Brain cancer mortality and potential occupational exposure to lead: Findings from the National Longitudinal Mortality Study, 1979–1989

Abstract

We evaluated the association between potential occupational lead exposure and the risk of brain cancer mortality in the National Longitudinal Mortality Study (NLMS), which is a prospective census-based cohort study of mortality among the noninstitutionalized United States population (1979)(1980)(1981)(1982)(1983)(1984)(1985)(1986)(1987)(1988)(1989). The present study was limited to individuals for whom occupation and industry were available (n 5 317,968). Estimates of probability and intensity of lead exposure were assigned using a job-exposure matrix (JEM). Risk estimates for the impact of lead on brain cancer mortality were computed using standardized mortality ratio (SMR) and proportional hazards and Poisson regression techniques, adjusting for the effects of age, gender and several other covariates. Brain cancer mortality rates were greater among individuals in jobs potentially involving lead exposure as compared to those unexposed (age-and gender-adjusted hazard ratio (HR) 5 1.5; 95% confidence interval (CI) 5 0.9-2.3) with indications of an exposure-response trend (probability: low HR 5 0.7 (95% CI 5 0.2-2.2), medium HR 5 1.4 (95% CI 5 0.8-2.5), high HR 5 2.2 (95% CI 5 1.2-4.0); intensity: low HR 5 1.2 (95% CI 5 0.7-2.1), medium/high HR 5 1.9 (95% CI 5 1.0-3.4)). Brain cancer risk was greatest among individuals with the highest levels of probability and intensity (HR 5 2.3; 95% CI 5 1.3-4.2). These findings provide further support for an association between occupational lead exposure and brain cancer mortality, but need to be interpreted cautiously due to the consideration of brain cancer as one disease entity and the absence of biological measures of lead exposure. ' 2006 Wiley-Liss, Inc.

Lead, Genetic Susceptibility, and Risk of Adult Brain Tumors

“…However, risk of meningioma was consistently increased with all lead exposure metrics for individuals carrying the ALAD2 allele. Previous studies with more rudimentary exposure information have reported an overall increase in meningioma risk with lead exposure (3,(7)(8)(9). Although these studies did not examine possible susceptibility by ALAD genotype, we would expect that if their study populations had only a small proportion of high-risk individuals, lesser magnitudes of overall risk would have been reported than we observed for patients with the ALAD2 allele.…”

“…Whereas some epidemiologic studies have described increased risk of brain tumors with potential lead exposure (3)(4)(5)(6), particularly for meningioma (7)(8)(9), other evaluations report no significant association between lead and brain cancer (10)(11)(12). The inconsistency of previous reports may be due to small numbers of brain tumor cases, limited exposure assessment for lead, or lack of consideration of brain tumor type.…”

Serum Levels of Trace Elements in Patients with Prostate Cancer

“…It is well-known that Pb and Cd are toxic and carcinogenic metals (Nawrot et al, 2002). It has been suggested that Pb has a facilitating role in the carcinogenesis through inhibition of DNA synthesis and repair, oxidative injury and interaction with DNA-binding proteins and tumor suppressor proteins (Inskip et al, 1995;Wijngaarden and Dosemeci, 2006). In humans, increased carcinogenic elements may be associated to a variety of disorders.…”

Regulation of Metabolites, Gene Expression, and Antioxidant Enzymes to Environmentally Relevant Lead and Zinc in the Halophyte Suaeda salsa

“…Obviously, all three heavymetal exposures inhibited plant growth after 15 days. As a known toxicant to organisms, lead can induce various types of toxicity, including genotoxicity, immunotoxicity, and nephrotoxicity, and can inhibit the growth of organisms (Zurich and others 2002;van Wijngaarden and Dosemeci 2006;Jain and others 2007). Conjecturally, lead should inhibit the growth of plants; this was observed in this work.…”

“…Among these heavy-metal contaminants, lead and zinc concentrations have been up to 70 and 120 lg L -1 in seawater from the Bohai Sea, respectively (Zhang 2001;Mao and others 2009). Lead is a nonessential element for organisms and causes various toxicities, including neurotoxicity, nephrotoxicity, cardiovascular disease, genotoxicity, immunotoxicity, and carcinogenicity in animals (Zurich and others 2002;van Wijngaarden and Dosemeci 2006;Jain and others 2007). Zinc is essential to organisms; however, excessive Zn can induce potential toxicities such as genotoxicity and immunotoxicity in vertebrates (Hogstrand and Wood 1996).…”