A hundred years ago, fewer than half of all Americans brushed their teeth on a regular basis. Deodorant wasn’t really a thing until the 1950s. So when you think about all the stuff we spray, swab, slather, and smear on ourselves nowadays, you’ve got to wonder whether all those cosmetic chemicals are safe.

Unfortunately, there’s evidence suggesting many of them may not be, and a dearth of good long-term data to assuage the fears of experts who study these chemicals. The really scary part: Regulators assume a chemical is safe for use until proven otherwise. Think of it as a presumption of innocence—like the one federal health authorities granted cigarettes long after it was clear smoking was a noxious habit.

Here are the commonly used chemicals that should have you concerned, and how to avoid them.

These petroleum-based chemicals are a big hit among lotion and cosmetic manufacturers because they make things spread on evenly without caking or clumping. They also help keep fragrance molecules evenly distributed, which is why you don’t have to shake your cologne bottle before spritzing yourself. Research from Harvard University finds phthalates can mess with a man’s sperm. More research links the chemical to the kind of DNA damage that drives cancer.

This class of chemical is a preservative often added to shampoos, moisturizers, antiperspirant, and shaving products. Some studies indicate parabens have “estrogenic” properties, which may trigger or hurry the growth of cancer cells or tumors. They may also promote skin damage when used in—of all things— sunscreens, shows research from Food and Chemical Toxicology.

The amounts and interactions of the hormones in your body achieve a “delicate balance” to ensure you stay fit, disease free, capable of reproduction, and generally in good mental and physical health, according to a study from the journal Neuroendocrinology. But EDCs may mess with that balance. From hurting your ability to reproduce to raising your risk for obesity and many forms of cancer, the threats the study authors associate with EDCs are (for now) unsubstantiated … but super freaky. (Both parabens and phthalates are EDCs. But this category includes so many other potentially harmful chemicals that it would take an encyclopedia to list each one.)

Thanks to copyright laws and other regulatory safeguards designed to protect trade secrets first and consumer health second, you won’t find mention of a lot of these chemicals on a product’s label. In many cases, you’ll just see the word “fragrance,” which could include any combination of hundreds of substances.

To help you identify all the stuff in your grooming products, the Environmental Working Group’s Skin Deep database is a great resource. But really, your best bet is to ditch anything that isn’t essential. In particular, research suggests fragranced and spray-on products are likely the most harmful because of the chemicals they tend to contain and the risk of inadvertent inhalation. If you can buy unscented products, experts say that’s a good defensive maneuver.

Think of it this way: A nice smelling cologne or aftershave, fine. Washing up with heavily scented shampoo and soap, followed by aftershave, hair spray, antiperspirant, skin lotion, body spray, and a finishing mist of cologne… overkill, and maybe not just figuratively. Hopefully all of these chemicals turn out to be benign. But do you want to play guinea pig for your grandkids’ generation?