James Morel Symons

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PURPOSE Based on previous reports of increased serum lipid levels in workers at a U.S. polymer manufacturing facility, the study objective was to investigate ischemic heart disease (IHD) mortality as well as a broad range of mortality causes for an occupational cohort at the facility. METHODS The cohort comprised 6,027 men and women who had worked at the(More)
Three of us (G.M., A.Y., and P.M.) performed reanalyses of the National Cancer Institute cohort study on nasopharyngeal cancer (NPC) risk among formaldehyde exposed workers (Hauptmann et al., 2004). Both reanalyses (Marsh and Youk, 2005; Marsh et al., 2007) were published in this journal. However, the mortality follow-up performed by the NCI working group(More)
The case-crossover design has been increasingly applied to epidemiologic investigations of acute adverse health effects associated with ambient air pollution. The correspondence of the design to that of matched case-control studies makes it inferentially appealing for epidemiologic studies. Case-crossover analyses generally use conditional logistic(More)
With increasing evidence of adverse health effects associated with particulate matter (PM), the exposure impact of natural sources, such as forest fires, has substantial public health relevance. In addition to the threat to nearby communities, pollutants released from forest fires can travel thousands of kilometers to heavily populated urban areas. There(More)
In 2004, the International Agency for Research on Cancer (IARC) reclassified formaldehyde (FA) from a probable (Group 2A) to a known human carcinogen (Group 1) citing results for nasopharyngeal cancer (NPC) mortality from the follow-up through 1994 of the National Cancer Institute formaldehyde cohort study. To the contrary, in 2012, the Committee for Risk(More)
The destruction of the World Trade Center (WTC) in New York City on September 11, 2001, created a 16-acre debris field composed of pulverized and burning material significantly impacting air quality. Site cleanup began almost immediately. Cleanup workers were potentially exposed to airborne contaminants, including particulate matter, volatile organic(More)
BACKGROUND There is a recognized need to improve the application of epidemiologic data in human health risk assessment especially for understanding and characterizing risks from environmental and occupational exposures. Although there is uncertainty associated with the results of most epidemiologic studies, techniques exist to characterize uncertainty that(More)
This study investigated the control of trihalomethanes (THMs) with ion exchange by comparing the THM formation potentials of the organic fractions in the influent to three column systems. The results showed that the smallest organic fraction, <0.5 K apparent molecular weight (AMW), was most reactive with free available chlorine. With the ion exchange(More)
OBJECTIVE To evaluate the influence of community- and family-level factors on racial/ethnic disparities in the uptake of nongroup (individual) health insurance. DATA SOURCES Responses to the 1996-1997 Community Tracking Study Household Survey plus community-level descriptors from several sources including census data, the Area Resource File, and community(More)
OBJECTIVE The investigation updates the mortality experience through 2002 for a cohort of workers exposed to acrylonitrile (AN). METHODS Standardized mortality ratios (SMR) were estimated based on two reference populations: the US population and a regional employee population. Exposure-response analyses were conducted using Cox regression models for(More)