Over the past few years, researchers have been scrambling to figure out why the average age of menarche — the age when a girl has her first period — has been on the decline. In the last several decades, that age has fallen from an average of 16 to 17 to closer to 12 or 13. But why?
Several studies have linked rising obesity rates to early puberty, but a new study has found another intriguing link — chemical exposure. Could exposure to a common household chemical contribute to the early onset of puberty?
, conducted by the Centers for Disease Control and Prevention (CDC), specifically looked at the chemical dichlorobenzene, a solvent, that is used in some mothballs, toilet bowl deodorizers and air fresheners. It is found in the bloodstream or urine of almost all people tested in this country. Exposure occurs primarily via the air we breathe.
The CDC study found that girls exposed to high levels of dichlorobenzene had their first period seven months earlier than girls with lower exposures. Danielle Buttke, the study’s lead author and a reproductive physiologist at the CDC commented, “[t]his study adds to the growing body of scientific research that exposure to environmental chemicals may be associated with early puberty.”
Regardless of the cause, earlier menarche is a problem for young girls. It has been linked to an increased risk for breast cancer and other diseases in adulthood, as well as behavioral disorders
in the tween/teen years.