Change in prevalence of asbestos-related disease among sheet metal workers 1986 to 2016

BACKGROUND

A medical screening program began in 1986 for sheet metal workers exposed to asbestos, primarily while working alongside insulators applying spray-on asbestos materials, a practice banned in 1973. Exposure continues during maintenance, renovation, and repair.

METHODS

Radiographic abnormalities among 26 397 sheet metal workers examined from 1986 to 2016 were analyzed by year of entry into the trade. Logistic regression was used to examine risk factors for parenchymal and pleural abnormalities among the overall study population and among the subcohort who entered the trade after 1973.

RESULTS

Prevalence of parenchymal disease was 17.4% for those starting work before 1950 compared with 0.8% for those starting work after 1973 (adjusted prevalence odds ratio [pOR] = 26.65, 95% confidence interval [CI] = 18.46-38.46). For each calendar year after 1973, entering the trade 1 year later was associated with an estimated 12.7% decreased odds of acquiring asbestos-related disease (adjusted pOR = 0.873, 95% CI = 0.832-0.916).

CONCLUSION

Sheet metal workers who began work after the US implemented environmental and occupational regulations develop asbestos-related disease at much reduced rates, consistent with regulatory projections made for nonmalignant asbestos-related disease by the Occupational Safety and Health Administration at the time. Cancer remains a concern among this cohort, and lung cancer screening recommendations should consider year of entry into the trade. This study highlights the importance of regulatory intervention and of continued surveillance.

Early detection of lung cancer in a population at high risk due to occupation and smoking

OBJECTIVE

The US National Comprehensive Cancer Network (NCCN) recommends two pathways for eligibility for Early Lung Cancer Detection (ELCD) programmes. Option 2 includes individuals with occupational exposures to lung carcinogens, in combination with a lesser requirement on smoking. Our objective was to determine if this algorithm resulted in a similar prevalence of lung cancer as has been found using smoking risk alone, and if so to present an approach for lung cancer screening in high-risk worker populations.

METHODS

We enrolled 1260 former workers meeting NCCN criteria, with modifications to account for occupational exposures in an ELCD programme.

RESULTS

At baseline, 1.6% had a lung cancer diagnosed, a rate similar to the National Lung Cancer Screening Trial (NLST). Among NLST participants, 59% were current smokers at the time of baseline scan or had quit smoking fewer than 15 years prior to baseline; all had a minimum of 30 pack-years of smoking. Among our population, only 24.5% were current smokers and 40.1% of our participants had smoked fewer than 30 pack-years; only 43.5% would meet entry criteria for the NLST. The most likely explanation for the high prevalence of screen-detected lung cancers in the face of a reduced risk from smoking is the addition of occupational risk factors for lung cancer.

CONCLUSION

Occupational exposures to lung carcinogens should be incorporated into criteria used for ELCD programmes, using the algorithm developed by NCCN or with an individualised risk assessment; current risk assessment tools can be modified to incorporate occupational risk.

Clinical Presentation of Peritoneal Mesothelioma

Aim

To describe the clinical presentation of peritoneal mesothelioma and its impact on survival.

Methods

Data was collected from 51 patients with peritoneal mesothelioma treated at the Washington Cancer Institute. The demographic, clinical and pathologic information were analyzed.

Results

Pain was the most common symptom (recorded in 33% of patients); increased abdominal girth occurred in 31%, increased abdominal girth and pain in 5%, and a new onset hernia in 12%. In an additional 14% of patients, a variety of other clinical findings led to the diagnosis. There was a statistically significant difference in survival by gender, weight loss and volume of disease.

Conclusions

Pain was the most common initial presenting symptom, with increased abdominal girth as a second. A more favorable prognosis occurred in women with a small disease volume.

Hearing loss among older construction workers: Updated analyses

BACKGROUND

A prior study of this construction worker population found significant noise-associated hearing loss. This follow-up study included a much larger study population and consideration of additional risk factors.

METHODS

Data included audiometry, clinical chemistry, personal history, and work history. Qualitative exposure metrics for noise and solvents were developed. Analyses compared construction workers to an internal reference group with lower exposures and an external worker population with low noise exposure.

RESULTS

Among participants (n = 19 127) an overall prevalence of hearing loss of 58% was observed, with significantly increased prevalence across all construction trades. Construction workers had significantly increased risk of hearing loss compared to reference populations, with increasing risk by work duration. Noise exposure, solvent exposure, hypertension, and smoking were significant risk factors in multivariate models.

CONCLUSIONS

Results support a causal relationship between construction trades work and hearing loss. Prevention should focus on reducing exposure to noise, solvents, and cigarette smoke.

An analysis of permanent work disability among construction sheet metal workers

BACKGROUND

Causes of permanent work disability in the sheet metal industry are not well characterized.

METHODS

Pension records were used to compare causes of disability among sheet metal workers and the U.S. working population. Subgroup analysis examined the major causes of sheet metal worker disability.

RESULTS

Musculoskeletal disorders (MSDs), circulatory disease, and injuries were leading causes of sheet metal worker disability (47.2%, 13.7%, 10.9% of awards, respectively). Award distribution differed from the U.S. working population (P < 0.0001); MSDs and injuries accounted for higher proportions of sheet metal worker awards, particularly at spine, shoulder, and knee.

CONCLUSIONS

Higher proportions of awards caused by MSD or injury among sheet metal workers may reflect higher rates of work-related injuries and MSDs, a high likelihood of disability with construction work given the same impairment, or higher prevalence of other conditions in the general population. Prevention requires task-specific ergonomic innovations and proven participatory interventions.

Best practices for health and safety technology transfer in construction

BACKGROUND

Construction continues to be a dangerous industry, yet solutions that would prevent injury and illness do exist. Prevention of injury and illness among construction workers requires dissemination, adoption, and implementation of these effective interventions, or "research to practice" (r2p).

METHODS

CPWR recruited participants with experience and insight into effective methods for diffusion of health and safety technologies in this industry for a symposium with 3 group sessions and 3 breakout groups. The organizers reviewed session notes and identified 141 recommendations, which were then assigned to 13 over-arching themes.

RESULTS

Recommendations included a guide for researchers on patenting and licensing, a business case model, and in-depth case studies including development, testing, manufacturing, marketing, and diffusion.

CONCLUSIONS

A more comprehensive understanding of the health and safety technology transfer landscape, the various actors, and their motivators and goals will help to foster the successful commercialization and diffusion of health and safety innovations.

Creating a climate for ergonomic changes in the construction industry

BACKGROUND

Ergonomic solutions that have gained acceptance in other industries are often considered not applicable to a construction work environment, even though the industry is characterized by high physical work demands.

METHODS

We conducted 50 key informant interviews with 23 contractor representatives and 27 union staff, plus 4 focus groups with a total of 48 workers.

RESULTS

Many workers hold the belief that WMSDs are inevitable as part of the job, and did not consistently believe that changing the nature of the work could prevent that injury or pain. The interviewees reported limited availability and accessibility of tested and effective tools that both reduce physical demand and also get the job done efficiently and effectively. Yet for each major obstacle to implementation of ergonomics in the industry identified, the construction professionals we interviewed offered a variety of solutions.

CONCLUSIONS

Contractors, unions, and workers need to work together to find actions that work within the parameters of the current economic environment.

Promoting integrated approaches to reducing health inequities among low-income workers: applying a social ecological framework

BACKGROUND

Nearly one of every three workers in the United States is low-income. Low-income populations have a lower life expectancy and greater rates of chronic diseases compared to those with higher incomes. Low- income workers face hazards in their workplaces as well as in their communities. Developing integrated public health programs that address these combined health hazards, especially the interaction of occupational and non-occupational risk factors, can promote greater health equity.

METHODS

We apply a social-ecological perspective in considering ways to improve the health of the low-income working population through integrated health protection and health promotion programs initiated in four different settings: the worksite, state and local health departments, community health centers, and community-based organizations.

RESULTS

Examples of successful approaches to developing integrated programs are presented in each of these settings. These examples illustrate several complementary venues for public health programs that consider the complex interplay between work-related and non work-related factors, that integrate health protection with health promotion and that are delivered at multiple levels to improve health for low-income workers.

CONCLUSIONS

Whether at the workplace or in the community, employers, workers, labor and community advocates, in partnership with public health practitioners, can deliver comprehensive and integrated health protection and health promotion programs. Recommendations for improved research, training, and coordination among health departments, health practitioners, worksites and community organizations are proposed.

Asbestos Exposure Causes Mesothelioma, But Not This Asbestos Exposure: An Amicus Brief to the Michigan Supreme Court

Manufacturers of asbestos brakes, supported by many manufacturing and insurance industry amicus curie, requested the Michigan Supreme Court to dismiss testimony of an expert regarding the ability of asbestos dust from brakes to cause mesothelioma as "junk science". Scientists are concerned with the sweeping and unequivocal claims that any conclusion that asbestos from brakes caused a signature asbestos-related disease in a particular person must be "junk science". The manufacturers' sweeping pronouncements are what veer from accepted, reliable mainstream scientific methods and conclusions. This article outlines the evidence supporting the conclusion that asbestos from brakes can and does cause mesothelioma, and describes the defendants' attempts to fabricate doubt about this conclusion.

Beryllium disease among construction trade workers at Department of Energy nuclear sites

BACKGROUND

A medical surveillance program was developed to identify current and former construction workers at significant risk for beryllium related disease from work at the DOE nuclear weapons facilities, and to improve surveillance among beryllium exposed workers.

METHODS

Medical examinations included a medical history and a beryllium blood lymphocyte proliferation test (BeLPT). Stratified and multivariate logistic regression analyses were used to explore the risk of disease by age, race, trade, and reported work in buildings where beryllium was used. After adjusting for covariates, the risk of BeS was significantly higher among boilermakers, roofers, and sheet metal workers, as suggested in the stratified analyses. Workers identified as sensitized to beryllium were interviewed to determine whether they had been subsequently diagnosed with chronic beryllium disease.

RESULTS

Between 1998 and December 31, 2010 13,810 workers received a BeLPT through the BTMed program; 189 (1.4%) were sensitized to beryllium, and 28 reported that they had had a compensation claim accepted for CBD.

CONCLUSIONS

These data on former construction workers gives us additional information about the predictive value of the blood BeLPT test for detection of CBD in populations with lower total lifetime exposures and more remote exposures than that experienced by current workers in beryllium machining operations. Through this surveillance program we have identified routes of exposures to beryllium and worked with DOE site personnel to identity and mitigate those exposures which still exist, as well as helping to focus attention on the risk for beryllium exposure among current demolition workers at these facilities.

Preventing chronic disease in the workplace: a workshop report and recommendations

Chronic disease is the leading cause of death in the United States. Risk factors and work conditions can be addressed through health promotion aimed at improving individual health behaviors; health protection, including occupational safety and health interventions; and efforts to support the work-family interface. Responding to the need to address chronic disease at worksites, the National Institutes of Health and the Centers for Disease Control and Prevention convened a workshop to identify research priorities to advance knowledge and implementation of effective strategies to reduce chronic disease risk. Workshop participants outlined a conceptual framework and corresponding research agenda to address chronic disease prevention by integrating health promotion and health protection in the workplace.

Impact of musculoskeletal and medical conditions on disability retirement-a longitudinal study among construction roofers

BACKGROUND

To assess the intersection of work demands, chronic medical and musculoskeletal conditions, aging, and disability, we initiated a longitudinal study of construction roofers who were current union members between the ages of 40 and 59.

METHODS

Participants were asked about the presence of medical conditions and musculoskeletal disorders; the Work Limitations Questionnaire, the SF-12, and other validated assessments of social and economic impact of injury were included.

RESULTS

Factors at baseline that predicted leaving for a health-related reason were older age, lower physical functioning, work limitations, and having missed work. Those who left roofing for a health-related reason were much more likely to have a lower economic score at the 1 year interview.

CONCLUSIONS

Medical and musculoskeletal conditions are strongly associated with work limitation, missed work, and reduced physical functioning; these factors are also associated with premature departure from the workforce.

Validity assessment of self-reported construction tasks

This study assessed agreement between workers' and observers' daily estimates of exposure to construction work tasks. The ultimate aim was to develop a valid method and instrument for the collection of self-reported data on duration of exposure to a priori identified work tasks for use in characterizing exposure in settings with substantial task variability. Forty-nine shop workers and 52 construction site sheet metal workers were observed for up to 3 full workdays. Observers sampled approximately 25% of each worker's day, recording the work performed from a prespecified list of tasks. Each participant completed a daily questionnaire, indicating the tasks he or she performed that day and time spent on each task. Shop workers tended to specialize in particular tasks, while at the construction site, the workers' tasks reflected substantial day-to-day variability. Agreement between worker and observer estimates was generally better for major shop tasks (with intraclass correlation coefficients [ICCs] ranging from 0.52 to 0.85), than for major construction site tasks (with ICCs ranging from 0.36 to 0.64). Workers tended to overestimate the amount of time spent at tasks of longer duration and to underestimate time spent at short-duration tasks. Rank order analysis of time spent on task revealed fairly high agreement. Agreement was acceptable for shop-based work, which has less day-to-day variability than construction site work. Overall, however, the data suggest that, for highly variable work, the use of task as the unit of exposure does not improve recall over assessment approaches focusing on questions about posture and material handling.

Developments in asbestos cancer risk assessment

BACKGROUND

Efforts have been made for 25 years to develop asbestos risk assessments that provide valid information about workplace and community cancer risks. Mathematical models have been applied to a group of workplace epidemiology studies to describe the relationships between exposure and risk. EPA's most recent proposed method was presented at a public meeting in July 2008.

METHODS

Risk assessments prepared by USEPA, OSHA, and NIOSH since 1972 were reviewed, along with related literature.

RESULTS AND CONCLUSIONS

None of the efforts to use statistical models to characterize relative cancer potencies for asbestos fiber types and sizes have been able to overcome limitations of the exposure data. Resulting uncertainties have been so great that these estimates should not be used to drive occupational and environmental health policy. The EPA has now rejected and discontinued work on its proposed methods for estimating potency factors. Future efforts will require new methods and more precise and reliable exposure assessments. However, while there may be genuine need for such work, a more pressing priority with regard to the six regulated forms of asbestos and other asbestiform fibers is to ban their production and use.

Mortality of older construction and craft workers employed at Department of Energy (DOE) nuclear sites

BACKGROUND

The U.S. Department of Energy (DOE) established medical screening programs at the Hanford Nuclear Reservation, Oak Ridge Reservation, the Savannah River Site, and the Amchitka site starting in 1996. Workers participating in these programs have been followed to determine their vital status and mortality experience through December 31, 2004.

METHODS

A cohort of 8,976 former construction workers from Hanford, Savannah River, Oak Ridge, and Amchitka was followed using the National Death Index through December 31, 2004, to ascertain vital status and causes of death. Cause-specific standardized mortality ratios (SMRs) were calculated based on US death rates.

RESULTS

Six hundred and seventy-four deaths occurred in this cohort and overall mortality was slightly less than expected (SMR = 0.93, 95% CI = 0.86-1.01), indicating a "healthy worker effect." However, significantly excess mortality was observed for all cancers (SMR = 1.28, 95% CI = 1.13-1.45), lung cancer (SMR = 1.54, 95% CI = 1.24-1.87), mesothelioma (SMR = 5.93, 95% CI = 2.56-11.68), and asbestosis (SMR = 33.89, 95% CI = 18.03-57.95). Non-Hodgkin's lymphoma was in excess at Oak Ridge and multiple myeloma was in excess at Hanford. Chronic obstructive pulmonary disease (COPD) was significantly elevated among workers at the Savannah River Site (SMR = 1.92, 95% CI = 1.02-3.29).

CONCLUSIONS

DOE construction workers at these four sites were found to have significantly excess risk for combined cancer sites included in the Department of Labor' Energy Employees Occupational Illness Compensation Program (EEOCIPA). Asbestos-related cancers were significantly elevated.

Asbestos-related disease among sheet metal workers 1986-2004: radiographic changes over time

BACKGROUND

In 1985, the Sheet Metal Workers International Association and the Sheet Metal and Air Conditioning National Association formed The Sheet Metal Occupational Health Institute Trust (SMOHIT) to examine the health hazards of the sheet metal industry. Between 1986 and 2004 18,211 individuals were examined. At the time of the first examination 9.6% of all participants (1,745) had findings consistent with parenchymal disease (ILO > 1/0), and 21% (3,827) had pleural scarring.

METHODS

2181-Two thousand hundred eighty-one who had no radiographic evidence of pneumoconiosis on baseline examination underwent a second examination.

RESULTS

By the second examination, 5.3% had developed parenchymal disease on chest radiograph; an additional 12.4% had developed pleural scarring without parenchymal disease. Factors that predicted new cases of pneumoconiosis on radiograph were the calendar year the worker entered the sheet metal trade, smoking, and shipyard work. Forty-seven percent of those smoking at the time of initial exam reported having quit smoking by the second examination.

CONCLUSIONS

Asbestosis is still occurring 50 years after first exposure. Exposed workers benefit from medical screening programs that incorporate smoking cessation.

Age, work limitations and physical functioning among construction roofers

BACKGROUND

To investigate the intersection of aging with work limitations, chronic medical and musculoskeletal conditions, and physical functioning we undertook a cross-sectional study of U.S. construction roofers who were current union members between the ages of 40 and 59.

METHODS

Participants were asked about the presence of medical conditions and musculoskeletal disorders (MSDs); the Work Limitations Questionnaire, the SF-12, and other validated assessments of social and economic impact of injury were included.

RESULTS

Sixty-nine percent had at least one of these conditions in the previous two years; 31% missed work. Workers with medical and musculoskeletal conditions were older, had the highest prevalence of work activity limitations, and had the lowest SF-12 scores.

CONCLUSIONS

Older age was associated with the presence of a medical condition, and with reduced physical functioning. Medical and musculoskeletal conditions were strongly associated with work limitation, missed work, and reduced physical functioning. Older workers may be at higher risk of disability retirement compared to younger workers with similar medical conditions and work limitations.

Is the apparent decrease in injury and illness rates in construction the result of changes in reporting?

Injury rates in all industries and in construction in particular have been declining. Inconsistencies in the information suggest some of the apparent decrease may be due to changes in the ways injuries are treated, misclassification of employees, or underreporting. Lost-time injury rates for the largest construction employers declined by as much as 92% between 1988 and 1999. Yet the rate for cases with restricted work activity actually increased from 0.7 to 1.2 per 100 full-time workers between 1990 and 2000, and fatalities among construction workers remain high. In Massachusetts, at least 14% of construction employers misclassified workers as independent contractors, with the effect that injuries to these workers are not recordable. Studies that compare OSHA logs with other data sources find that the OSHA logs do not include a significant proportion of injuries and illnesses identified elsewhere.

Change in Prevalence of Asbestos-Related Disease Among Sheet Metal Workers 1986 to 2004

In 1985, the Sheet Metal Workers International Association and the Sheet Metal and Air Conditioning National Association formed The Sheet Metal Occupational Health Institute Trust to examine the health hazards of the sheet metal industry in the United States and Canada. Between 1986 and 2004, 18,211 individuals were examined. The mean age of this cohort was 57.9 years, and the participants had worked for a mean (+/- SD) duration of 32.9 +/- 6 years in the sheet metal trade. Twenty-three percent of participants were current smokers, 49% were former smokers, and 28% were never-smokers. A total of 9.6% of participants (1,745 participants) had findings that were consistent with parenchymal disease (International Labor Organization [ILO] score, >/= 1/0); 60% of those with an ILO score >/= 1/0 were classified as 1/0, 34% as 1/1 to 1/2, and 6% as >/= 2/1. A total of 21% of participants (3,827 participants) had pleural scarring. There was a lower prevalence of nonmalignant asbestos-related disease among those who began to work after 1970, when compared to workers who began to work before 1949; those who began to work between 1950 and 1969 had a prevalence between the other two groups. The strongest predictor of both parenchymal and pleural disease on a chest radiograph was the calendar year in which the worker began sheet metal work; work in a shipyard was also an important risk. The results of this study suggest that the efforts to reduce asbestos exposure in the 1980s through strengthened Occupational Safety and Health Administration regulation have had a positive public health impact.

Asbestos and peritoneal mesothelioma among college-educated men

The proportion of peritoneal mesotheliomas among all mesotheliomas has been decreasing, leading some to suggest that peritoneal mesothelioma occurs only after high levels of exposure to asbestos. To investigate the relationship between asbestos exposure and the development of peritoneal mesothelioma, a case-control study examined 40 cases of primary peritoneal mesothelioma from a single institution. This series differed from previous reports in that 75% of the cases and controls had attended college. Results show an odds ratio of 6.6 for asbestos exposure among this group of primary peritoneal mesothelioma cases with relatively slight asbestos exposures.

Occupational injuries among construction workers treated in a major metropolitan emergency department in the United States

OBJECTIVES

The aim of this study was to profile construction workers' injuries for more information about the causes of nonfatal construction worker injuries and identify injury trends for further investigations and prevention programs.

METHODS

An injury-tracking program for emergency departments was established in 1990 to gather the data needed for the study. Profiles were obtained for 2916 construction workers' injuries that were identified on hospital registration forms at the George Washington University Emergency Department in Washington, DC, from November 1990 through October 1997. Laborers and construction workers who did not specify a trade were combined, and together they made up the largest group--29% of the injured workers.

RESULTS

The leading cause of injury was contact with cutting or piercing objects-most often pieces of metal, razors, knives, power tools, and nails. Workers striking against objects or being struck by objects (including falling objects) accounted for the second-largest group of injuries, and the third leading injury circumstance was falling--either from a height or on the same level. Detailed injury statistics are presented by trade, showing patterns of injury that reflect tasks of these trades and which injuries predominated in each trade. Although many previous reports have described construction workers' injuries, very few have provided detailed data by trade.

CONCLUSIONS

The details presented in this analysis allow for a better understanding of the injury circumstances and provide a starting point for injury prevention programs.

A review of peritoneal mesothelioma at the Washington Cancer Institute

This article reviews a single institution's experience with 68 patients (21 females, 47 males) prospectively treated over the last 2 decades with an aggressive local-regional approach, combining maximal cytoreductive surgery with heated intraoperative intraperitoneal chemotherapy and early postoperative intraperitoneal chemotherapy. This multimodality treatment has resulted in a median survival of 67 months. Female patients had a significantly better prognosis than males. The other significant predictive factors of survival were: age, diagnosis by incidental findings, tumor extent, pathology, and completeness of cytoreduction.

Injury surveillance in construction: what is an "injury", anyway?

BACKGROUND

Over the last decade, there has been a decline in injuries with days away from work in construction, associated with an increase in injuries with restricted work activity only.

METHODS

We abstracted demographics, diagnosis, cause-of-injury, and hospital discharge information for 481 workers from one large construction project treated in an urban Emergency Department (ED). The project safety team provided data on all injuries from this site, including first aid cases.

RESULTS

This site had fewer injuries with days away from work than expected from national rates. Two hundred and fifty-six injuries were reported on the OSHA log, and of those 93 entailed days away from work; 1,515 injuries were considered first aid/medical only. We used a sample of the data to estimate that the site classified as "recordable" 128 of the 481 ED-treated injuries from this site (27%).

CONCLUSIONS

The pattern of injury varies depending on the subset of injuries examined. Lost time injuries, as reported in BLS data, record fewer lacerations and eye injuries, and more strains and sprains. No one surveillance system presents the full spectrum of occupational injury. Tracking all injuries allow early recognition of injury risks, and therefore can lead to more effective prevention.

Does nitric oxide contribute to the basal vasodilation of pregnancy in conscious rabbits?

Pregnancy produces marked systemic vasodilation, but the mechanism is unknown. Experiments were performed in conscious rabbits to test the hypotheses that increased nitric oxide (NO) production contributes to the increased vascular conductance, but that the contribution varies among vascular beds. Rabbits were instrumented with aortic and vena caval catheters and ultrasonic flow probes implanted around the ascending aorta, superior mesenteric artery, terminal aorta, and/or a femoral artery. Hemodynamic responses to intravenous injection of N(omega)-nitro-L-arginine (L-NA; 20 mg/kg or increasing doses of 2, 5, 10, 15, and 20 mg/kg) were determined in rabbits first before pregnancy (NP) and then at the end of gestation (P). L-NA produced similar increases in arterial pressure between groups, but the following responses were larger (P < 0.05) when the rabbits were pregnant: 1) decreases in total peripheral conductance [-3.7 +/- 0.3 (NP), -5.0 +/- 0.5 (P) ml x min(-1) x mmHg(-1)], 2) decreases in mesenteric conductance [-0.47 +/- 0.05 (NP), -0.63 +/- 0.07 (P) ml x min(-1) x mmHg(-1)], 3) decreases in terminal aortic conductance [-0.43 +/- 0.05 (NP), -0.95 +/- 0.19 ml x min(-1) x mmHg(-1) (P)], and 4) decreases in heart rate [-41 +/- 4 (NP), -62 +/- 5 beats/min (P)]. Nevertheless, total peripheral and terminal aortic conductances remained elevated in the pregnant rabbits (P < 0.05) after L-NA. Furthermore, decreases in cardiac output and femoral conductance were not different between the reproductive states. We conclude that the contribution of NO to vascular tone increases during pregnancy, but only in some vascular beds. Moreover, the data support a role for NO in the pregnancy-induced increase in basal heart rate. Finally, unknown factors in addition to NO must also underlie the basal vasodilation observed during pregnancy.

Injury surveillance in construction: eye injuries

Occupational eye injuries are both common and preventable. About 20% of occupational eye injuries occur in construction. To investigate the nature of eye injuries among construction workers, we analyzed a large data set of construction worker injuries. In addition, we interviewed 62 workers with eye injuries to further explore circumstances of eye injury and workers' attitudes and behavior toward the use of eye protection. Eleven percent (363 cases) of the 3,390 construction workers in our data set were treated for eye injuries. Welders, plumbers, insulators, painters/glaziers, supervisors, and electricians had a higher proportion of all injuries due to eye injuries than other trades. Nearly half of the diagnoses were abrasions (46%) followed by foreign objects or splash in the eye (29%), conjunctivitis (10%), and burns (5%). In the interviews with 62 workers, we found that employers very frequently required eye protection for all tasks or for high-risk tasks, and workers report wearing eye protection regularly. However, most did not wear eye protection with top and side shields; if we believe the injuries occurred because a particle or liquid passed between the glasses and the workers' faces, increased use of goggles or full shields would have prevented two-thirds of this group of injuries.

Role of angiotensin II in altered baroreflex function of conscious rabbits during late pregnancy

OBJECTIVE

Pregnancy alters baroreflex control of heart rate in conscious rabbits, but the mechanism for this action is unknown. This study tested the hypothesis that endogenous angiotensin II is the mediator.

STUDY DESIGN

To test this hypothesis the baroreflex relationship between arterial pressure and heart rate in conscious rabbits was determined before and after administration of the angiotensin II AT1 receptor antagonist losartan (n = 7) before pregnancy and at the end of gestation.

RESULTS

Pregnancy decreased mean arterial pressure, increased heart rate, and modified the reflex by shifting the mean arterial pressure-heart rate relationship to a lower pressure level, by increasing minimum heart rate, and by decreasing baroreflex gain (P < .05). Before pregnancy, losartan decreased baroreflex gain but had no other effect on reflex function. In contrast, during late gestation losartan further decreased mean arterial pressure, further decreased reflex gain, decreased maximum heart rate, and shifted the curve to a lower mean arterial pressure level (P < .05).

CONCLUSION

These results suggest that in conscious rabbits during pregnancy endogenous angiotensin II contributes to hypotension-induced tachycardia but does not decrease reflex gain or elevate minimum heart rate.

Injury surveillance in construction: injuries to laborers

Construction is one of the largest industries in the United States, employing over 7.5 million people. It accounts for 3 times as many accidents as might be expected on a per capita basis. Laborers represent one of 15 job classifications participating in this industry. They have a higher risk of death or injury from a number of causes than do other construction workers.

Women in construction: occupational health and working conditions

Construction is one of the largest industries in the United States, employing 7.6 million workers, or about 5% of the US work force. More women have taken jobs in the construction industry over the last two decades, as they have in other nontraditional industries. In 1997, there were 8.1 million construction workers, of whom 781,000 (9%) were women. Approximately 2% of those were employed as skilled tradeswomen. There is no disputing that construction work is dangerous. Seventeen percent of all fatal on-the-job injuries occur in construction, which is about three times its 6% share of total employment. In this paper, we review the medical literature on the safety and health hazards for women working in the construction industry. Women have a different pattern of fatal injuries and some differences in patterns of nonfatal injuries than men and report unique problems and concerns related to working in this industry.

Injury and employment patterns among Hispanic construction workers

This article describes non-fatal injuries among Hispanic construction workers treated at an emergency department from 1990 to 1998. Medical and interview data were analyzed to evaluate and explain the workers' apparently inflated risk of injury. The majority of the injured Hispanic workers were employed in the less-skilled trades. Compared with other injured workers, Hispanics had a higher proportion of serious injuries and were disadvantaged in terms of training and union status. With the exception of union status, these differences largely disappeared after controlling for trade. The physical, financial, and emotional consequences were more apparent 1 year later for injured Hispanics, even after controlling for trade. These observations suggest that minority status is a predictor of trade and that trade is a predictor of injury risk. In addition to reducing injury hazards, interventions should address the limited employment and union membership options that are available to minority workers in the construction industry.

Chronic symptoms in construction workers treated for musculoskeletal injuries

BACKGROUND

Soft tissue musculoskeletal injuries make up a high proportion of all work-related injuries in construction. Data from Workers' Compensation claims indicate that strains and sprains are the leading compensable injury for construction workers. This study describes the consequences of soft tissue musculoskeletal injuries for construction workers, and assesses the persistence of symptoms after an injury and the impact of that injury on return to work.

METHODS

Through an Emergency Department surveillance system [Hunting et al., 1994a], we recorded 176 construction worker visits, from 5/01/93 through 2/28/95, for strains, sprains, joint injury or pain, tendinitis, dislocations, hernias, or other musculoskeletal injuries excluding fractures. Telephone interviews were conducted several months after workers had visited the emergency room for a musculoskeletal injury.

RESULTS

Seventy individuals were interviewed about the long-term impacts of 72 incidents that had resulted in work-related musculoskeletal injuries. For 46 (62%) of the 74 diagnoses, problems continued beyond two months. The likelihood of problems continuing more than two months varied considerably by body location of injury. Hispanic workers and older workers were more likely to have continuing symptoms. Eleven of the 45 construction workers with symptoms persisting longer than two months were not employed at the time of the interview. Only 11 of the 45 workers with ongoing symptoms told us that modifications had been made to their jobs to accommodate their symptoms. About one-quarter of these 45 subjects reported substantial effects on home or work life.

CONCLUSIONS

Acute musculoskeletal injuries in construction workers frequently result in chronic symptoms, and those with chronic symptoms report substantial effects of the injury on their quality of life. Job accommodations were made in a minority of these injuries. These findings point to the need for heightened efforts for injury prevention in this industry.

Regional conductance changes during hemorrhage in pregnant and nonpregnant conscious rabbits

Late pregnant (P) conscious rabbits are less able to maintain arterial pressure during hemorrhage than nonpregnant (NP) animals. This study tested the hypothesis that the difference is due in part to less reflex vasoconstriction when the rabbits are P. Rabbits (n = 14) were instrumented with arterial and venous catheters as well as ultrasonic flow probes around the superior mesenteric, renal, and/or terminal aortic arteries. Pregnancy increased (P < 0.05) blood volume [235 +/- 5 (P) vs. 171 +/- 3 (NP) ml], terminal aortic conductance [1.88 +/- 0.11 (P) vs. 0.98 +/- 0.06 (NP) ml. min(-1). mmHg(-1)], mesenteric conductance [1.20 +/- 0.19 (P) vs. 0.80 +/- 0. 05 (NP) ml. min(-1). mmHg(-1)], and heart rate [191 +/- 4 (P) vs. 162 +/- 3 (NP) beats/min] and decreased arterial pressure [59 +/- 1 (P) vs. 67 +/- 2 (NP) mmHg; P < 0.05]. Renal conductance was unaltered. The rabbits were bled in both the NP and P states at 2% of the initial blood volume per minute until arterial pressure fell below 45 mmHg. Arterial pressure fell with less blood loss in P rabbits [28 +/- 2% (P) vs. 39 +/- 2% (NP) of initial blood volume; P < 0.001]. Terminal aortic conductance decreased (P < 0.001) before the pressure fall in both groups, but the response was reduced in P rabbits. Mesenteric and renal conductances did not change in either group before the blood pressure fall. During the pressure fall, terminal aortic conductance increased (P < 0.05) only in NP rabbits. Mesenteric conductance increased in both groups. In summary, rabbits in late gestation are less able to maintain arterial pressure during hemorrhage, at least in part because of reduced vasoconstriction in tissues perfused by the terminal aorta.

Surveillance of construction worker injuries: the utility of trade-specific analysis

Construction is a dangerous industry, with high rates of both fatal and nonfatal injuries. To learn more about the causes of nonfatal construction worker injuries, and to identify injury cases for further work site-based investigations or prevention programs, we established an emergency department-based surveillance program in November 1990. This article describes circumstances of injury, diagnoses, and demographic characteristics of injured construction workers for 2,791 cases identified through mid-August, 1997. Lacerations and strains and sprains were the most frequent diagnoses; cutting and piercing objects were the leading causes of injury among all construction workers, followed by falls and overexertion. Because of the variety of work performed in this industry, more detailed injury descriptions, by trade, are most useful for thinking about injury prevention. To illustrate this, we profile injury patterns among workers from four specific trades: carpenters, electricians, plumbers, and ironworkers. Areas of concern highlighted by the trade-specific analyses include eye injuries among plumbers; falls from ladders among electricians and plumbers; slips, trips, and falls on the same level among ironworkers; electrical exposure among electricians; and, amputations among carpenters.

Fatal and non-fatal injuries from vessels under air pressure in construction

Using a surveillance system that captures data on construction workers treated in an urban emergency department, we identified a series of injuries caused by vessels and tools under air pressure. We describe those six cases, as well as similar cases found in the Census of Fatal Occupational Injuries; we also review data from the National Surveillance for Traumatic Occupational Fatalities database and data from the Bureau of Labor Statistics. Among the injuries and deaths for which we had good case descriptions, the majority would have been prevented by adherence to existing Occupational Safety and Health Administration standards in the construction industry.