Polychlorinated biphenyls (PCBs) and a number of pesticides can act as endocrine disrupting compounds (EDCs). These molecules exhibit hormonal activity in vivo, and can therefore interact and perturb normal physiological functions. Many of these compounds are persistent in the environment, and their bioaccumulation may constitute a significant threat for human health. 

Physiological abnormalities following exposure to these xenobiotic compounds go along with alterations at the protein level of individual cells. In this study, MCF-7 cells were exposed to environmentally relevant concentrations of atrazine, PCB153 (100ppb, respectively), 17-ss estradiol (positive control, 10nM) and a negative control (solvent) for t=24h (n=3 replicates/exposure group). After trizol extraction and protein solubilisation, protein expression levels were studied by 2D-DiGE. Proteins differentially expressed were excised, trypsin-digested, and identified by MALDI-ToF-ToF, followed by NCBInr database search. 2D-DiGE experiments demonstrated that 49 spots corresponding to 29 proteins were significantly differentially expressed in MCF-7 cells (>1.5 fold, P<0.05, Student’s paired T-test). 

These proteins belonged to various cellular compartments (nucleus, cytosol, membrane), and varied in function; 88% of proteins were down-regulated during atrazine exposure whereas 75% of proteins were up-regulated by PCB153. Affected proteins included those regulating oxidative stress such as superoxide dismutase and structural proteins such as actin or tropomyosin, which may explain morphological changes of cells already observed under the microscope. This study highlights the susceptibility of human cells to compounds with endocrine disrupting properties. 

Reference: Lasserre JP, Fack F, Revets D, Planchon S, Renaut J, Hoffmann L, Gutleb AC, Muller CP, Torsten B., Effects of the endocrine disruptors Atrazine and PCB 153 on the Protein Expression of MCF-7 human cells, J Proteome Res. 2009 Sep 25.

Endocrine disrupting compounds (EDCs) and pharmaceuticals and personal care products (PPCPs) in the aquatic environment: implications for the drinking water industry and global environmental health

Endocrine disrupting compounds (EDCs) and pharmaceuticals and personal care products (PPCPs) are a group of chemical compounds with diverse physical and chemical properties. Recent studies have indicated undesired effects of EDCs and PPCPs at their reported trace concentrations (ng l(-1) to microg l(-1)). 

This paper reviews the current knowledge on the sources, properties, occurrence and health impacts of EDCs and PPCPs, and their removal from drinking water using ozonation and ozone/hydrogen peroxide-based advanced oxidation. The paper also examines the potential threats posed by these chemicals to drinking water and public health. While these compounds are known to have adverse effects on ecosystem health, notably in the fish population, a similar link is yet to be established between ingestion of these compounds through drinking water and human health. In addition, data on the effectiveness of existing methods for the removal of these compounds are not conclusive.

Further studies are required to characterize risks, and also to evaluate and optimize existing removal processes. Also concerted international effort is urgent to cut down the risk of exposure and restrain the production and marketing of toxic chemicals.

Reference:  Rahman MF, Yanful EK, Jasim SY., Endocrine disrupting compounds (EDCs) and pharmaceuticals and personal care products (PPCPs) in the aquatic environment: implications for the drinking water industry and global environmental health, Department of Civil and Environmental Engineering, The University of Western Ontario, J Water Health. 2009 Jun;7(2):224-43. 

Racial disparities in pregnancy outcome in the United States are significant, persistent and costly, but the causes are poorly understood. We propose that disproportionate exposure of African-American women to environmental endocrine disrupting compounds (EDCs) may contribute to birth outcome disparities. Marked racial segregation, as well as health behaviors associated with poverty could result in differences in exposure to particular EDCs. One EDC that has aroused concern in recent years is bisphenol-A (BPA), a widely used industrial plasticizer with known estrogenic properties.

Published studies indicate that excessive BPA exposure is associated with reduced fetal survival, as well as reductions in maternal weight and fetal body weight. Related findings include adverse effects of BPA exposure on ovarian function, mammary gland development, earlier age of puberty onset and some metabolic parameters. However, these findings are largely limited to experimental animal studies, and need to be validated in human populations.

Our review supports the need to move beyond the currently dominant toxicological approach to examining the effects of BPA exposure, and rely more on observational human studies and epidemiological methods. Many of the risk factors for racial disparities in pregnancy outcome are global or difficult to modify, but exposure to BPA is a potentially malleable risk factor. If BPA contributes to racial disparities in pregnancy outcome, there are important implications for prevention. It is our hope that this review will stimulate further research in this important and neglected area.

Reference: Ranjit N, Siefert K, Padmanabhan V., Bisphenol-A and disparities in birth outcomes: a review and directions for future research, Journal of Perinatology advance online publication, 9 July 2009; doi:10.1038/jp.2009.90.