Cancer mortality in U.S. counties with shipyard industries during World War II

Respiratory cancer mortality, 1950–1969, was consistently high in U.S. counties where shipyards were engaged in the construction and repair of large naval and cargo vessels during World War II. Over three-fourths of the shipyard counties had elevated rates (in comparison to rates in counties of similar population size in the same region of the country) for lung and laryngeal cancer among white males, with the excess particularly evident in the South. Mortality from lung cancer was high also among white females, and the rate of increase in both sexes was greater than recorded nationally. In addition, rates for oropharyngeal, esophageal, and gastric cancers tended to be elevated in the shipyard counties, but mortality from other tumors was roughly comparable to national levels. A causal relation to asbestos exposures in shipyards cannot be inferred from this correlational analysis, but the unusual mortality patterns underscore the need for broadly based analytic studies to evaluate the risk of cancer in persons with wartime shipyard employment.     

Cancer mortality in U.S. counties with hazardous waste sites and ground water pollution

Since the late 1950s, more than 750 million tons of toxic chemical wastes have been discarded in an estimated 30,000 to 50,000 hazardous waste sites (HWSs). Uncontrolled discarding of chemical wastes creates the potential for risks to human health. Utilizing the National Priorities Listing (NPL) of hazardous waste sites developed by the United States Environmental Protection Agency (EPA), this study identified 593 waste sites in 339 U.S. counties in 49 states with analytical evidence of contaminated ground drinking water providing a sole source water supply. For each identified county, age-adjusted, site-specific cancer mortality rates for 13 major sites for the decade 1970-1979, for white males and females, were extracted from U.S. Cancer Mortality and Trends 1950-1979. Also, HWS and non-HWS counties that showed excess numbers of deaths were enumerated for each cancer selected. Significant associations (p less than .002) between excess deaths and all HWS counties were shown for cancers of the lung, bladder, esophagus, stomach, large intestine, and rectum for white males; and for cancers of the lung, breast, bladder, stomach, large intestine, and rectum for white females when compared to all non-HWS counties. There were no consistent geographical patterns that suggested a broad distribution of gastrointestinal cancers associated with HWSs throughout the United States, although we did identify a cluster of excess gastrointestinal cancers in counties within states located in EPA Region 3 (Delaware, Maryland, Pennsylvania, Virginia, West Virginia).(ABSTRACT TRUNCATED AT 250 WORDS)     

Air pollution and daily mortality in three U.S. counties

I used generalized additive models to analyze the time-series of daily total nonaccidental and cause-specific (cardiovascular, cerebrovascular, and chronic obstructive pulmonary disease) deaths over the period 1987-1995 in three major U.S. metropolitan areas: Cook County, Los Angeles County, and Maricopa County. In all three counties I had monitoring information on particulate matter [less than/equal to] 10 microm (PM(10)), carbon monoxide, sulfur dioxide, nitrogen dioxide, and ozone. In Los Angeles, monitoring information on particulate matter [less than/equal to] 2.5 microm (PM(2.5)) was available as well. I present the results of both single and multi-pollutant analyses. Air pollution was associated with each of the mortality end points. With respect to the individual components of the pollution mix, the results indicate considerable heterogeneity of air pollution effects in the different geographic locations. In general, the gases, particularly CO, but not ozone, were much more strongly associated with mortality than was particulate matter. This association was particularly striking in Los Angeles County.     

Selenium in forage crops and cancer mortality in U.S. counties

The potential protective effect of selenium status on the risk of developing cancer has been examined in animal and epidemiologic studies. This ecological study investigated the association between U.S. county forage selenium status and site- and sex-specific county cancer mortality rates (1950-1969) using weighted least squares regression. Consistent, significant (p less than .01) inverse associations were observed for cancers of the lung, rectum, bladder, esophagus, and cervix in a model limited to rural counties and for cancers of the lung, breast, rectum, bladder, esophagus, and corpus uteri in a model of all counties. No consistent significant positive associations were observed in the rural county models. This remarkable degree of consistency for the inverse associations strengthens the likelihood of a causal relationship between low selenium status and an increased risk of cancer mortality.     

Cancer mortality among women employed in fast-growing U.S. occupations.

Our study examined cancer mortality before the age of 65 for women employed in the fastest growing and/or traditionally female occupations. Analysis of mortality data from 28 U.S. states for 1984-1995 revealed elevated proportionate cancer mortality ratios (PCMRs). The highest PCMRs observed were thyroid cancer among health aides, lymphatic and multiple myeloma among computer programmers, and brain cancer among actresses and directresses. Some of the excess mortality occurred for occupations that have been previously cited. These included elevated breast and ovarian cancer among teachers, Hodgkin's disease among hairdressers and cosmetologists, and thyroid cancer among health aides and therapists. A few of the associations were new, i.e., had not been previously observed. These included cancer of the connective tissue and lymphatic system among computer programmers, ovarian cancer and leukemia among secretaries, and lymphatic cancer and multiple myeloma among child care workers. These findings should be further investigated with epidemiologic and environmental studies.     

Simultaneous smoothing and adjusting mortality rates in U.S. counties: melanoma in white females and white males

Detecting patterns in health-related data for geographic areas is facilitated with the use of exploratory methods, especially smoothing. In addition, these data often must be adjusted for known prognostic factors such as age and gender. The analysis in this paper focuses on mortality rates due to malignant melanoma in White males and White females; these data are adjusted for both age and latitude, separately for males and females, and then smoothed using (a) a non-linear smoother known as weighted head-banging, and (b) a new method that incorporates the adjustment and the smoothing simultaneously. Maps of the continental United States show regions of high rates, even after having adjusted for age and latitude, and suggest the possibility of other variables that may influence the rates.     

Family planning clinic services in U.S. counties, 1983

Organized family planning clinics are a major source of contraceptive services for low-income women, who are less likely than higher income women to be using a contraceptive method. A 1983 study estimated that 9.5 million U.S. women with family incomes below 150 percent of poverty were at risk of unintended pregnancy, and identified a network of 5,106 clinics providing them with services. Seventy-six percent of all counties in the United States have organized clinics that offer family planning services; almost all of those without services are nonmetropolitan counties. An estimated 52 percent of low-income women at risk of unintended pregnancy were served by organized family planning clinics in 1983, while the rest either went unserved or sought care elsewhere. Ten percent of low-income women not served by clinics live in counties that have no family planning clinics, but 67 percent live in counties where existing clinics reach fewer than half of potential low-income patients. More sites may be needed, particularly in counties without clinics, to effectively serve low-income women at risk of unintended pregnancy. However, since the majority of unserved women live in counties where at least one clinic exists, coverage might be improved through increased accessibility and outreach.     

Using quantile regression to examine the effects of inequality across the mortality distribution in the U.S. counties

The U.S. has experienced a resurgence of income inequality in the past decades. The evidence regarding the mortality implications of this phenomenon has been mixed. This study employs a rarely used method in mortality research, quantile regression (QR), to provide insight into the ongoing debate of whether income inequality is a determinant of mortality and to investigate the varying relationship between inequality and mortality throughout the mortality distribution. Analyzing a U.S. dataset where the five-year (1998-2002) average mortality rates were combined with other county-level covariates, we found that the association between inequality and mortality was not constant throughout the mortality distribution and the impact of inequality on mortality steadily increased until the 80th percentile. When accounting for all potential confounders, inequality was significantly and positively related to mortality; however, this inequality-mortality relationship did not hold across the mortality distribution. A series of Wald tests confirmed this varying inequality-mortality relationship, especially between the lower and upper tails. The large variation in the estimated coefficients of the Gini index suggested that inequality had the greatest influence on those counties with a mortality rate of roughly 9.95 deaths per 1000 population (80th percentile) compared to any other counties. Furthermore, our results suggest that the traditional analytic methods that focus on mean or median value of the dependent variable can be, at most, applied to a narrow 20 percent of observations. This study demonstrates the value of QR. Our findings provide some insight as to why the existing evidence for the inequality-mortality relationship is mixed and suggest that analytical issues may play a role in clarifying whether inequality is a robust determinant of population health.     

Detecting spatiotemporal clusters of accidental poisoning mortality among Texas counties, U.S., 1980 – 2001

Background  

Accidental poisoning is one of the leading causes of injury in the United States, second only to motor vehicle accidents. According to the Centers for Disease Control and Prevention, the rates of accidental poisoning mortality have been increasing in the past fourteen years nationally. In Texas, mortality rates from accidental poisoning have mirrored national trends, increasing linearly from 1981 to 2001. The purpose of this study was to determine if there are spatiotemporal clusters of accidental poisoning mortality among Texas counties, and if so, whether there are variations in clustering and risk according to gender and race/ethnicity. The Spatial Scan Statistic in combination with GIS software was used to identify potential clusters between 1980 and 2001 among Texas counties, and Poisson regression was used to evaluate risk differences.     

Detecting spatiotemporal clusters of accidental poisoning mortality among Texas counties, U.S., 1980 - 2001

BACKGROUND: Accidental poisoning is one of the leading causes of injury in the United States, second only to motor vehicle accidents. According to the Centers for Disease Control and Prevention, the rates of accidental poisoning mortality have been increasing in the past fourteen years nationally. In Texas, mortality rates from accidental poisoning have mirrored national trends, increasing linearly from 1981 to 2001. The purpose of this study was to determine if there are spatiotemporal clusters of accidental poisoning mortality among Texas counties, and if so, whether there are variations in clustering and risk according to gender and race/ethnicity. The Spatial Scan Statistic in combination with GIS software was used to identify potential clusters between 1980 and 2001 among Texas counties, and Poisson regression was used to evaluate risk differences. RESULTS: Several significant (p < 0.05) accidental poisoning mortality clusters were identified in different regions of Texas. The geographic and temporal persistence of clusters was found to vary by racial group, gender, and race/gender combinations, and most of the clusters persisted into the present decade. Poisson regression revealed significant differences in risk according to race and gender. The Black population was found to be at greatest risk of accidental poisoning mortality relative to other race/ethnic groups (Relative Risk (RR) = 1.25, 95% Confidence Interval (CI) = 1.24 - 1.27), and the male population was found to be at elevated risk (RR = 2.47, 95% CI = 2.45 - 2.50) when the female population was used as a reference. CONCLUSION: The findings of the present study provide evidence for the existence of accidental poisoning mortality clusters in Texas, demonstrate the persistence of these clusters into the present decade, and show the spatiotemporal variations in risk and clustering of accidental poisoning deaths by gender and race/ethnicity. By quantifying disparities in accidental poisoning mortality by place, time and person, this study demonstrates the utility of the spatial scan statistic combined with GIS and regression methods in identifying priority areas for public health planning and resource allocation.     

The residential radon-lung cancer association in U.S. counties: a commentary

There is little doubt that underground miners exposed to radon and its progeny have increased rates of lung cancer. Residential radon exposures should carry a possibly smaller risk of increased cancer. When it became possible to collect radon data in a large number of U.S. homes and the data were aggregated by counties, the apparent association with lung cancer was a negative one, even when many other variables were taken into account. Residential radon levels are higher in suburban residences leading to a negative association with population density. Population density is strongly positively associated with lung cancer. It follows that aggregate residential radon and lung cancer rates should be negatively associated for reasons having nothing to do with the possibility of radon being carcinogenic to the lung. A second problem presented by the data is the one of sampling bias since the county lung cancer data are from the whole county population, but only a few residences are tested. Examples of other inherent associations in environmental epidemiology are cited. One strategy is to study areas of the same population density but with radon exposure gradients. This is approximated by choice of rural high radon states. Counties in such states have weak and inconsistent associations between radon and lung cancer, some of which are positive. I conclude that counties are generally inappropriate units for study of radon and lung cancer associations.     

Traumatic occupational fatalities in the U.S. and Australian construction industries

The occupational injury experience of the U.S. and Australian construction industries for 1988–1991 was compared to identify similarities and differences in risk and to share information vital for planning strategies for prevention. There were 4,158 deaths in the U.S. and 264 in the Australian construction industries. Workers in both countries, particularly laborers, were at high risk, with mean annual rates of 13.8/100,000 and 11.6, respectively, more than double the national averages. Falls, motor vehicles, electrocutions, and machinery were the leading causes of death in both countries, and accounted for 69% of the fatalities in the U.S. and 71% in Australia. International collaborations focusing injury and fatality prevention efforts on the common leading causes and high risk groups, and sharing successful prevention experiences between countries could save the lives of many construction workers world wide. © 1996 Wiley-Liss Inc.

1 This article is a US Government work and, as such, is in the public domain in the United States of America.

     

Place-of-residence errors on death certificates for two contiguous U. S. counties

Background  

Based on death certificate data, the Texas Department of Health Bureau of Vital Statistics calculates age adjusted all-cause mortality rates for each Texas county yearly. In 1998 the calculated rates for two adjacent Texas counties was disparate. These counties contain one city (Amarillo) and are identical in size. This study examined the accuracy of recorded county of residence for deaths in the two counties in 1998. In our jurisdiction, the county of residence is assigned by funeral homes.     

Formaldehyde exposure in U.S. industries from OSHA air sampling data

National occupational exposure databanks have been cited as sources of exposure data for exposure surveillance and exposure assessment for occupational epidemiology. Formaldehyde exposure data recorded in the U.S Integrated Management Information System (IMIS) between 1979 and 2001 were collected to elaborate a multi-industry retrospective picture of formaldehyde exposures and to identify exposure determinants. Due to the database design, only detected personal measurement results (n = 5228) were analyzed with linear mixed-effect models, which explained 29% of the total variance. Short-term measurement results were higher than time-weighted average (TWA) data and decreased 18% per year until 1987 (TWA data 5% per year) and 5% per year (TWA data 4% per year) after that. Exposure varied across industries with maximal estimated TWA geometric means (GM) for 2001 in the reconstituted wood products, structural wood members, and wood dimension and flooring industries (GM = 0.20 mg/m(3). Highest short-term GMs estimated for 2001 were in the funeral service and crematory and reconstituted wood products industries (GM = 0.35 mg/m(3). Exposure levels in IMIS were marginally higher during nonprogrammed inspections compared with programmed inspections. An increasing exterior temperature tended to cause a decrease in exposure levels for cold temperatures (-5% per 5 degrees C for T < 15 degrees C) but caused an increase in exposure levels for warm temperatures (+15% per 5 degrees C for T >15 degrees C). Concentrations measured during the same inspection were correlated and varied differently across industries and sample type (TWA, short term). Sensitivity analyses using TOBIT regression suggested that the average bias caused by excluding non-detects is approximately 30%, being potentially higher for short-term data if many non-detects were actually short-term measurements. Although limited by availability of relevant exposure determinants and potential selection biases in IMIS, these results provide useful insight on formaldehyde occupational exposure in the United States in the last two decades. The authors recommend that more information on exposure determinants be recorded in IMIS.     

Study rates U.S. hospitals vs. other nations, industries

American hospitals generally are further along with their total quality management programs than their Canadian counterparts but lag behind companies in other U.S. industries, according to a comprehensive international study that examined four industries--healthcare, automotive, banking and computer--in four countries--the United States, Canada, Germany and Japan.     

Cause-specific mortality in the unionized U.S. trucking industry

BACKGROUND: Occupational and population-based studies have related exposure to fine particulate air pollution, and specifically particulate matter from vehicle exhausts, to cardiovascular diseases and lung cancer. OBJECTIVES: We have established a large retrospective cohort to assess mortality in the unionized U.S. trucking industry. To provide insight into mortality patterns associated with job-specific exposures, we examined rates of cause-specific mortality compared with the general U.S. population. METHODS: We used records from four national trucking companies to identify 54,319 male employees employed in 1985. Cause-specific mortality was assessed through 2000 using the National Death Index. Expected numbers of all and cause-specific deaths were calculated stratifying by race, 10-year age group, and calendar period using U.S. national reference rates. Standardized mortality ratios (SMRs) and 95% confidence intervals (CIs) were calculated for the entire cohort and by job title. RESULTS: As expected in a working population, we found a deficit in overall and all-cancer mortality, likely due to the healthy worker effect. In contrast, compared with the general U.S. population, we observed elevated rates for lung cancer, ischemic heart disease, and transport-related accidents. Lung cancer rates were elevated among all drivers (SMR = 1.10; 95% CI, 1.02-1.19) and dockworkers (SMR = 1.10; 95% CI, 0.94-1.30); ischemic heart disease was also elevated among these groups of workers [drivers, SMR = 1.49 (95% CI, 1.40-1.59); dockworkers, SMR = 1.32 (95% CI, 1.15-1.52)], as well as among shop workers (SMR = 1.34; 95% CI, 1.05-1.72). CONCLUSIONS: In this detailed assessment of specific job categories in the U.S. trucking industry, we found an excess of mortality due to lung cancer and ischemic heart disease, particularly among drivers.     

Cancer mortality in women with probable exposure to silica: a death certificate study in 24 states of the U.S.

BACKGROUND: Silica exposure is known to cause an increased risk of pneumoconiosis and some types of cancers. Exposure to silica is becoming an increasingly common occupational hazard for women. Studies contradict each other on whether or not women suffer more occupational pneumoconiosis than men, but no studies have evaluated cancer risks among women exposed to silica. METHODS: Death certificate data on occupation and industry from 24 states in the U.S. between 1984 and 1993 were used to calculate proportional mortality ratios (PMRs) for workers exposed to silica. RESULTS: Over 20,000 deaths (4% of all deaths in persons with possible work-related silica-exposure) occurred among women. The PMR for pneumoconiosis among women working in occupations or industries with possible silica exposure was 13.6 (95% CI: 7.2-23.2), for men 3.8 (CI: 3.7-4.0). Both men and women had higher than expected PMRs for respiratory diseases, lung and esophageal cancers, and external causes of death. In the group with probable silica exposure (both occupation and industry associated with silica), women had elevated PMRs for thyroid cancer (PMR = 5.5), multiple myeloma (PMR = 1.3), digestive organ cancers (PMR = 1.2), whereas men had no increased PMRs for these cancers. Both genders had significantly decreased PMRs for breast cancer, cerebrovascular diseases, nervous system diseases, and brain and other central nervous system cancers. CONCLUSIONS: An in depth look at the types of silica exposures (specific work duties) and adjustment for confounders is warranted to determine the importance of these gender-specific excess mortalities associated with possible silica exposure.