Martha A Waters | University of California, Berkeley (original) (raw)
Papers by Martha A Waters
The National Institute for Occupational Safety and Health evaluated farm pesticide exposure and g... more The National Institute for Occupational Safety and Health evaluated farm pesticide exposure and glioma risk in a study that included 457 glioma cases and 648 population-based controls, all adult men (18-80 yr old) and nonmetropolitan residents of Iowa, Michigan, Minnesota, and Wisconsin. Multiple logistic regressions were used to control for farm residence, age, age group, education, and exposure to other pesticides. No associations were found between glioma and 12 specific pesticides. We estimated adjusted odds ratios (ORs) and 95% confidence intervals (CIS) and found reduced glioma risk for insecticides (OR = 0.53, CI = 0.37-0.77), fumigants (OR = 0.57, CI = 0.34-0.951, and organochlorines (OR = 0.66, CI = 0.47-0.94). in analyses excluding proxy respondents (47% of cases) most CIs included 1.O. No positive association of farm pesticide exposure and glioma was found. Other farm exposures may explain the excess brain cancer risk seen in previous studies.
The National Institute for Occupational Safety and Health evaluated farm pesticide exposure and g... more The National Institute for Occupational Safety and Health evaluated farm pesticide exposure and glioma risk in a study that included 457 glioma cases and 648 population-based controls, all adult men (18-80 yr old) and nonmetropolitan residents of Iowa, Michigan, Minnesota, and Wisconsin. Multiple logistic regressions were used to control for farm residence, age, age group, education, and exposure to other pesticides. No associations were found between glioma and 12 specific pesticides. We estimated adjusted odds ratios (ORs) and 95% confidence intervals (CIS) and found reduced glioma risk for insecticides (OR = 0.53, CI = 0.37-0.77), fumigants (OR = 0.57, CI = 0.34-0.951, and organochlorines (OR = 0.66, Ci = 0.47-0.94). in analyses excluding proxy respondents (47% of cases) most Cis included 1 .O. No positive association of farm pesticide exposure and glioma was found. Other farm exposures may explain the excess brain cancer risk seen in previous studies.
Objective: Glioma is the most common primary malignant brain tumor in adults, responsible for 75%... more Objective: Glioma is the most common primary malignant brain tumor in adults, responsible for 75% of adult primary malignant brain tumors, yet aside from its association with ionizing radiation, its etiology is poorly understood. Sex differences in brain tumor incidence suggest that hormonal factors may play a role in the etiology of these tumors, but few studies have examined this association in detail. The objective of this study was to explore the role of reproductive factors in the etiology of glioma in women. Method: As part of a population-based case-control study, histolog-ically confirmed primary glioma cases (n = 341 women) diagnosed between January 1, 1995 and January 31, 1997 were identified through clinics and hospitals in four Midwest U.S. states. Controls (n = 527 women) were randomly selected from lists of licensed drivers and Health Care Finance Administration enrollees. In-person interviews with subjects (81%) or their proxies (19%) collected reproductive history and other exposure information. Results: Glioma risk increased with older age at men-arche (P for trend = 0.009) but only among postmeno-pausal women. Compared with women who never breast-fed, women who breast-fed >18 months over their lifetime were at increased risk of glioma (odds ratio, 1.8; 95% confidence interval, 1.1-2.9). Women who reported using hormones for symptoms of menopause had a decreased risk of glioma compared with women who never used such hormones (odds ratio, 0.7; 95% confidence interval, 0.5-1.1). Conclusion: These results support the hypothesis that reproductive hormones play a role in the etiology of glioma among women. (Cancer Epidemiol Biomarkers Prev 2004;13(10):1583 – 8)
The commercial aircraft cabin is an often-overlooked indoor environment occupied by both flight c... more The commercial aircraft cabin is an often-overlooked indoor environment occupied by both flight crew and the general public. Endotoxin exposure in indoor environments has been linked to a variety of health conditions. In this study, endotoxin was readily detected in the air and dust of commercial aircraft during passenger flights, and mean air and dust endotoxin levels in the aircraft cabins were generally higher, and more potent, than those reported for homes and offices. Endotoxin levels also varied significantly by dust source (carpet or seat). Density of occupancy, duration of occupancy, and hygienic conditions may partly explain differences across studies.
Exposures to cabin environmental contaminants were measured on 36 commercial transport aircraft. ... more Exposures to cabin environmental contaminants were measured on 36 commercial transport aircraft. The objectives were to characterize levels of contaminants and evaluate the relationship between flight factors such as aircraft size, occupancy, ventilation, and flight length, and environmental parameters. Monitoring was conducted at two coach locations for the duration of the flight for VOCs,
Background NIOSH is conducting health studies of female ¯ight attendants. Exposures of interest i... more Background NIOSH is conducting health studies of female ¯ight attendants. Exposures of interest include cosmic radiation and circadian rhythm disruption, however, the data needed to estimate cumulative radiation dose are not found in work histories. Methods We developed an algorithm to generate from work histories the required input data for Federal Aviation Administration radiation estimation software and evaluated whether effects of cumulative radiation dose could be distinguished analytically from effects of circadian rhythm disruption. Results The algorithm has relatively low bias (` 6%) for longer ¯ights, which contribute most to cumulative radiation dose. In one NIOSH study, 44 crew incurred an estimated average annual occupational dose of 1.5±1.7 mSv. Selection of a study population ¯ying predominantly North±South ¯ights can provide the necessary distinction between radiation and time zone crossing exposures. Conclusions Methods developed will be useful for exposure assessment in cabin crew studies with relatively short study periods, (e.g., reproductive health studies) for which limited ¯ight history details are generally available. Am. J. Ind. Med. 41:27±37, 2002.
—Air crew are exposed to elevated levels of cosmic ionizing radiation of galactic and solar origi... more —Air crew are exposed to elevated levels of cosmic ionizing radiation of galactic and solar origin and are among the more highly exposed occupational groups to ionizing radiation in the United States. Depending on flight route patterns, the annual dose may range from 0.2 to 5 mSv. By comparison, the average annual radiation dose equivalent of occupationally exposed adults in the United States is estimated to be 1.1 mSv. Cosmic-radiation dose depends primarily on altitude and geomagnetic latitude and to a lesser degree on solar activity. Although the International Commission on Radiological Protection has recommended that air crew exposures to natural radiation in-flight be treated as occupational exposures, United States flight crew exposures to natural cosmic radiation are not regulated or typically monitored. There are approximately 148,000 air crew (flight deck crew and flight attendants) in the United States. Health Phys. 79(5):553–559; 2000
The lognormal distribution is often applied to occupational exposures, yet the assumption of logn... more The lognormal distribution is often applied to occupational exposures, yet the assumption of lognormality is rarely verified. This lack of rigor in evaluating the appropriateness of the lognormal model has resulted, in part, from the difficulty of applying formal goodness-of-fit tests. When evaluation of model fit has been attempted, occupational hygienists have relied upon probability plotting of exposures rather than upon formal statistical methods. The goal of this work was to develop for the occupational hygienist a simple quantitative evaluation to supplement the probability plot. A measure of goodness-of-fit to the lognormal model based on the ratio of two estimators of the mean of the distribution, the simple or direct estimate of the mean and the maximum likelihood estimate of the mean of a lognormal distribution, is described. This new measure, the ratio metric, is a simple extension of calculations made routinely by many occupational hygienists. Results from using the ratio metric were compared to probability plotting and to two traditional measures of goodness-of-fit, the Lilliefors test and the W test,for two occupational exposure data sets. The results of the ratio and W tests are comparable for a variety of occupational exposure data, but the Lilliefors test is overly conservative and does not detect several cases of gross deviations from lognormality. The ratio metric is an effective alternative to the Lilliefors test and is easier to perform than the W test for the range of data usually encountered by occupational hygienists. Occupational hygienists are encouraged to use the ratio metric in conjunction with the probability plot in evaluating the lognormal assumption.
Air concentrations were obtained for 55 individual chemical components of gasoline measured by ei... more Air concentrations were obtained for 55 individual chemical components of gasoline measured by eight petroleum companies for service station attendants (n = 491, transport drivers (n = 49), and outside operators (n = 56) during the summer of 1984. Approximate 95 percent confidence intervals were computed for the mean exposures to each of the 55 components in the three job groups. Exposures of service station attendants were significantly lower when vapor recovery systems were present; exposures in the other two job groups were apparently unaffected by vapor recovery systems. The ratios of air concentrations of the 16 most abundant vapor components to the air concentrations of total hydrocarbons (THC) comprised 80-84 percent. It was observed that the vapor ratios calculated in this investigation were similar to those of the same 16 components reported in a previous investigation by McDermott and Killiany in 1978. This apparent stability of vapor ratios suggests the possibility that exposures of individual gasoline components might be estimated solely on the basis of THC measurements. This hypothesis was tested by comparing predicted air levels for 23 hydrocarbons with those actually observed in a recent investigation by Tironi et a/ (1986) and relatively good agreement was observed. Rappaport, S. M.; Selvin, S.; Waters, M. A.: Exposures to hydrocarbon components of gasoline in the petroleum industry. Appl. lnd. Hyg. 2:148-154; 1987.
Journal of occupational and environmental hygiene, Jan 24, 2015
The fundamental goal of this paper is to describe, define and analyze the components of the risk ... more The fundamental goal of this paper is to describe, define and analyze the components of the risk characterization process for occupational exposures. Current methods are described for the probabilistic characterization of exposure, including newer techniques that have increasing applications for assessing data from occupational exposure scenarios. In addition, since the probability of health effects reflects variability in the exposure estimate as well as the dose-response curve - the integrated considerations of variability surrounding both components of the risk characterization provide greater information to the occupational hygienist. Probabilistic tools provide a more informed view of exposure as compared to use of discrete point estimates for these inputs to the risk characterization process. Active use of such tools for exposure and risk assessment will lead to a scientifically supported worker health protection program. Understanding the bases for an occupational risk assess...
Epidemiology, 2006
Production of polychlorinated biphenyls (PCBs) ended in the United States in the 1970s, but PCBs ... more Production of polychlorinated biphenyls (PCBs) ended in the United States in the 1970s, but PCBs persist in the environment and are detectable in the blood of approximately 80% of Americans over age 50. PCBs decrease dopamine levels in rats and monkeys. Loss of dopamine is the hallmark of Parkinson disease, a neurodegenerative disease. There are no epidemiologic studies of PCBs and neurodegenerative disease. We conducted a retrospective mortality study of 17,321 PCB-exposed workers to determine whether mortality from Parkinson disease, dementia, and amyotrophic lateral sclerosis was elevated compared with the U.S. population. All workers had a least 90 days employment in 1 of 3 electrical capacitor plants using PCBs from the 1940s to the 1970s. PCB serum levels from a sample of these workers in the 1970s were approximately 10 times the level of community controls. We found no overall excess of Parkinson disease, amyotrophic lateral sclerosis, or dementia in the PCB-exposed cohort (standardized mortality ratios [SMRs]-1.40, 1.11, and 1.26, respectively, and number of deaths-14, 10, and 28 respectively). However, sex-specific analyses revealed that women had an excess of amyotrophic lateral sclerosis (SMR-2.26; 95% confidence interval [CI] = 1.08-4.15; 10 deaths). Furthermore, among highly exposed women (defined by a job-exposure matrix), we found an excess of Parkinson disease (SMR-2.95; 95% CI = 1.08-6.42; 6 deaths) and dementia (SMR-2.04; 95% CI = 1.12-3.43; 14 deaths). Our data are limited due to small numbers and reliance on mortality rather than incidence data, but are suggestive of an effect of PCBs on neurodegenerative disease for women. The literature does not offer an explanation for why women would be more affected than men by PCB exposure for these outcomes.
AIHce 1997 - Taking Responsibility...Building Tomorrow's Profession Papers, 1997
The objective of this analysis was to evaluate mortality among a cohort of 24,865 capacitor-manuf... more The objective of this analysis was to evaluate mortality among a cohort of 24,865 capacitor-manufacturing workers exposed to polychlorinated biphenyls (PCBs) at plants in Indiana, Massachusetts, and New York and followed for mortality through 2008. Cumulative PCB exposure was estimated using plant-specific job-exposure matrices. External comparisons to US and state-specific populations used standardized mortality ratios, adjusted for gender, race, age and calendar year. Among long-term workers employed 3 months or longer, within-cohort comparisons used standardized rate ratios and multivariable Poisson regression modeling. Through 2008, more than one million person-years at risk and 8749 deaths were accrued. Among long-term employees, all-cause and all-cancer mortality were not elevated; of the a priori outcomes assessed only melanoma mortality was elevated. Mortality was elevated for some outcomes of a priori interest among subgroups of long-term workers: all cancer, intestinal cancer and amyotrophic lateral sclerosis (women); melanoma (men); melanoma and brain and nervous system cancer (Indiana plant); and melanoma and multiple myeloma (New York plant). Standardized rates of stomach and uterine cancer and multiple myeloma mortality increased with estimated cumulative PCB exposure. Poisson regression modeling showed significant associations with estimated cumulative PCB exposure for prostate and stomach cancer mortality. For other outcomes of a priori interest--rectal, liver, ovarian, breast, and thyroid cancer, non-Hodgkin lymphoma, Alzheimer disease, and Parkinson disease--neither elevated mortality nor positive associations with PCB exposure were observed. Associations between estimated cumulative PCB exposure and stomach, uterine, and prostate cancer and myeloma mortality confirmed our previous positive findings.
The National Institute for Occupational Safety and Health evaluated farm pesticide exposure and g... more The National Institute for Occupational Safety and Health evaluated farm pesticide exposure and glioma risk in a study that included 457 glioma cases and 648 population-based controls, all adult men (18-80 yr old) and nonmetropolitan residents of Iowa, Michigan, Minnesota, and Wisconsin. Multiple logistic regressions were used to control for farm residence, age, age group, education, and exposure to other pesticides. No associations were found between glioma and 12 specific pesticides. We estimated adjusted odds ratios (ORs) and 95% confidence intervals (CIS) and found reduced glioma risk for insecticides (OR = 0.53, CI = 0.37-0.77), fumigants (OR = 0.57, CI = 0.34-0.951, and organochlorines (OR = 0.66, CI = 0.47-0.94). in analyses excluding proxy respondents (47% of cases) most CIs included 1.O. No positive association of farm pesticide exposure and glioma was found. Other farm exposures may explain the excess brain cancer risk seen in previous studies.
The National Institute for Occupational Safety and Health evaluated farm pesticide exposure and g... more The National Institute for Occupational Safety and Health evaluated farm pesticide exposure and glioma risk in a study that included 457 glioma cases and 648 population-based controls, all adult men (18-80 yr old) and nonmetropolitan residents of Iowa, Michigan, Minnesota, and Wisconsin. Multiple logistic regressions were used to control for farm residence, age, age group, education, and exposure to other pesticides. No associations were found between glioma and 12 specific pesticides. We estimated adjusted odds ratios (ORs) and 95% confidence intervals (CIS) and found reduced glioma risk for insecticides (OR = 0.53, CI = 0.37-0.77), fumigants (OR = 0.57, CI = 0.34-0.951, and organochlorines (OR = 0.66, Ci = 0.47-0.94). in analyses excluding proxy respondents (47% of cases) most Cis included 1 .O. No positive association of farm pesticide exposure and glioma was found. Other farm exposures may explain the excess brain cancer risk seen in previous studies.
Objective: Glioma is the most common primary malignant brain tumor in adults, responsible for 75%... more Objective: Glioma is the most common primary malignant brain tumor in adults, responsible for 75% of adult primary malignant brain tumors, yet aside from its association with ionizing radiation, its etiology is poorly understood. Sex differences in brain tumor incidence suggest that hormonal factors may play a role in the etiology of these tumors, but few studies have examined this association in detail. The objective of this study was to explore the role of reproductive factors in the etiology of glioma in women. Method: As part of a population-based case-control study, histolog-ically confirmed primary glioma cases (n = 341 women) diagnosed between January 1, 1995 and January 31, 1997 were identified through clinics and hospitals in four Midwest U.S. states. Controls (n = 527 women) were randomly selected from lists of licensed drivers and Health Care Finance Administration enrollees. In-person interviews with subjects (81%) or their proxies (19%) collected reproductive history and other exposure information. Results: Glioma risk increased with older age at men-arche (P for trend = 0.009) but only among postmeno-pausal women. Compared with women who never breast-fed, women who breast-fed >18 months over their lifetime were at increased risk of glioma (odds ratio, 1.8; 95% confidence interval, 1.1-2.9). Women who reported using hormones for symptoms of menopause had a decreased risk of glioma compared with women who never used such hormones (odds ratio, 0.7; 95% confidence interval, 0.5-1.1). Conclusion: These results support the hypothesis that reproductive hormones play a role in the etiology of glioma among women. (Cancer Epidemiol Biomarkers Prev 2004;13(10):1583 – 8)
The commercial aircraft cabin is an often-overlooked indoor environment occupied by both flight c... more The commercial aircraft cabin is an often-overlooked indoor environment occupied by both flight crew and the general public. Endotoxin exposure in indoor environments has been linked to a variety of health conditions. In this study, endotoxin was readily detected in the air and dust of commercial aircraft during passenger flights, and mean air and dust endotoxin levels in the aircraft cabins were generally higher, and more potent, than those reported for homes and offices. Endotoxin levels also varied significantly by dust source (carpet or seat). Density of occupancy, duration of occupancy, and hygienic conditions may partly explain differences across studies.
Exposures to cabin environmental contaminants were measured on 36 commercial transport aircraft. ... more Exposures to cabin environmental contaminants were measured on 36 commercial transport aircraft. The objectives were to characterize levels of contaminants and evaluate the relationship between flight factors such as aircraft size, occupancy, ventilation, and flight length, and environmental parameters. Monitoring was conducted at two coach locations for the duration of the flight for VOCs,
Background NIOSH is conducting health studies of female ¯ight attendants. Exposures of interest i... more Background NIOSH is conducting health studies of female ¯ight attendants. Exposures of interest include cosmic radiation and circadian rhythm disruption, however, the data needed to estimate cumulative radiation dose are not found in work histories. Methods We developed an algorithm to generate from work histories the required input data for Federal Aviation Administration radiation estimation software and evaluated whether effects of cumulative radiation dose could be distinguished analytically from effects of circadian rhythm disruption. Results The algorithm has relatively low bias (` 6%) for longer ¯ights, which contribute most to cumulative radiation dose. In one NIOSH study, 44 crew incurred an estimated average annual occupational dose of 1.5±1.7 mSv. Selection of a study population ¯ying predominantly North±South ¯ights can provide the necessary distinction between radiation and time zone crossing exposures. Conclusions Methods developed will be useful for exposure assessment in cabin crew studies with relatively short study periods, (e.g., reproductive health studies) for which limited ¯ight history details are generally available. Am. J. Ind. Med. 41:27±37, 2002.
—Air crew are exposed to elevated levels of cosmic ionizing radiation of galactic and solar origi... more —Air crew are exposed to elevated levels of cosmic ionizing radiation of galactic and solar origin and are among the more highly exposed occupational groups to ionizing radiation in the United States. Depending on flight route patterns, the annual dose may range from 0.2 to 5 mSv. By comparison, the average annual radiation dose equivalent of occupationally exposed adults in the United States is estimated to be 1.1 mSv. Cosmic-radiation dose depends primarily on altitude and geomagnetic latitude and to a lesser degree on solar activity. Although the International Commission on Radiological Protection has recommended that air crew exposures to natural radiation in-flight be treated as occupational exposures, United States flight crew exposures to natural cosmic radiation are not regulated or typically monitored. There are approximately 148,000 air crew (flight deck crew and flight attendants) in the United States. Health Phys. 79(5):553–559; 2000
The lognormal distribution is often applied to occupational exposures, yet the assumption of logn... more The lognormal distribution is often applied to occupational exposures, yet the assumption of lognormality is rarely verified. This lack of rigor in evaluating the appropriateness of the lognormal model has resulted, in part, from the difficulty of applying formal goodness-of-fit tests. When evaluation of model fit has been attempted, occupational hygienists have relied upon probability plotting of exposures rather than upon formal statistical methods. The goal of this work was to develop for the occupational hygienist a simple quantitative evaluation to supplement the probability plot. A measure of goodness-of-fit to the lognormal model based on the ratio of two estimators of the mean of the distribution, the simple or direct estimate of the mean and the maximum likelihood estimate of the mean of a lognormal distribution, is described. This new measure, the ratio metric, is a simple extension of calculations made routinely by many occupational hygienists. Results from using the ratio metric were compared to probability plotting and to two traditional measures of goodness-of-fit, the Lilliefors test and the W test,for two occupational exposure data sets. The results of the ratio and W tests are comparable for a variety of occupational exposure data, but the Lilliefors test is overly conservative and does not detect several cases of gross deviations from lognormality. The ratio metric is an effective alternative to the Lilliefors test and is easier to perform than the W test for the range of data usually encountered by occupational hygienists. Occupational hygienists are encouraged to use the ratio metric in conjunction with the probability plot in evaluating the lognormal assumption.
Air concentrations were obtained for 55 individual chemical components of gasoline measured by ei... more Air concentrations were obtained for 55 individual chemical components of gasoline measured by eight petroleum companies for service station attendants (n = 491, transport drivers (n = 49), and outside operators (n = 56) during the summer of 1984. Approximate 95 percent confidence intervals were computed for the mean exposures to each of the 55 components in the three job groups. Exposures of service station attendants were significantly lower when vapor recovery systems were present; exposures in the other two job groups were apparently unaffected by vapor recovery systems. The ratios of air concentrations of the 16 most abundant vapor components to the air concentrations of total hydrocarbons (THC) comprised 80-84 percent. It was observed that the vapor ratios calculated in this investigation were similar to those of the same 16 components reported in a previous investigation by McDermott and Killiany in 1978. This apparent stability of vapor ratios suggests the possibility that exposures of individual gasoline components might be estimated solely on the basis of THC measurements. This hypothesis was tested by comparing predicted air levels for 23 hydrocarbons with those actually observed in a recent investigation by Tironi et a/ (1986) and relatively good agreement was observed. Rappaport, S. M.; Selvin, S.; Waters, M. A.: Exposures to hydrocarbon components of gasoline in the petroleum industry. Appl. lnd. Hyg. 2:148-154; 1987.
Journal of occupational and environmental hygiene, Jan 24, 2015
The fundamental goal of this paper is to describe, define and analyze the components of the risk ... more The fundamental goal of this paper is to describe, define and analyze the components of the risk characterization process for occupational exposures. Current methods are described for the probabilistic characterization of exposure, including newer techniques that have increasing applications for assessing data from occupational exposure scenarios. In addition, since the probability of health effects reflects variability in the exposure estimate as well as the dose-response curve - the integrated considerations of variability surrounding both components of the risk characterization provide greater information to the occupational hygienist. Probabilistic tools provide a more informed view of exposure as compared to use of discrete point estimates for these inputs to the risk characterization process. Active use of such tools for exposure and risk assessment will lead to a scientifically supported worker health protection program. Understanding the bases for an occupational risk assess...
Epidemiology, 2006
Production of polychlorinated biphenyls (PCBs) ended in the United States in the 1970s, but PCBs ... more Production of polychlorinated biphenyls (PCBs) ended in the United States in the 1970s, but PCBs persist in the environment and are detectable in the blood of approximately 80% of Americans over age 50. PCBs decrease dopamine levels in rats and monkeys. Loss of dopamine is the hallmark of Parkinson disease, a neurodegenerative disease. There are no epidemiologic studies of PCBs and neurodegenerative disease. We conducted a retrospective mortality study of 17,321 PCB-exposed workers to determine whether mortality from Parkinson disease, dementia, and amyotrophic lateral sclerosis was elevated compared with the U.S. population. All workers had a least 90 days employment in 1 of 3 electrical capacitor plants using PCBs from the 1940s to the 1970s. PCB serum levels from a sample of these workers in the 1970s were approximately 10 times the level of community controls. We found no overall excess of Parkinson disease, amyotrophic lateral sclerosis, or dementia in the PCB-exposed cohort (standardized mortality ratios [SMRs]-1.40, 1.11, and 1.26, respectively, and number of deaths-14, 10, and 28 respectively). However, sex-specific analyses revealed that women had an excess of amyotrophic lateral sclerosis (SMR-2.26; 95% confidence interval [CI] = 1.08-4.15; 10 deaths). Furthermore, among highly exposed women (defined by a job-exposure matrix), we found an excess of Parkinson disease (SMR-2.95; 95% CI = 1.08-6.42; 6 deaths) and dementia (SMR-2.04; 95% CI = 1.12-3.43; 14 deaths). Our data are limited due to small numbers and reliance on mortality rather than incidence data, but are suggestive of an effect of PCBs on neurodegenerative disease for women. The literature does not offer an explanation for why women would be more affected than men by PCB exposure for these outcomes.
AIHce 1997 - Taking Responsibility...Building Tomorrow's Profession Papers, 1997
The objective of this analysis was to evaluate mortality among a cohort of 24,865 capacitor-manuf... more The objective of this analysis was to evaluate mortality among a cohort of 24,865 capacitor-manufacturing workers exposed to polychlorinated biphenyls (PCBs) at plants in Indiana, Massachusetts, and New York and followed for mortality through 2008. Cumulative PCB exposure was estimated using plant-specific job-exposure matrices. External comparisons to US and state-specific populations used standardized mortality ratios, adjusted for gender, race, age and calendar year. Among long-term workers employed 3 months or longer, within-cohort comparisons used standardized rate ratios and multivariable Poisson regression modeling. Through 2008, more than one million person-years at risk and 8749 deaths were accrued. Among long-term employees, all-cause and all-cancer mortality were not elevated; of the a priori outcomes assessed only melanoma mortality was elevated. Mortality was elevated for some outcomes of a priori interest among subgroups of long-term workers: all cancer, intestinal cancer and amyotrophic lateral sclerosis (women); melanoma (men); melanoma and brain and nervous system cancer (Indiana plant); and melanoma and multiple myeloma (New York plant). Standardized rates of stomach and uterine cancer and multiple myeloma mortality increased with estimated cumulative PCB exposure. Poisson regression modeling showed significant associations with estimated cumulative PCB exposure for prostate and stomach cancer mortality. For other outcomes of a priori interest--rectal, liver, ovarian, breast, and thyroid cancer, non-Hodgkin lymphoma, Alzheimer disease, and Parkinson disease--neither elevated mortality nor positive associations with PCB exposure were observed. Associations between estimated cumulative PCB exposure and stomach, uterine, and prostate cancer and myeloma mortality confirmed our previous positive findings.