Cancer statistics, 2001

Each year the American Cancer Society compiles estimates of the number of new cancer cases and deaths expected in the US in the current year and the most recent data on cancer incidence, mortality, and survival. An estimated 1,268,000 new cases of cancer will be diagnosed in the year 2001 and an estimated 553,400 Americans will die from cancer. Overall cancer incidence and death rates have continued to decrease in men and women since the early 1990s, and the decline in overall cancer mortality has been greater in recent years. Despite reductions in age-adjusted rates of cancer death, the total number of recorded cancer deaths in the US continues to increase, due to an aging and expanding population. Large disparities in cancer incidence and mortality across racial/ethnic groups continue. Black men and women experience higher incidence of cancer and poorer survival than white men and women. The disparity in survival reflects both diagnosis of cancer at later disease stages, and poorer survival within each stage of diagnosis.

Mortality from tobacco in developed countries: indirect estimation from national vital statistics

Prolonged cigarette smoking causes even more deaths from other diseases than from lung cancer. In developed countries, the absolute age-sex-specific lung cancer rates can be used to indicate the approximate proportions due to tobacco of deaths not only from lung cancer itself but also, indirectly, from vascular disease and from various other categories of disease. Even in the absence of direct information on smoking histories, therefore, national mortality from tobacco can be estimated approximately just from the disease mortality statistics that are available from all major developed countries for about 1985 (and for 1975 and so, by extrapolation, for 1995). The relation between the absolute excess of lung cancer and the proportional excess of other diseases can only be approximate, and so as not to overestimate the effects of tobacco it has been taken to be only half that suggested by a recent large prospective study of smoking and death among one million Americans. Application of such methods indicates that, in developed countries alone, annual deaths from smoking number about 0.9 million in 1965, 1.3 million in 1975, 1.7 million in 1985, and 2.1 million in 1995 (and hence about 21 million in the decade 1990-99: 5-6 million European Community, 5-6 million USA, 5 million former USSR, 3 million Eastern and other Europe, and 2 million elsewhere, [ie, Australia, Canada, Japan, and New Zealand]). More than half these deaths will be at 35-69 years of age: during the 1990s tobacco will in developed countries cause about 30% of all deaths at 35-69 (making it the largest single cause of premature death) plus about 14% of all at older ages. Those killed at older ages are on average already almost 80 years old, however, and might have died soon anyway, but those killed by tobacco at 35-69 lose an average of about 23 years of life. At present just under 20% of all deaths in developed countries are attributed to tobacco, but this percentage is still rising, suggesting that on current smoking patterns just over 20% of those now living in developed countries will eventually be killed by tobacco (ie, about a quarter of a billion, out of a current total population of just under one and a quarter billion).

Intentional weight loss and mortality among overweight individuals with diabetes

OBJECTIVE

To estimate the effect of intentional weight loss on mortality in overweight individuals with diabetes.

RESEARCH DESIGN AND METHODS

We performed a prospective analysis with a 12-year mortality follow-up (1959-1972) of 4,970 overweight individuals with diabetes, 40-64 years of age, who were enrolled in the American Cancer Society's Cancer Prevention Study I. Rate ratios (RRs) were calculated, comparing overall death rates, and death from cardiovascular disease (CVD) or diabetes in individuals with and without reported intentional weight loss.

RESULTS

Intentional weight loss was reported by 34% of the cohort. After adjustment for initial BMI, sociodemographic factors, health status, and physical activity, intentional weight loss was associated with a 25% reduction in total mortality (RR = 0.75; 95% CI 0.67-0.84), and a 28% reduction in CVD and diabetes mortality (RR = 0.72; 0.63-0.82). Intentional weight loss of 20-29 lb was associated with the largest reductions in mortality (approximately 33%). Weight loss >70 lb was associated with small increases in mortality

CONCLUSIONS

Intentional weight loss was associated with substantial reductions in mortality in this observational study of overweight individuals with diabetes.

Prospective study of intentional weight loss and mortality in never-smoking overweight US white women aged 40-64 years

Although 40% of US women indicate they are currently trying to lose weight, the association between intentional weight loss and longevity is unknown. The authors analyzed prospective data from 43,457 overweight, never-smoking US white women aged 40-64 years who in 1959-1960 completed a questionnaire that included questions on weight change direction, amount, time interval, and intentionality. Vital status was determined in 1972. Proportional hazards regression was used to estimate mortality rate ratios for women who intentionally lost weight compared with women who had no change in weight. Women who died within the first 3 years of follow-up were excluded. Analyses were stratified by preexisting illness and adjusted for age, beginning body mass index, alcohol intake, education, physical activity, and health conditions. In women with obesity-related health conditions (n = 15,069), intentional weight loss of any amount was associated with a 20% reduction in all-cause mortality, primarily due to a 40-50% reduction in mortality from obesity-related cancers; diabetes-associated mortality was also reduced by 30-40% in those who intentionally lost weight. In women with no preexisting illness (n = 28,388), intentional weight loss of > or = 20 lb (> or = 9.1 kg) that occurred within the previous year was associated with about a 25% reduction in all-cause, cardiovascular, and cancer mortality; however, loss of < 20 lb (< 9.1 kg) or loss that occurred over an interval of > or = 1 year was generally associated with small to modest increases in mortality. The association between intentional weight loss and longevity in middle-aged overweight women appears to depend on their health status. Intentional weight loss among women with obesity-related conditions is generally associated with decreased premature mortality, whereas among women with no preexisting illness, the association is equivocal.

Mortality from smoking worldwide

Estimates are made of the numbers and proportions of deaths attributable to smoking in 44 developed countries in 1990. In developed countries as a whole, tobacco was responsible for 24% of all male deaths and 7% of all female deaths, rising to over 40% in men in some former socialist economies and 17% in women in the USA. The average loss of life for all cigarette smokers was about 8 years and for those whose deaths were attributable to tobacco about 16 years. Trends in mortality attributable to tobacco differed between countries. In some the mortality in middle age (35-69 years) had decreased by half in men since 1965; in others it was continuing to increase. In women, the proportion was mostly increasing, almost universally in old age. Mortality not attributable to smoking decreased since 1955 in all OECD (Organization for European Collaboration and Development) countries, by up to 60% in men and more in women. No precise estimate can be made of the number of deaths attributable to smoking in undeveloped countries, but the prevalence of smoking suggests that it will be large. In the world as a whole, some 3 million deaths a year are estimated to be attributable to smoking, rising to 10 million a year in 30-40 years' time.

Relation between geographic variability in kidney stones prevalence and risk factors for stones

To determine whether geographic variability in rates of kidney stones in the United States was attributable to differences in personal and environmental exposures, the authors examined cross-sectional data that included information on self-reported, physician-diagnosed kidney stones collected from 1,167,009 men and women, aged > or = 30 years, recruited nationally in 1982. Information on risk factors for stones including age, race, education, body mass, hypertension, and diuretic and vitamin C supplement use was obtained by self administered questionnaire. Consumption of milk, coffee, tea, soft drinks, and alcohol was based on food frequency data. Indices of ambient temperature and sunlight level were assigned to subjects based on state of residence. Stones were nearly twice as prevalent in the Southeast as in the Northwest among men and women. Ambient temperature and sunlight indices were independently associated with stones prevalence after controlling for other risk factors for stones. Regional variation was eliminated for men and greatly reduced for women after adjustment for temperature, sunlight, and beverage consumption. Other factors appeared to not contribute to regional variation. These results provide evidence that ambient temperature and sunlight levels are important risk factors for stones and that differences in exposure to temperature and sunlight and beverages may contribute to geographic variability.

Prospective study of intentional weight loss and mortality in overweight white men aged 40-64 years

Although 25% of US men indicate that they are trying to lose weight, the association between intentional weight loss and longevity in men is unknown. The authors analyzed prospective data from 49,337 overweight (initial body mass index > or =27) white men aged 40-64 years who, in 1959-1960, answered questions on weight change direction, amount, time interval, and intent. Vital status was determined in 1972. Proportional hazards regression estimated mortality rate ratios for men who intentionally lost weight compared with men with no weight change. Analyses were stratified by health status and adjusted for age, initial body mass index, smoking status, alcohol intake, education, physical activity, health history, and physical symptoms. Among men with no reported health conditions (n = 36,280), intentional weight loss was not associated with total, cardiovascular (CVD), or cancer mortality, but diabetes-associated mortality was increased 48% (95% confidence interval (CI) -7% to +133%) among those who lost 20 pounds (9.1 kg) or more; this increase was largely related to non-CVD mortality. Among men with reported health conditions (n = 13,057), intentional weight loss had no association with total or CVD mortality, but cancer mortality increased 25% (95% confidence interval -4% to +63%) among those who lost 20 pounds or more. Diabetes-associated mortality was reduced 32% (95% confidence interval -52% to -5%) among those who lost less than 20 pounds and 36% (95% confidence interval -49% to -20%) among those who lost more than 20 pounds. These results and those from our earlier study in women (Williamson et al., Am J Epidemiol 1995;141:1128-41) suggest that intentional weight loss may reduce the risk of dying from diabetes, but not from CVD. In observational studies, however, it is difficult to separate intentional weight loss from unintentional weight loss due to undiagnosed, underlying disease. Well-designed observational studies, as well as randomized controlled trials, are needed to determine whether intentional weight loss reduces CVD mortality.

Environmental tobacco smoke and coronary heart disease in the American Cancer Society CPS-II cohort

BACKGROUND

Thirteen of 14 epidemiological studies have shown an increased risk of approximately 20% for coronary heart disease (CHD) for never-smokers exposed to environmental tobacco smoke (ETS), but this association remains controversial. If true, ETS might account for an estimated 35,000 to 40,000 heart disease deaths per year in the United States.

METHODS AND RESULTS

We have conducted the largest study to date, a prospective study of 353,180 female and 126,500 male never-smokers enrolled in 1982 in the American Cancer Society's Cancer Prevention Study II and followed through 1989. Analyses focused on subcohorts of 309,599 married pairs and of 135,237 subjects concordant for self-reported exposure and exposure reported by each one's spouse. More than 2800 CHD deaths (ICD 410-414) occurred among married pairs; 10% of married men and 28% of married women were married to currently smoking spouses, while 10% and 32%, respectively, were married to former smokers. After controlling for many cardiovascular risk factors, we found 22% higher CHD mortality (rate ratio, 1.22; 95% CI, 1.07 to 1.40) among never-smoking men married to currently smoking wives compared with those married to wives who had never smoked. The corresponding rate ratio for women was 1.10 (0.96 to 1.27). Never-smokers living with former smokers showed no increased risk. When analyses were restricted to subjects whose ETS exposure was classified via both their own self-report and a spouse's report, the rate ratio was 1.23 (1.03 to 1.47) for currently exposed men and 1.19 (0.97 to 1.45) for women.

CONCLUSIONS

Results are consistent with prior reports that never-smokers currently exposed to ETS have about 20% higher CHD death rates. However, our data do not show consistent dose-response trends and are possibly subject to confounding by unmeasured risk factors.

A dose-response analysis and quantitative assessment of lung cancer risk and occupational cadmium exposure

We performed a quantitative assessment of the risk of lung cancer from exposure to cadmium based on a retrospective cohort mortality study of cadmium-exposed workers. The study population consisted of white male workers who were employed for at least 6 months at a cadmium smelter between January 1, 1940, and December 31, 1969, and who were first employed at the facility on or after January 1, 1926. The study findings were analyzed using a modified life-table analysis to estimate standardized mortality ratios (SMRs), and various functional forms (i.e., exponential, power, additive relative rate, and linear) of Poisson and Cox proportional hazards models to examine the dose-response relationship. Estimates of working lifetime risk (45 years) were developed using an approach that corrects for competing causes of death. An excess in mortality from lung cancer was observed for the entire cohort (SMR = 149, 95% confidence interval (CI) = 95, 222). Mortality from lung cancer was greatest among non-Hispanic workers (SMR = 211, 95% CI = 131, 323), among workers in the highest cadmium exposure group (SMR = 272, 95% CI = 123, 513), and among workers with 20 or more years since the first exposure (SMR = 161, 95% CI = 100, 248). A statistically significant dose-response relationship was evident in nearly all of the regression models evaluated. Based on our analyses, the lifetime excess lung cancer risk at the current Occupational Safety and Health Administration standard for cadmium fumes of 100 micrograms/m3 is approximately 50 to 111 lung cancer deaths per 1000 workers exposed to cadmium for 45 years.

Parity and coronary heart disease among women in the American Cancer Society CPS II population

Four of five cohort studies have shown an increase in cardio-vascular disease with increased parity, after control for a number of cardiovascular risk factors. The effect has been observed primarily in categories of four or more livebirths. To analyze this issue further, we conducted an analysis of 585,445 women from the American Cancer Society Cancer Prevention Survey II (CPS II). There were 4,787 deaths from coronary heart disease (International Classification of Diseases Codes 410-414) among these women during the follow-up period from 1981 to 1989. After controlling for a number of cardiovascular risk factors, we found no increased trend in heart disease with increased parity. Rare ratios for women with no live births or 1, 2, 3, 4, 5, and 6 or more livebirths were 1.00, 0.95, 0.89, 0.82, 0.94, 0.98, 0.94, respectively. Without control over confounders, however, we observed an increased risk for the highest party category (rate ratio = 1.18; 95% confidence interval = 1.04-1.34). Positive findings for parity to date have been found primarily in cohort studies representative of the general population, whereas our own data and another earlier negative study among nurses came from more select populations likely to be relatively homogeneous for socioeconomic variables. Positive findings in the literature may be due, at least in part, to confounding by unmeasured variables related to socioeconomic status.

Epidemiologic studies of fatal and nonfatal cardiovascular disease and ETS exposure from spousal smoking

This article reviews the epidemiologic studies of the association of ischemic heart disease risk and environmental tobacco smoke (ETS) exposure from a spouse who smokes. Seventeen studies (nine cohort, eight case-control) comprising more than 485,000 lifelong nonsmokers and 7,345 coronary heart disease (CHD) events were included in a meta-analysis. Together, these studies include 36% more CHD events and 58% more study subjects than were available for review by the U. S. Occupational Safety and Health Administration (OSHA) in 1994. The relative risk (RR) for fatal or nonfatal coronary events among never smokers married to smokers, compared to those whose spouses did not smoke, was RR = 1.25 (95% confidence interval [95% CI], 1.17-1.33) across the combined studies. This association was statistically similar in men (RR = 1.24; 95% CI, 1.15-1.32) and women (RR = 1.23; 95% CI, 1.15-1.32); in studies of cohort (RR = 1.23; 95% CI, 1.15-1. 31) and case-control (RR = 1.47; 95% CI, 1.19-1.81) design; in the United States (RR =1.22; 95% CI, 1.13-1.30) and other countries (RR = 1.41; 95% CI, 1.21-1.65); and in studies of fatal (RR = 1.22; 95% CI, 1.14-1.30) and nonfatal (RR = 1.32; 95% CI, 1.04-1.67) heart disease. In three studies that presented data separately for nonsmokers married to current or former smokers, the association was stronger when the spouses continued to smoke (RR = 1.16, 1.06-1.28) than with former smokers (RR = 0.98; 95% CI, 0.89-1.08). The aggregate data are unlikely to be attributable to chance, publication bias, confounding, or misclassification of exposure. The evidence linking heart disease and ETS exposure from a spouse has become substantially stronger since OSHA first proposed including heart disease in its risk assessment of ETS in 1994.

Bladder tumors in two young males occupationally exposed to MBOCA

MBOCA (4,4' methylenebis (2-chloroaniline) is a structural analogue of benzidine and is carcinogenic in mice, rats, and dogs. MBOCA has not yet been demonstrated to be carcinogenic in humans and is not regulated as an occupational carcinogen in the United States. We report two noninvasive papillary tumors of the bladder identified in a screening study of 540 workers exposed to MBOCA during its production at a Michigan chemical plant from 1968 to 1979. Both tumors occurred in men under 30 years old who had never smoked. Although the prevalence of grade 1-2 tumors among asymptomatic males in this age group is unknown, the incidence of clinically apparent tumors on U.S. males aged 25-29 is only 1 per 100,000 per year. The detection of the two tumors in young, nonsmoking males is consistent with the hypothesis that MBOCA induces bladder neoplasms in humans.

Screening workers exposed to 4,4'-methylenebis(2-chloroaniline) for bladder cancer by cystoscopy

A bladder cancer incidence study was conducted among 540 workers exposed to the potential bladder carcinogen 4,4'-methylenebis(2-chloroaniline) from 1969 to 1979. Among the 385 workers who participated in a urine screening examination, none had suspicious or positive cytology. Twenty-one workers had at least one reading of atypia and 60 had either a positive dipstick for heme or greater than five red blood cells per low power field. The study protocol initially involved referral to private physicians for follow-up of any suspicious laboratory results. However, the diagnosis by cystoscopy of a bladder tumor in a nonsmoking man less than 30 years old with low-level hematuria prompted us to offer cystoscopy to all members of the cohort. A total of three tumors were identified in 200 persons who received cystoscopy. All were low-grade, papillary tumors and two occurred in men with completely normal urine screening results. These findings suggest that cystoscopy of asymptomatic persons should be considered in designing bladder cancer screening programs in high-risk cohorts.

Surveillance of occupational skin disease using the Supplementary Data System

The utility of the Supplementary Data System (SDS) compiled by the Bureau of Labor Statistics (BLS) in conducting surveillance of occupational skin disease was evaluated by examining 14,703 workers' compensation cases reported to the SDS for the year 1981. Combined with state employment denominators obtained from the BLS Employment and Earnings Program, rates of illness (cases of dermatitis/10,000 employed) calculated for eight major industrial divisions varied significantly according to the criteria used for reporting cases. Despite quantitative variations in the rate of skin disease that depended on specific reporting criteria, the relative ranking of the major industrial divisions remained unchanged, with highest rates of skin disease consistently found in three major industry divisions: agriculture, manufacturing, and construction. This ranking of major industry divisions by rate of dermatitis corresponded extremely well with rankings generated from the 1981 Annual Survey (Spearman rank correlation = .98, p less than .01). At the two-digit level of the Standard Industrial Classification, the rankings based on the SDS had a 77% rank correlation with those from the Annual Survey. Two-digit SIC codes identified from the top 10 in both sets of rankings included crop and livestock production from the agricultural division and leather products, food products, rubber and plastic products from the manufacturing division.

Lung cancer mortality rates in birth cohorts in the United States from 1960 to 1994

We sought to describe the changing death rates from lung cancer in the US white population in sequential birth cohorts, adjusting for cohort smoking prevalence and duration. We searched the US mortality database (1960-1994) for all deaths among whites in which lung cancer was listed as the underlying cause of death. To determine the population at risk for lung cancer, we used the 1970, 1978-1980, and 1992 National Health Interview Surveys to estimate the annual number of current and recent smokers (those who had quit within 5 years) in 11 5-year birth cohorts, starting in 1901. We then determined annual lung cancer mortality rates for each birth cohort, stratified by sex and adjusting for the prevalence and duration of smoking. The population-based rates of lung cancer mortality were much higher among men than among women across all ages and birth cohorts, reflecting higher smoking rates among men. These differences decreased after we controlled for current and recent smoking within the cohorts and were slightly increased in women after we controlled for duration of smoking. Differences in lung cancer death rates across birth cohorts of US men and women primarily reflect differences in the prevalence and duration of smoking in these birth cohorts. Changes in cigarette design that have greatly reduced tar yields have a relatively small effect compared with that of people's smoking status and duration of smoking.

Lung cancer deaths in the United States from 1979 to 1992: an analysis using multiple-cause mortality data

BACKGROUND

We sought to describe trends in the presence of lung cancer at the time of death in the United States from 1979 to 1992.

METHODS

We analysed death certificate reports in the Multiple-Cause Mortality Files compiled by the National Center for Health Statistics, searching for any mention of lung cancer, lung cancer as the underlying cause of death, and comorbid conditions.

RESULTS

Of the 29,042,213 decedents in the study period, 1,892,129 (6.5%) had a diagnosis of lung cancer listed on their death certificates; of these 1,892,129 decedents, 1,734,767 (91.7%) had lung cancer listed as the underlying cause of death. Decedents with lung cancer listed as being present but not the underlying cause of death were more likely to be male (relative risk [RR] 1.16, 95% confidence interval [CI]: 1.15-1.17), and older (RR 4.61, 95% CI: 4.35-4.88 for decedents older than 85 compared to those aged less than 44), but less likely to be black than white (RR 0.88, 95% CI: 0.87-0.90). The mortality rate, age-adjusted to the 1980 population, increased 23.0%, from 47.9 per 100,000 in 1979 to 58.9 per 100,000 in 1992. Over the study period, black men had the highest mortality rates (117.3-125.2 per 100,000), followed by white men (81.7-88.7 per 100,000), men of other races (37.4-46.7 per 100,000), white women (22.1-39.1 per 100,000), black women (21.4-38.2 per 100,000), and women of other races (12.6-18.1 per 100,000). Age-adjusted, state specific rates varied threefold, from 30.4 per 100,000 in Utah to 93.9 per 100,000 in Nevada.

CONCLUSIONS

We conclude that the underlying cause of death data base, which captures almost 92% of decedents with lung cancer present, accurately tracks lung cancer mortality trends in the US. Mortality rates of lung cancer, which are decreasing among men, continue to increase among women.

Case studies in international tobacco surveillance: cigarette smuggling in Brazil

OBJECTIVE

This article is the first in a series of international case studies developed by the American Cancer Society to illustrate use of publicly available surveillance data for regional tobacco control.

DESIGN

A descriptive analysis of Brazil and Paraguay cigarette production and trade data from official sources.

METHODS

Per capita cigarette consumption for Brazil and its neighbour was calculated from 1970 to 1998 using data on production, imports, and exports from NATIONS, the National Tobacco Information Online System.

RESULTS

A 63% decrease was observed in the estimate of per capita consumption of cigarettes in Brazil between 1986 and 1998 (from 1913 cigarettes per person in 1986 to 714 cigarettes per person in 1998) and a 16-fold increase in Paraguay was observed during the same period (from 678 cigarettes per person in 1986 to 10 929 cigarettes per person in 1998). Following Brazil's 1999 passage of a 150% cigarette export tax, cigarette exports fell 89% and Brazil's estimated per capita consumption rose to 1990 levels (based on preliminary data). Per capita consumption in Paraguay also fell to 1990 levels.

CONCLUSIONS

These trends coincide with local evidence that large volumes of cigarettes manufactured in Brazil for export to Paraguay are smuggled back and consumed as tax-free contraband in Brazil. It is hoped that this case study will draw wider public attention to the problems that smuggling presents for tobacco control, help identify other countries confronting similar issues, and stimulate effective interventions.

Morbidity from repetitive knee trauma in carpet and floor layers

Carpet layers comprise less than 0.06% of the United States workforce yet they submit 6.2% of compensation claims for traumatic knee inflammation. Their work involves multiple sources of acute and chronic knee trauma including kneeling, pressure from sharp objects, and use of a device called a "knee kicker" to stretch wall to wall carpet. To characterise the knee morbidity in carpet layers and to identify occupational risk factors, a questionnaire was completed by 112 carpet and floor layers, 42 tile and terrazo setters, and 243 millwrights and bricklayers (MWBL). The MWBL comparison workers seldom kneel and do not use a knee kicker. Physical and xray examinations were conducted on a subset of 108 respondents to validate the questionnaire responses. Compared with the MWBL, carpet layers reported more frequent bursitis (20% v 6%), needle aspiration of knee fluid (32% v 6%), and skin infections of the knee (7% v 2%). A score indicating frequency of using the knee kicker was the only statistically significant predictor of bursitis, whereas the score for kneeling was one of several predictors of knee aspiration and skin infections of the knee. These data suggest that carpet and floor layers experience substantially more knee morbidity than other occupational groups, and that kneeling and use of the knee kicker are risk factors providing opportunities for prevention.

Cardiovascular mortality among munitions workers exposed to nitroglycerin and dinitrotoluene

A retrospective cohort mortality study with 5529 nitroglycerin, 4989 dinitrotoluene, and 5136 unexposed workers compared the mortality of the exposed groups with that of the United States population and that of the unexposed group with life-table analysis and Poisson regression. Mortality from ischemic heart disease was close to that expected, and mortality from cerebrovascular disease was slightly less than that expected, for the workers with both nitroglycerin and dinitrotoluene exposure and for those with dinitrotoluene exposure only. A significant interaction between age and nitroglycerin exposure was detected in the Poisson regression analyses for ischemic heart disease, particularly for workers actively exposed to nitroglycerin. The rate ratio for the workers under 45 years of age and actively exposed to nitroglycerin was 3.30 (95% confidence interval 129-8.48). This study did not show a chronic effect of nitroglycerin or dinitrotoluene exposure on cardiovascular disease risk. Potential biases related to the company's medical screening program may have limited the ability to detect chronic cardiovascular effects.

Reducing knee morbidity among carpetlayers

Carpetlayers have a high prevalence of occupational knee morbidity, partly attributable to their use of the knee kicker to stretch carpet for wall-to-wall installation. While a mechanical alternative "power stretcher" is available, knee kickers are still widely used. A questionnaire survey indicated that unavailability of the mechanical stretcher at installation sites was a major factor for continued use of the knee kicker. Strategies to reduce use of the knee kicker are discussed.

The estimated predictive value of screening for illicit drugs in the workplace

This paper estimates the predictive values of screening tests for six illicit drugs of common concern in the workplace (amphetamines, barbiturates, cocaine, hallucinogens, marijuana, and opiates) using published information on test sensitivity and specificity and survey data on prevalence. Estimated predictive values (negative) were generally high, whereas the estimated predictive value of a positive test ranged from 1 per cent for amphetamines to 100 per cent for hallucinogens and was only 38 per cent for marijuana, the most prevalent drug.

Fatal chemical pneumonia from 1,1,2,3,3-pentafluoro-3-chloropropene in an unmarked gas tank

Fatal chemical pneumonia occurred in a worker following exposure to an unidentified gas in a salvaged cylinder. Inspection of the tank revealed a scrawled chemical formula for 1,1,2,3,3-pentafluoro-3-chloropropene, a suspected pulmonary irritant. The report underscores the potential hazards which salvaged cylinders pose to individuals who use or refill them. The population at risk includes scuba divers, emergency rescue personnel, and workers in the compressed gas industry.