{"id":3038,"date":"2014-02-18T09:41:10","date_gmt":"2014-02-18T14:41:10","guid":{"rendered":"http:\/\/blogs.edf.org\/health\/?p=3038"},"modified":"2014-03-25T12:44:55","modified_gmt":"2014-03-25T17:44:55","slug":"unnerving-developments-in-the-state-of-the-evidence-on-developmental-neurotoxicity","status":"publish","type":"post","link":"https:\/\/blogs.edf.org\/health\/2014\/02\/18\/unnerving-developments-in-the-state-of-the-evidence-on-developmental-neurotoxicity\/","title":{"rendered":"Unnerving developments in the state of the evidence on developmental neurotoxicity"},"content":{"rendered":"

Rachel Shaffer<\/em> is a research assistant.<\/p>\n

Seven years ago, leading children\u2019s environmental health experts Philippe Grandjean and Philip Landrigan published a groundbreaking <\/span>review<\/span><\/a> that identified five chemicals prevalent in the environment\u2014lead, methylmercury, polychlorinated biphenyls (PCBs), arsenic, and toluene\u2014as developmental neurotoxicants.\u00a0In their follow-up <\/span>review<\/span><\/a> released last week, they have added six more chemicals\u2014manganese, fluoride, polybrominated diphenyl ethers (PBDEs), chlorpyrifos, DDT, and tetrachloroethylene (PERC)\u2014to this list. The implications of early-life exposures to these common compounds, say the authors? \u00a0A \u201cglobal silent pandemic of neurodevelopmental toxicity.\u201d\u00a0 <\/span><\/span><\/span><\/p>\n

The developing fetus and newborn are uniquely susceptible to chemical exposures, and disruptions to critical developmental \u201cprogramming\u201d during this sensitive period can have life-long consequences. \u00a0In the environmental health field, this concept is known as the \u201c<\/span>Developmental Origins of Health and Disease<\/span><\/a>\u201d and suggests that even low-level exposures that would have little or no effect on adults could forever alter the development and life-course of a newborn or young child. <\/span><\/span><\/span><\/p>\n

The individual and societal consequences of early-life exposures to developmental neurotoxicants can be devastating. \u00a0Damage to the brain can lead to permanent decreases in IQ or developmental disabilities, which in turn have implications for academic potential, earning capacity, and, at a population level, effects on national gross domestic product (GDP). \u00a0Research also suggests that these developmental neurotoxicants can lead to antisocial or criminal behavior; evidence is particularly strong for the case of <\/span>lead<\/span><\/a>. \u00a0Yet, in contrast to high-dose poisoning events, effects of these exposures can be subtle and often do not manifest until years later, making it difficult to identify and characterize the linkages to chemical exposures. <\/span><\/span><\/span><\/p>\n

Based on mounting data from recent epidemiological studies, Grandjean and Landrigan have now classified the following compounds as known human developmental neurotoxicants: <\/span><\/span><\/span><\/p>\n