Subjects: Public health
Boys born to women that had significant occupational exposure to hair spray while pregnant are twice as likely to develop a certain urogenital abnormality according to a study in Environmental Health Perspectives.
The abnormality is known as hypospadias, in which the urethra exits the body on the underside of the penis rather than at the tip. Hypospadias is generally corrected surgically during the first year of life and there are few long term sequelae after the repair.
Paul Elliott and his team at Imperial College, London reported the association after using a retrospective, case-control study design to compare 471 hypospadias cases from the London area with controls randomly selected from a birth registry.
They obtained detailed histories regarding maternal age, education, folate supplementation, income, occupation, smoking and vegetarianism.
They also inquired about occupational exposure during pregnancy to toxins and carcinogens which are found in disinfectants, hair spray, paints, pesticides, plastics and printing ink.
The scientists believe the hair spray risk is related to phthalates, organic compounds that are often used in plastics manufacturing. Phthalates are also found in cosmetics, deodorants, fragrances, nail polish and hair products.
Phthalates disrupt androgen synthesis, and low levels of the male sex hormone are known to cause male reproductive tract abnormalities like hypospadias.
In case you were wondering, hair spray contains lots more inhalable toxins including polyvinyl alcohol, polyvinylpyrolidone and so on but wouldn’t you know it? These other ones aren’t toxic to male sex hormone synthesis, only the skin, eyes and cardio-respiratory system.