Characterization of Potential Endocrine-Related Health Effects at Low-Dose Levels of Exposure to PCBs

Abstract

This article addresses issues related to the characterization of endocrine-related health effects resulting from low-level exposures to polychlorinated biphenyls (PCBs). It is not intended to be a comprehensive review of the literature but reflects workshop discussions. "The Characterizing the Effects of Endocrine Disruptors on Human Health at Environmental Exposure Levels," workshop provided a forum to discuss the methods and data needed to improve risk assessments of endocrine disruptors. This article contains an overview of endocrine-related (estrogen and thyroid system) interactions and other low-dose effects of PCBs. The data set on endocrine effects includes results obtained from mechanistic methods/ and models (receptor based, metabolism based, and transport protein based), as well as from in vivo models, including studies with experimental animals and wildlife species. Other low-dose effects induced by PCBs, such as neurodevelopmental and reproductive effects and endocrine-sensitive tumors, have been evaluated with respect to a possible causative linkage with PCB-induced alterations in endocrine systems. In addition, studies of low-dose exposure and effects in human populations are presented and critically evaluated. A list of conclusions and recommendations is included.

Xenobiotic action on steroid hormone synthesis and sulfonation the example of lead and polychlorinated biphenyls

“…A wide variety of endocrine functions are aVected by PCBs, including the estrogen and androgen systems, the thyroid system, the retinoid system, the corticosteroid system and other endrocrine pathways. Of particular interest is their estrogenic activity, which is thought to play an important role in the impaired sexual diVerentiation and reproductive dysfunction observed in birds, Wsh, reptiles and mammals that have been exposed (Brouwer et al 1999). Antiestrogenic eVects of PCBs were found for PCB congeners 138, 153 and 180 (Bonefeld-Jorgensen et al 2001); Kester et al (2000) demonstrated that hydroxylated PCB metabolites inhibited estrogen sulfotransferase (SULT1E1).…”

“…Many diVerent enzyme systems are involved in the synthesis, intracellular bioactivation and degradation of steroids including cytochrome P450 isozymes, uridine-5-diphosphate-glucuronyltransferases (UGTs) and sulfotransferases (SULTs) (Brouwer et al 1999).…”

Community Health Profile of Windsor, Ontario, Canada: Anatomy of a Great Lakes Area of Concern

“…The 22% higher rate of other disorders of the female genital tract resulted in 733 excess cases for those 25-44 years of age, and even the 5% higher rate for those 44 The rates of morbidity as hospitalization cases for diseases of the musculoskeletal system and connective tissues in the population of the Windsor Area of Concern were significantly elevated for the following: arthropathies and related diseases (12% for males, 11% for females); dorsopathies (26% for males, 21% for females); rheumatism, excluding the back (2-fold for males, 88% increase for females); and osteopathies, chondropathies, and acquired musculoskeletal deformities (27% for males, 30% for females). These elevated rates tended to occur in all age classes up to 75 years of age.…”

Environmental and dietary endocrine disruptors and women's health

“…9,28 Others have reported that exposure to high levels of PCB or dioxins is associated with changes in thyroid function, with elevation of thyroid stimulating hormone (TSH), which could in turn adversely affect neurodevelopment. 13 Increasing numbers of studies are also reporting evidence for in utero exposure to suspect chemicals. For example, a high frequency of potential endocrine disrupting chemicals (such as a-HCH, p,p'-DDE and some PCBs) have been found in the amniotic fluid of women undergoing routine amniocentesis in Los Angeles, USA.…”