“The negative effects of PCB153 in neurodevelopment are mainly attributed to prenatal exposure”

14/03/2013

Although during lactation the exposure to certain persistent organic pollutants (POPs) increases regarding pregnancy during the exposure, the negative effects of PCB153 in neurodevelopment, particularly in psychomotor development, are mainly attributed to prenatal exposure.This is the main conclusion of the study “Evaluating the neurotoxic effects of lactational exposure to persistent organic pollutants (POPs) in Spanish children” developed by INMA Project Investigators.

To date, many studies had shown an association between exposure to these compounds during pregnancy and effects on neurodevelopment of children. However, the evidence on the effects of postnatal exposure (after birth) exposure to these compounds, which is mainly due to lactation-were much less clear. One of the main factors limiting the study of the effects of postnatal exposure was estimated that the exposure was carried out in a very simple form that did not account for variation of exposure over the first month of life baby.

In this new study, led by researcher Martine Vrijheid, some models have been applied -called pharmacokinetic- that have allowed the authors to estimate levels of exposure, month by month during the first year of baby’s life. Thus, it has been studied more thoroughly if exposure to OCs, specifically PCB153, DDE and HCB, during lactation had a negative effect on neurodevelopment of children, and also see which month or months of the first year of life was so.

With this new method of analysis, the study confirms that although the levels of organochlorine compounds in children increases during the months of lactation, it is during the prenatal phase when exposure to these compounds can have an effect more negative for the baby. Although lactation increases exposure, it is recommended for the many benefits that breast milk have for baby neurodevelopment.

These effects, more evidently from the second year of life, can affect the neurodevelopment of the child and are related to deficiencies in areas such as executive functions, which are vital for the control of behaviour and cognition.Effects have also been observed in preteen age children, in very specific functions like processing speed. The authors note that these effects are at the population level and are in no way clinical neurodevelopmental deviations. That is, you can not predict that a child with high levels of OCs will develop neurodevelopmental pathology.

Paper: Gascon M, Verner MA, Guxens M, Grimalt JO, Forns J, Ibarluzea J, Lertxundi N, Ballester F, Llop S, Haddad S, Sunyer J, Vrijheid M. “Evaluating the neurotoxic effects of lactational exposure to persistent organic pollutants (POPs) in Spanish children”.