What Are Phthalates?

Phthalates (pronounced "THAL-ates") are a group of synthetic chemicals used primarily to make plastics flexible and to help fragrances last longer. They appear in a wide range of consumer products — from vinyl flooring and shower curtains to perfumes, lotions, shampoos, nail polish, and food packaging. They are one of the most pervasive endocrine-disrupting chemicals in the modern environment, and virtually every person tested in population-level studies shows detectable levels of phthalate metabolites in their urine.

Why It Matters

Phthalates are classified as anti-androgenic endocrine disruptors, meaning they interfere with the function of male hormones (androgens like testosterone). Research has linked phthalate exposure to reproductive issues in males, including reduced sperm quality, altered genital development in boys (a condition researchers call "phthalate syndrome"), and decreased testosterone levels. Effects have also been observed in females, including early puberty and reproductive health concerns.

What makes phthalates particularly concerning is the combination of their endocrine-disrupting properties and their ubiquity. They are in your shampoo, your vinyl flooring, your takeout container, your child's toys, your car's dashboard, and the fragranced candle on your table. Because exposure comes from dozens of sources simultaneously, cumulative exposure is significantly higher than any single product would suggest.

The regulatory response has been uneven. The EU and Canada have restricted several phthalates in cosmetics, toys, and food contact materials. The U.S. has been slower to act, though the Consumer Product Safety Commission has permanently banned several phthalates in children's toys.

How It Works

Two main categories of phthalates appear in consumer products:

Low-molecular-weight phthalates (like DEP — diethyl phthalate) are used in personal care products as fragrance solvents. DEP helps fragrances last longer on skin and in products. It appears on ingredient labels as part of "fragrance" or "parfum" and is rarely listed by name. This is the primary phthalate of concern in cosmetics and personal care.

High-molecular-weight phthalates (like DEHP, DINP, DBP) are used as plasticizers to make rigid plastics soft and flexible. They are found in PVC (vinyl) products, food packaging, medical devices, and building materials. DEHP in particular has been linked to the most serious health concerns.

Exposure routes: Phthalates enter the body through skin absorption (from personal care products and contact with soft plastics), inhalation (from fragranced products and off-gassing of vinyl), and ingestion (from food contact with phthalate-containing packaging). The body metabolizes phthalates relatively quickly — within hours to days — but daily exposure from multiple sources maintains constant levels.

Health research: The most robust evidence links phthalate exposure to male reproductive effects. A seminal study by Dr. Shanna Swan found that higher prenatal phthalate exposure correlated with shorter anogenital distance in male infants — a marker of impaired masculinization also seen in animal studies. Subsequent research has connected phthalate exposure to reduced sperm count, lower testosterone, altered thyroid function, and neurobehavioral effects in children.

What to Watch Out For

• "Fragrance" on a label almost always contains phthalates. Unless a product specifically states "phthalate-free" or discloses all fragrance components, assume that "fragrance" or "parfum" on the ingredient list includes phthalate solvents. This is the single biggest source of phthalate exposure from personal care products.
• Vinyl products off-gas phthalates. That "new car smell" or "shower curtain smell" is partly phthalates volatilizing from vinyl. Choose PVC-free alternatives for shower curtains, flooring, and children's products when possible.
• Microwaving food in plastic increases phthalate migration. Heat accelerates the leaching of phthalates from plastic containers into food. Use glass or ceramic containers for heating food, even if the plastic is labeled "microwave safe."
• Recycling code 3 (PVC) indicates phthalates. Look for the recycling number on plastic products. Number 3 is PVC, which typically contains phthalate plasticizers.

The Bottom Line

Phthalates are among the most well-studied endocrine disruptors, with strong evidence linking them to reproductive and developmental effects, particularly in males. The most practical steps to reduce exposure are choosing fragrance-free personal care products (or products with fully disclosed fragrance ingredients), avoiding PVC/vinyl products, not heating food in plastic, and selecting phthalate-free products where available. These changes will not eliminate exposure entirely, but they can substantially reduce it.

Frequently Asked Questions

Are all phthalates equally harmful?

No. Different phthalates have different potencies and health profiles. DEHP and DBP are among the most studied and concerning, and both have been restricted in children's products in the U.S. DEP (the one most common in personal care products) is considered less potent but is also less studied for long-term effects. The concern with DEP is primarily the cumulative exposure from daily use of fragranced products.

How can I tell if a product contains phthalates?

It is difficult because phthalates are hidden within the umbrella term "fragrance." If an ingredient list says "fragrance" or "parfum" without further disclosure, phthalates may be present. Look for products labeled "phthalate-free" or that fully disclose their fragrance ingredients. You can also check EWG's Skin Deep database for product-level ingredient information.

Are phthalates in food?

Yes. Phthalates can migrate into food from processing equipment, packaging, and food-contact gloves. Studies have found higher phthalate levels in people who eat more processed, packaged, and restaurant food compared to those who eat primarily home-cooked meals from fresh ingredients. Reducing packaged food consumption and using non-plastic food storage can lower dietary exposure.