On October 21, 2014 the peer-reviewed scientific Journal of Epidemiology and Community Health published a new study stressing the need to evaluate the cumulative effects of environmental chemicals. The authors argue that the increasing prevalence of disorders such as autism cannot solely have a genetic cause. They suggest that the ubiquitous exposure to environmental chemicals, especially prenatal and early-life exposures, may be contributing to this increase.
Humans are exposed to environmental chemicals from a variety of sources including the food we eat daily. Maffini and Neltner identified more than 300 chemicals allowed in food that may adversely affect brain development. They explain that on one side the individual substances may or may not have a harmful effect on their own; on the other side, they may have effects in the mixture. The authors stress that there is a significant lack of knowledge regarding the cumulative effects of these chemicals on the developing brain. The current chemical risk assessment approach typically considers toxicity of single chemicals only, but not simultaneous exposures to various chemicals affecting the same organ or system. The authors emphasize that a collective effort of the expert community is needed to revise the current chemical risk assessment approach to include the effects of cumulative chemical exposures on organs and their role in chronic diseases.
Maffini, M.V. and Neltner, T.G. (2014). “Brain drain: the cost of neglected responsibilities in evaluating cumulative effects of environmental chemicals” Journal of Epidemiology and Community Health (published online October 21, 2014).