UN, WHO panel calls hormone-disrupting chemicals a global threat
Rising exposure to chemicals that disrupt and mimic hormones – endocrine disruptors – may present a significant threat to human health, especially that of children in the womb, and to wildlife populations, a new global study of the effect of man-made substances in the environment has concluded. Study produced for the World Health Organisation (WHO) and the United Nations Environment Programme (UNEP).
Women’s Exposures early in Life could unlock Mysteries
” When Ida Washington received a letter inviting her to participate in a women’s health study to explore the environmental roots of breast cancer, she didn’t think twice. Her mother was diagnosed with the disease nearly 40 years ago, and since then, it has been a terrifying mystery she has yearned to unravel.
Washington was just a teenager when the lump was found on her mother’s left breast. In the years that followed, as her mother’s cancer went into remission, she began to wonder what caused it. “My mother didn’t smoke, she didn’t drink. Breast cancer didn’t run in the family,” she said
Ida’s mother, Willie Mae Washington, now 92, participated in the first generation of a scientific study that has endured for more than half a century to investigate whether environmental exposures may trigger breast cancer. Now Ida Washington, 52, is continuing the legacy as part of its second generation.
The two women are among the more than 15,000 mothers, daughters and granddaughters in the San Francisco Bay Area enrolled in a project known as the Child Health and Development Studies, launched in 1959. Tens of thousands of samples of the women’s blood are stored, providing more than 50 years of continuous data on health outcomes and environmental exposures.
Scientists tap into this unique trove as they struggle to figure out what role environmental exposures play in the development of diseases such as breast cancer. ” …
… Continue reading Breast cancer and the environment Part 2: Studied for half a century, these women are ‘a national treasure’, environmentalhealthnews, Feb. 26, 2013.
Studied for half a Century, these Women are “a National Treasure”
” Deep in a laboratory freezer, 100,000 vials of blood have been frozen for the better part of five decades.
For scientist Barbara Cohn, it’s a treasure trove. Collected from more than 15,000 San Francisco Bay Area women after they gave birth in the 1960s, each vial of blood holds a woman’s lifetime of secrets.
Scientists say these vials could help them unravel one of the most enduring medical mysteries: Why do some women, with no family history, develop breast cancer?
The blood bears the chemical signature of environmental pollutants, some long banned, that the women were exposed to decades ago. Cohn, who directs the research in Berkeley, Calif., believes these early-life exposures may hold the key to understanding a woman’s risk of breast cancer today.
The women’s blood is being tested for traces of dozens of pollutants – used by industry and found in many consumer products – that can impersonate estrogen and other hormones. The theory is that early exposure to these chemicals, even before birth, inside the mother’s womb, may fundamentally alter the way that breast tissues grow, triggering cancer decades later.
Cancer patients and their doctors have long puzzled over what factors in a woman’s environment may raise her risk of breast cancer. One of every eight women in the United States is diagnosed with breast cancer during her lifetime, with more than 232,000 new cases diagnosed yearly, according to the American Cancer Society. Only 5 to 10 percent can be accounted for by genetics; other known risk factors include age, obesity and low physical activity. ” …
… Continue reading Breast cancer and the environment Part 1: Women’s exposures early in life could unlock mysteries, environmentalhealthnews, Feb. 26, 2013.
Environmental compounds are known to promote epigenetic transgenerational inheritance of adult onset disease in subsequent generations (F1–F3) following ancestral exposure during fetal gonadal sex determination. The current study was designed to determine if a mixture of plastic derived endocrine disruptor compounds bisphenol-A (BPA), bis(2-ethylhexyl)phthalate (DEHP) and dibutyl phthalate (DBP) at two different doses promoted epigenetic transgenerational inheritance of adult onset disease and associated DNA methylation epimutations in sperm. Gestating F0 generation females were exposed to either the “plastics” or “lower dose plastics” mixture during embryonic days 8 to 14 of gonadal sex determination and the incidence of adult onset disease was evaluated in F1 and F3 generation rats. There were significant increases in the incidence of total disease/abnormalities in F1 and F3 generation male and female animals from plastics lineages. Pubertal abnormalities, testis disease, obesity, and ovarian disease (primary ovarian insufficiency and polycystic ovaries) were increased in the F3 generation animals. Kidney and prostate disease were only observed in the direct fetally exposed F1 generation plastic lineage animals. Analysis of the plastics lineage F3 generation sperm epigenome previously identified 197 differential DNA methylation regions (DMR) in gene promoters, termed epimutations. A number of these transgenerational DMR form a unique direct connection gene network and have previously been shown to correlate with the pathologies identified. Observations demonstrate that a mixture of plastic derived compounds, BPA and phthalates, can promote epigenetic transgenerational inheritance of adult onset disease. The sperm DMR provide potential epigenetic biomarkers for transgenerational disease and/or ancestral environmental exposures.
Gestational exposure to bisphenol a produces transgenerational changes in behaviors and gene expression
Bisphenol-A BPA, DES and similar compounds are known as endocrine-disrupting chemicals, which are substances in the environment that interfere with the proper functioning of hormones.
Bisphenol A (BPA) is a plasticizer and an endocrine-disrupting chemical. It is present in a variety of products used daily including food containers, paper, and dental sealants and is now widely detected in human urine and blood. Exposure to BPA during development may affect brain organization and behavior, perhaps as a consequence of its actions as a steroid hormone agonist/antagonist and/or an epigenetic modifier. Here we show that BPA produces transgenerational alterations in genes and behavior. Female mice received phytoestrogen-free chow with or without BPA before mating and throughout gestation. Plasma levels of BPA in supplemented dams were in a range similar to those measured in humans. Juveniles in the first generation exposed to BPA in utero displayed fewer social interactions as compared with control mice, whereas in later generations (F(2) and F(4)), the effect of BPA was to increase these social interactions. Brains from embryos (embryonic d 18.5) exposed to BPA had lower gene transcript levels for several estrogen receptors, oxytocin, and vasopressin as compared with controls; decreased vasopressin mRNA persisted into the F(4) generation, at which time oxytocin was also reduced but only in males. Thus, exposure to a low dose of BPA, only during gestation, has immediate and long-lasting, transgenerational effects on mRNA in brain and social behaviors. Heritable effects of an endocrine-disrupting chemical have implications for complex neurological diseases and highlight the importance of considering gene-environment interactions in the etiology of complex disease.
Sources and more information
Gestational exposure to bisphenol a produces transgenerational changes in behaviors and gene expression, Endocrinology. 2012 Aug;153(8):3828-38. doi: 10.1210/en.2012-1195. PMID: 22707478 Epub 2012 Jun 15. Full text.
BPA Exposure Effects May Last for Generations, Endocrine Society, press-release-archives/2012.
Toxic Environmental Exposures Could Cause Reproductive Harm Across Generations
Industry likes to say that the risk isn’t so big or the exposures are not so high. But, in fact, these exposures can have far-reaching effects. Unfortunately, regulators are having difficulty even coming to sensible conclusions on direct effects, let alone transgenerational ones.
The actions of environmental toxicants and relevant mixtures in promoting the epigenetic transgenerational inheritance of ovarian disease was investigated with the use of a fungicide, a pesticide mixture, a plastic mixture, dioxin and a hydrocarbon mixture. After transient exposure of an F0 gestating female rat during embryonic gonadal sex determination, the F1 and F3 generation progeny adult onset ovarian disease was assessed. Transgenerational disease phenotypes observed included an increase in cysts resembling human polycystic ovarian disease (PCO) and a decrease in the ovarian primordial follicle pool size resembling primary ovarian insufficiency (POI). The F3 generation granulosa cells were isolated and found to have a transgenerational effect on the transcriptome and epigenome (differential DNA methylation). Epigenetic biomarkers for environmental exposure and associated gene networks were identified. Epigenetic transgenerational inheritance of ovarian disease states was induced by all the different classes of environmental compounds, suggesting a role of environmental epigenetics in ovarian disease etiology.
Read Toxic Environmental Exposures Could Cause Reproductive Harm Across Generations, Study Suggests, huffingtonpost, 2012/05/03.
In a Statement of Principles unveiled today, The Endocrine Society proposes a streamlined definition for endocrine-disrupting chemicals (EDCs) and offers recommendations that will strengthen the ability of current screening programs to identify EDCs.
An endocrine-disrupting chemical (EDC) is an exogenous chemical, or mixture of chemicals, that can interfere with any aspect of hormone action. The potential for deleterious effects of EDC must be considered relative to the regulation of hormone synthesis, secretion, and actions and the variability in regulation of these events across the life cycle. The developmental age at which EDC exposures occur is a critical consideration in understanding their effects. Because endocrine systems exhibit tissue-, cell-, and receptor-specific actions during the life cycle, EDC can produce complex, mosaic effects. This complexity causes difficulty when a static approach to toxicity through endocrine mechanisms driven by rigid guidelines is used to identify EDC and manage risk to human and wildlife populations. We propose that principles taken from fundamental endocrinology be employed to identify EDC and manage their risk to exposed populations. We emphasize the importance of developmental stage and, in particular, the realization that exposure to a presumptive “safe” dose of chemical may impact a life stage when there is normally no endogenous hormone exposure, thereby underscoring the potential for very low-dose EDC exposures to have potent and irreversible effects. Finally, with regard to the current program designed to detect putative EDC, namely, the Endocrine Disruptor Screening Program, we offer recommendations for strengthening this program through the incorporation of basic endocrine principles to promote further understanding of complex EDC effects, especially due to developmental exposures.
Read Endocrine-Disrupting Chemicals and Public Health Protection: A Statement of Principles from The Endocrine Society, Endocrinology. doi: 10.1210/en.2012-1422, 2012 Sep; 153(9): 4097–4110.
Why ask Zebrafish how body parts react to endocrine disruptors, ask DES mothers, daughters and sons instead! They know too well how DES, the first chemical known to act as an endocrine disruptor, messes up with your whole body and health …!!!