Associations of concurrent PCB and PBDE serum concentrations with executive functioning in adolescents.

Polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are ubiquitous environmental chemicals that have long half-lives. Humans are exposed to PCBs and PBDEs mainly through diet, and relative to other populations, those who consume sport-caught fish generally have elevated body burdens. Numerous studies have found associations between prenatal exposure to these chemicals and neurodevelopmental deficits, but there are few studies assessing the impact of exposure during adolescence, a period of rapid development of executive functions.

Effect of exposure to 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs) on mitochondrial DNA (mtDNA) copy number in rats.

Mitochondria are intracellular organelles responsible for biological oxidation and energy production. These organelles are susceptible to damage from oxidative stress and compensate for damage by increasing the number of copies of their own genome, mitochondrial DNA (mtDNA). Cancer and environmental exposure to some pollutants have also been associated with altered mtDNA copy number.

Telomeres as targets for the toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs) in rats.

Telomere length (TL) can be affected by various factors, including age and oxidative stress. Changes in TL have been associated with chronic disease, including a higher risk for several types of cancer. Environmental exposure of humans to PCBs and dioxins has been associated with longer or shorter leukocyte TL.

Organochlorine pesticide residues in human breast tissue and their relationships with clinical and pathological characteristics of breast cancer.

Agricultural pesticides are abundant environmental contaminants worldwide, prompting interest in studying their possible detrimental health effects. We examined organochlorine residues by quadrant (n = 245) in breast adipose tissues from 51 women with various stages of breast health to determine patterns of bioaccumulation within the breast and to assess relationships with patient clinical characteristics. Three organochlorine residues-2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (p,p'-DDE), hexachlorobenzene (HCB), and mirex-assayed by high resolution gas chromatography were abundant in breast tissue.

Abundance and distribution of polychlorinated biphenyls (PCBs) in breast tissue.

Many environmental chemicals accumulate in human tissues and may contribute to cancer risk. Polychlorinated biphenyls (PCBs) are associated with adverse health effects, but relationships between PCB exposure and breast cancer are unclear. In this study, we sought to determine whether bioaccumulation of PCBs differs within regions of the human breast and whether PCB levels are associated with clinical and pathological characteristics in breast cancer patients.