If you’re like most women and men, you start each day by slathering yourself top to toe in a bevy of beauty and grooming goos, including cleansers, cosmetics and fragrances. Which is nothing next to the bounty of brands we use to clean, grease, straighten, style and color our ’dos.

However, health groups are raising concerns about possible health effects of long-term exposure to these substances. Recently, California began enforcing legislation (the first of its kind) requiring cosmetic companies to inform state health authorities when their brands contain potentially harmful chemicals. Should you fear what’s on your bathroom shelves? Real Health takes a look.

CLAIM A common shampoo ingredient, sodium laureth sulfate (SLES), causes cancer.
FACT Rumors that SLES and another shampoo sudsing agent, sodium lauryl sulfate (SLS), might be carcinogenic date back decades. But according to the American Cancer Society, though both can irritate skin and eyes, they aren’t known to cause cancer.

CLAIM Hair products contain hormones that raise breast cancer risk.
FACT A study at the University of Pittsburgh found that a common factor among black girls who developed breasts as toddlers was that their mothers had been treating the girls’ hair with products that contained hormones. Researchers continue to examine the link, but increased exposure to hormones is known to up one’s risk for breast cancer.

CLAIM Relaxers cause birth defects.
FACT A 1999 study concluded that using relaxers during pregnancy does not increase the chance of low birth weight or pre-term delivery. However, small amounts of relaxer chemicals may be absorbed into your body, so your fetus might be exposed to them too.

CLAIM Hair dye causes cancer.
FACT A recent study did report that people who colored their hair had an increased risk of developing lymphoma, a form of cancer. However, most cases occurred among people who began coloring their hair in the ’70s, before manufacturers stopped using carcinogenic compounds. Still, researchers are associating a rise in skin allergies to paraphenylenediamine (PPD), a chemical in more than two-thirds of permanent hair dyes.