methods in Mexico City may be important when studying health effects associated with particle exposure, evaluating method performance under conditions and operating protocols similar to those in Mexico City, and determining compliance with air quality standards. The estimated series of PM10measures may be a useful index of exposure for use in studies of the effects of air pollution on health.Journal of Exposure Analysis and Environmental Epidemiology (2002) 12, 145–156 10.1038/sj/jea/7500212

Mortality patterns were examined in a United States cohort of 138,905 male electric utility workers from five companies to help interpret previous studies of health effects in this industry. Using Poisson regression techniques, internal cohort analyses examined total mortality, cardiovascular disease, and cancer in relation to duration of employment in each of nineteen occupational categories which comprise utility operations. Relative to workers who were never involved in utility operations (e.g., administrative workers), mortality rate ratios among operations workers were higher for total mortality, cardiovascular disease, and total cancer. Lung cancer risk was consistently elevated, whereas increased mortality for other cancers was less consistent. The results of this study indicate excess risk of total mortality, cardiovascular disease, and some cancers among electric utility workers, which could be related to both occupational and non-occupational risk factors. Am. J. Ind. Med. 40:667–673, 2001. © 2001 Wiley-Liss, Inc

MARSHALL, S. W., A. E. WALLER, D. P. LOOMIS, M. FEEHAN, D. J. CHALMERS, Y. N. BIRD, and K. L. QUARRIE. Use of protective equipment in a cohort of rugby players. Med. Sci. Sports Exerc., Vol. 33, No. 12, 2001, pp. 2131–2138.

Lack of daily data on airborne particles has been a common problem in an air pollution research. To deal with this problem, a regression model was developed to estimate daily PM10 concentration using visibility in Bangkok from 1992 to 1997, based on 1092 visibility/PM10 pair-observations on low humidity days (humidity≤76.5%). Visibility was significantly and inversely associated with PM10 (r=0.71), after adjusting for minimum temperature and winter indicator variable. The R2of the model was 0.51.Journal of Exposure Analysis and Environmental Epidemiology (2001) 11, 97–102. 10.1038/sj.jea.7500148

Ethnic minorities have been omitted from many occupational health studies, despite their substantial contributions to the labor force and documented cases of high exposures in some settings. To describe the occurrence of potentially work-related cancers among African American and Latino Workers, we conducted an epidemiologic study based on death certificate data. Data were obtained from 21 states during 1985–1992. Directly adjusted proportionate mortality ratios (PMRs) and standardized mortality rate ratios (SRRs) for ages 20–64 years were computed for cancers of the lung, nasal cavity, pleura, and peritoneum, malignant melanoma and leukemia using the mortality data and population counts from the 1990 census. Proportionate mortality was generally low for both groups, but African Americans had higher than expected mortality rates for leukemia and cancers of the lung, nasal cavity, and peritoneum. Industry-specific analyses indicate excess leukemia among African American men in the rubber industry (PMR 2.08, 95% confidence interval (CI) 1.29 – 3.35), Latino men in textile (PMR 2.31, 95% CI 0.81 – 5.13) and wood industries (PMR 2.03, 95% CI 0.81 – 5.13), and Latino women in the chemical industry (PMR 2.18, 95% CI 0.59 – 8.10), among other findings. Excess cancer of the pleura and peritoneum was observed among workers with a variety of usual occupations, consistent with widespread exposure to asbestos. This study demonstrates the utility of surveillance data bases for generating basic epidemiologic information on historically neglected workers. Leads about specific workplace exposure can be followed up in more detailed studies. Am. J. Ind. Med. 38:565–575, 2000. © 2000 Wiley-Liss, Inc.

The potential association between occupational electric and magnetic field exposure and cancer is well documented in the literature, but there is uncertainty regarding a causal relation. Using data from a completed cohort study, we sought to refine the job-exposure matrix in a case-cohort analysis by regrouping jobs into more homogeneous groups, but without making additional measurements. From the original cohort, we selected the 164 men who died of leukemia, 145 men who died of brain cancer, and a random subcohort of 800 men (0.6% of the cohort). Erroneous job assignments were corrected and job groups were subdivided based on differences in work environments or tasks performed. Magnetic field exposure remained unrelated to leukemia mortality and positively associated with brain cancer mortality based on both cumulative and average magnetic field indices. Although not monotonic across the middle intervals, increased risk of brain cancer was found in relation to career exposure, with risk ratios of 1.8 (95% CI = 0.7–4.7) and 2.5 (95% CI = 1.0–6.3) in the uppermost categories for cumulative and average exposure, stronger for exposure 2–10 years past. Improvements in exposure assignment based only on reassignment of job titles to occupational categories had little impact on the measured associations of magnetic fields with leukemia or brain cancer. Am. J. Ind. Med. 38:417–425, 2000. © 2000 Wiley-Liss, Inc.

Occupational bladder cancer mortality among minority racial/ethnic groups is not well described compared to occupational bladder cancer mortality among non-minority males in the United States. Race/ethnicity- and sex-specific bladder cancer mortality (1985–1992) of workers employed in 21 states was examined using a proportionate mortality study design. Mortality of specific racial/ethnic/occupational groups was compared separately with workers in the specific occupation and with members of the specific racial/ethnic group. This study identified elevated bladder cancer mortality among African American males and females and Latino males in several occupational groups with exposure to suspected bladder carcinogens as well as among Asian males in sales (PMR = 2.13) and Asian females in the personal services industry (PMR = 5.25; CI: 1.64–16.75). Surveillance of occupational cancer risks among racial/ethnic minorities using regularly available death certificate data is facilitated when states code both usual occupation/industry and race/ethnicity. Am. J. Ind. Med. 38:90–98, 2000. © 2000 Wiley-Liss, Inc.

This paper describes the epidemiology of workplace homicides in North Carolina, with emphasis on the circumstances. Workplace homicide victims were identified by and data were abstracted from the North Carolina medical examiner system. Workplace homicide rates are highest for men, older and self-employed workers, minorities and specific occupations, especially taxi drivers. Robberies, mostly in retail settings, accounted for half of the cases, while 20% were known to involve disputes, the contexts of which differed by sex. Women were most likely to be killed by estranged partners. Preventive strategies need to address the specific contexts in which workplace homicide occurs, such as retail and taxi robberies, and law enforcement officers interacting with suspects. A workplace response to domestic violence is also needed. Other areas for future research and intervention include environmental modifications, employee screening and training, and identifying more inclusive occupational data sources. Am. J. Ind. Med. 37:629–636, 2000. © 2000 Wiley-Liss, Inc.

Historic air pollution episodes of the 1950s led to acute increases in infant mortality, and some recent epidemiologic studies suggest that infant or child mortality may still result from air pollution at current levels. To investigate the evidence for such an association, we conducted a time-series study of infant mortality in the southwestern part of Mexico City in the years 1993 to 1995 using mortality data from death registrations and air pollution measurements from a monitoring station we operated. Excess infant mortality was associated with the level of fine particles in the days before death, with the strongest association observed for the average concentration of fine particles during the period 3 to 5 days previously: a 10-μg m-3increase in the mean level of fine particles during these 3 days was associated with a 6.9 excess of infant deaths (95 confidence interval 2.5–11.3). Infant mortality was also associated with the levels of nitrogen dioxide and ozone 3 to 5 days before death, but not as consistently as with particles.

Incomplete scientific knowledge ensures that, in every study, uncertainty will enter the processes of exposure estimation and exposure-response modeling. In the light of the heated debate about the health effects of magnetic fields resulting from power production and usage, we undertook a sensitivity analysis to evaluate uncertainty related to key decisions in a previous study of brain cancer and occupational exposure to magnetic fields. The findings appeared to be relatively insensitive to most variations in the methods of exposure assessment, exposure assignment, and data analysis. The results can be visualized by defining bands of uncertainty about a best-bet estimate of the association based on our original study. These bands of methodological uncertainties were similar in magnitude to the conventional 95 confidence interval, but they rovide a measure of the potential range of systematic bias in the results, rather than reflecting statistical variability alone. The methodology employed here can be applied to other studies, and other researchers are encouraged to conduct sensitivity analysis in order to estimate methodological uncertainty as an alternative to statistical confidence intervals.

Surveillance data suggest high rates of electrocutions and fatal falls among workers in electric utility companies, who may be exposed to electric current, heights, flammable agents, and frequent motor vehicle travel. To characterize the occurrence of fatal injuries among electric utility workers, we studied workers in five electric power companies in the United States. A cohort of 127,129 men hired between 1950 and 1986 was followed through 1988. Injuries at work were identified through manual review of death certificates. The occurrence of occupational injuries was analyzed with directly adjusted rates and Poisson regression. The overall rate of fatal occupational injuries was 13.20 per 100,000 person‐years (n = 192), with 76% due to electric current, homicide, and falls from heights. Deaths were concentrated in a few groups with elevated injury rates, notably linemen (rate ratio (RR) 3.33), electricians (RR 2.79), and painters (RR 3.27). Occupations requiring daily work on elevations or frequent, direct contact with energized electrical equipment experienced markedly higher rates of fatal injury from falls and electrocutions with rate ratios of 21.8 (95% confidence interval (CI) 11.4–41.5) and 16.7 (95% CI 6.6–42.6), respectively, independent of worker age and seniority. Although fatal injury rates in this industry have declined in recent decades, significant numbers of deaths still occur. Based on the premise that all injuries are preventable, a need for continued vigilance and efforts at prevention is indicated. Am. J. Ind. Med. 35:302–309, 1999. © 1999 Wiley‐Liss, Inc.

Although annual United States occupational injury fatalities range between 7,000 and 10,400, consistent rules to determine which deaths are “occupational” do not exist. Fifty-seven North Carolina county medical examiners (MEs), responsible for more than 50 of all medical examiner cases in 1990, received our questionnaire. Fifty-three (93) responded, classifying 22 scenarios as on-the-job deaths and indicating usual classification practices and information sources. Agreement varied among the scenarios, but those involving transportation and nonpaid workers elicited particularly inconsistent responses. Fifty-six percent of medical examiners have a general rule for determining on-the-job status, but deaths associated with motor vehicles, farming, and occupations other than the decedent's usual job were classified most inconsistently. The lack of standard definitions of “job,” “work,” and “on-the-job” is apparent in classification decisions. Certain work situations need special consideration.

We studied the relationship of pleural thickening consistent with asbestos exposure to mortality, career employment in asbestos‐related jobs, and pulmonary diffusing capacity among participants in the first National Health and Nutrition Examination Survey. Three “B” readers examined chest X‐rays to identify 59 individuals with such pleural abnormalities. From 1975 to 1984, the all‐cause mortality rate ratio (RR) comparing males with and without occupational pleural thickening was 1.3 (95% C.I. 0.8–2.2). For lung cancer, the mortality RR for males was 3.0 (95% C.I. 1.0–9.1). Career asbestos work was not associated with occupational pleural thickening among men, probably because some with the condition had only short‐term exposure to asbestos. Pulmonary diffusing capacity was lower in those with occupational pleural thickening, taking smoking into account. These results suggest that individuals in the general population who have occupational pleural thickening are at risk for some of the health consequences of asbestos work, including lung cancer, even if they were not career asbestos workers.

Epidemiological studies of cancer among workers exposed to magnetic fields have yielded inconsistent results. This variability may be partly explained by differences in study methods. To assess sensitivity to such methods, data from a previous study of brain cancer and leukemia among electric power company workers were reanalyzed using alternative models, which incorporated uncertainty about the intensity of historical exposures, alternative cut points for categorizing the exposure variable for analysis, and a range of lags for describing cancer latency. Mortality rate ratios for leukemia ranged from 0.8–1.5. For brain cancer, increasing cumulative magnetic field exposure was associated with increasing mortality in virtually all models, with rate ratios between 1.3–3.4 for the most exposed workers. These rate ratios are consistent with previous analyses suggesting a 1.5–3.0‐fold increase in the risk of brain cancer but no association with leukemia, and confirm that the previous results are not dependent on arbitrary decisions in applying the exposure data. Am. J. Ind. Med. 34:49–56, 1998. © 1998 Wiley‐Liss, Inc.