Prenatal exposure to phthalates could affect infant behaviour

Phthalates are a large class of compounds some of which are found in cosmetic products such as fragrances and nail varnishes.

According to a study recently published in the Environmental Health Perspectives online journal, prenatal exposure to high levels of low molecular weight phthalates (including those that are found in some cosmetic products, for example diethyl phthalate (DEP)) were associated with behavioural problems in children.

The study, led by Dr Stephanie Engel of the Mount Sinai School of Medicine, took urine samples from 177 women who were enrolled for prenatal care either at the Mount Sinai Diagnostic Treatment Center or at two private practices on the Upper East Side of Manhatten.

These urine samples (which were taken between 25 and 40 weeks into the pregnancy) were analysed for ten phthalate metabolites that were divided into two groups, high molecular weight and low molecular weight, to limit the number of statistical tests performed.

Women were invited for three follow up visits when their children were between 4 and 9 years old, and behavioural questionnaires were administered.

Parental judgements on behaviour​

The parent-report sections of both the Behaviour Rating Inventory of Executive Functioning (BRIEF) and the Behaviour Assessment System for Children (BASC-PRS) were completed by the mothers at each visit.

Poorer scores on BASC indexes such as aggression, attention problems, conduct problems and depression, were associated with higher maternal levels of low molecular weight phthalates, the scientists claimed.

In addition, higher scores on the BRIEF scales such as emotional control were also associated with higher phthalate levels.

The behaviours recorded in the study do not meet the ‘at risk’ or ‘clinically significant’ criteria, note the researchers. However, they argue that the findings warrant additional study on the role of prenatal exposure to low molecular weight phthalates in the emergence of disruptive behaviour problems in children.

Although the researchers are unsure of a mechanism behind these effects, they postulate it could be linked to phthalates’ potential endocrine effects and conclude the more research is ‘urgently needed’​ in order to replicate the findings.

If the findings were to be replicated, limits to prenatal exposure may need to be put in place, the researchers argued.

DEP review in 2007​

In 2007 the European Commission’s independent scientific committee the SCCP (now the SCCS, Scientific Committee on Consumer Safety) approved the use of DEP (the main phthalate used in Europe) in cosmetic products and did not pose any specific warnings or restrictions on its use.

Source: Environmental Health Perspectives​
​doi: 10.1289/ehp.0901470
Prenatal phthalate exposure is associated with childhood behavior and executive functioning​
​Stephanie M. Engel, Amir Miodovnik, Richard L. Canfield, Chenbo Zhu, Manori J. Silva, Antonia M. Calafat and Mary S. Wolff