In beauty, heavy metals usually show up as trace impurities in color pigments (think lipstick, eyeshadow), not always as an intentionally added ingredient. The concern is that metals like lead can be harmful with enough exposure over time, so many people prefer to minimize them where possible. The tricky part: they often won’t be listed on the label. To reduce risk, stick with reputable brands, avoid sketchy/imported products with no transparency, and be extra picky with very cheap, highly pigmented makeup. Watch for red-flag ingredients like lead acetate (a direct lead compound).

“Fragrance” (or parfum) is used to make products smell good and cover up the natural scent of ingredients. The reason it shows up on low-tox lists is simple: companies can list “fragrance” as one ingredient without telling you what’s actually inside that scent blend, because the specific components are often treated as proprietary. That means if you’re trying to avoid certain ingredients (or you’re sensitive/reactive), fragrance can be a blind spot. To spot it, look for fragrance, parfum, aroma, perfum(e), and even certain essential oil blends if you’re sensitive. If you want to avoid the mystery, choose fragrance-free (not just “unscented”) or brands that fully disclose fragrance components.

Phthalates are often used to help fragrance last longer and can show up in scented lotions, perfumes, hair products, and sometimes nail products. People avoid them because some are linked in research to hormone-related effects, and “fragrance” can be a black box. The hard part is that phthalates may not be listed directly—because they can hide under “fragrance” or “parfum.” To spot them, look for DEP/DBP on labels, and if you want to avoid them, choose fragrance-free products (not just “unscented”).

These preservatives help prevent bacteria and mold in products that sit in warm bathrooms, but they can be irritating or sensitizing for some people—especially if you already deal with itchy scalp, rashes, or “mystery” skin reactions. Many low-tox shoppers avoid them as a simple troubleshooting move. To spot them, look for names like DMDM hydantoin, quaternium-15, imidazolidinyl urea, diazolidinyl urea, bronopol, or sodium hydroxymethylglycinate.

PEGs are used to make products feel smooth and creamy and help oil and water mix (common in cleansers, lotions, hair products). The concern is that some PEGs (and other “ethoxylated” ingredients) can be associated with manufacturing byproducts that people prefer to avoid. To spot them, look for PEG- followed by a number (like PEG-40), “polyethylene glycol,” and ingredient endings like -eth (for example, laureth, ceteareth).

BHT and BHA are preservatives/antioxidants that keep oils from going rancid and help products stay stable longer (often in makeup and lip products). Some people avoid them because they’re debated in safety conversations, and many prefer alternatives when they’re easy to find. The good news: they’re usually simple to spot—look for BHT, BHA, butylated hydroxytoluene, or butylated hydroxyanisole.

Siloxanes (silicones) are what give products that silky slip and “pore-blurring” feel—common in primers, foundations, hair serums, and some deodorants. Some people avoid certain types due to environmental concerns and/or because silicones can cause buildup for their hair or skin. To spot them, look for ingredients ending in -cone, -methicone, -siloxane, and names like cyclopentasiloxane or cyclotetrasiloxane.

These are chemical sunscreen filters used to absorb UV rays. Some people avoid them because of concerns around absorption, sensitivity, hormone disruption. To spot them, look for octinoxate (also called ethylhexyl methoxycinnamate/octyl methoxycinnamate) and oxybenzone (also called benzophenone-3). If you’re avoiding them, many people choose mineral sunscreens with zinc oxide or titanium dioxide instead.

Carbon black is a pigment used to make products black, especially mascara, eyeliner, and brow products. It’s on “ingredients to know” lists because of broader safety debates, and some people prefer to avoid it—especially in products that could be inhaled (like loose powders or sprays). To spot it, look for carbon black or CI 77266.

Benzophenone compounds are used to help protect formulas from light and keep products stable (they can show up in some cosmetics, fragrances, and personal care). Some low-tox shoppers avoid them because they’re debated and often not essential for how a product performs day-to-day. To spot them, look for benzophenone and related names like benzophenone-1, -2, -3, or words like sulisobenzone and dioxybenzone.