Hairspray Link to Genital Birth Defects

Nov. 23, 2008— -- Pregnant hairdressers may be exposing their unborn children to harmful chemicals that can lead to genital birth defects.

A new study shows that the sons of hairdressers and beauticians frequently exposed to hairspray were more than twice as likely to be born with hypospadias, in which the urinary opening appears on the underside of the penis.

Paul Elliott from Imperial College London, and colleagues, interviewed 471 mothers whose sons had been born with the defect and 490 mothers of children not born with the disorder, to try to find out which chemicals the mothers had been exposed to: including exhaust fumes, printing ink, hairspray, or glues.

While the other substances did not return statistically significant results, the use of hairspray appeared to have a big impact. Of the 74 women who reported regular exposure to hairspray at work during the first three months of pregnancy, 50 gave birth to sons with the genital defect.

In contrast, the proportion of children born with the defect was much lower in women who did not report being in regular contact with hairspray – just 294 out of 618. Overall, the study found that women exposed to hairspray were 2.3 times more likely to have children with the defects.

Plastic Worries

The team suggests a group of chemicals called phthalates that are found within hairspray may be to blame.

Phthalates are known to interfere with hormones associated with the development of the reproductive system.

The chemicals have been banned in hairsprays and cosmetic products in the EU since 2005, but not in the US, where they are only banned for use in children's toys. Elliot's study looked at British children born before the ban.

Alarm bells had been raised when a study found elevated levels of the toxins in babies' teething rings. And since phthalates are commonly used in the pharmaceutical and plastics industry, particularly in the US, the team suggest other women besides hairdressers and beauticians may also be putting their children at risk.

Hypospadias can usually be corrected with simple surgery, although it can occasionally lead to sexual dysfunction and infertility.

Veggies in the Clear

The real worry, says Elliott, is that pregnant women may be exposing their children to other harmful chemicals that interfere with the body's hormones and we don't yet understand the full effects.

"There are a range of chemicals that could affect [male hormones] in developing fetuses – like oestrogens used in pharmaceutical products and which are also found in small quantities in the water supply," he says.

The research does bring some good news to pregnant women, however. The team found that women who take folic-acid supplements are 36% less likely to give birth to children with the disorder.

In addition, vegetarianism – which had been linked to cases of hypospadias in a previous smaller study – turned out to have no impact on the risk of giving birth to children with this birth defect.

Tim Edgar, from industry group the European Council for Plasticisers and Intermediates, said the study should be treated with caution.

"I'm very concerned about a so-called scientific study that asks a group of ladies to try to remember what they might have been subjected to prior to giving birth," he said.