Phthalate exposure may impact onset of puberty

A new study suggested that prenatal exposure to certain phthalates may be associated with a slightly earlier onset of puberty.

The study, published in the journal, Environmental Research, was led by Carmen Freire, PhD, a researcher at the Biosanitary Research Institute of Granada.Freire and her team of researchers aimed to discover if there was a connection between prenatal phthalate exposure and pubertal development in both male and female children.

The study involved 788 children enrolled in the INMA Project which studies the impact of environmental pollutants of children’s growth and development. Researchers measured the children’s prenatal exposure to phthalates through urine samples collected during their mother’s pregnancy. Information regarding the children’s pubertal development was collected through a questionnaire filled out by their parents. The body mass index of each participant was also collected as obesity can play a role in puberty onset, according to the study. Children were categorized into five stages of sexual development including pre-puberty, early puberty, mid-puberty, late puberty, and post-puberty.

The study’s results showed phthalates were present in more than  99 percent of the urine samples. Overall, scientists observed that higher prenatal exposure to phthalates was associated with a slightly increased risk of early puberty onset. In both male and female children scientists observed that prenatal exposure to di-(2-ethylhexyl) phthalate (DEHP), a substance used in certain plastics, was linked to a greater risk of early puberty onset. Prenatal exposure to DEHP, di-ethyl phthalate (DEP) and di-n-butyl phthalate (DnBP) was associated with an earlier onset of puberty in normal weight boys while exposure to butyl benzyl phthalate (BBzP) and di-iso-nonyl-cyclohexane-1,2-dicarboxylate (DINCH) was associated with a later onset of puberty in overweight boys. For overweight and obese girls, exposure to di-iso-butyl phthalate (DiBP), DnBP, and DINCH was associated with a slightly early onset of puberty.

“We cannot affirm that phthalates are associated with precocious puberty as a clinical pathology, as we did not assess when this process started in each participant,” said Freire in a statement. “What is clear is that the age at puberty onset has decreased in recent decades and our findings suggest that phthalates could be one of the factors involved.”