If you would like to learn more about the safety rankings used on our site, or the safety rankings of other personal care products on the market, visit the EWG Skin Deep Cosmetic Database.

You can also visit CosIng, the European Commission database of cosmetic ingredients, to learn about ingredients banned and restricted in the European Union. Below are terms to help you navigate the world of personal care product ingredients:

Anti-Static Agent - Substances that prevent or inhibit the accumulation of static electricity.

Antimicrobial - Substances that kill or control growth of living organisms.

Antioxidant - Substances that act as preservatives by inhibiting the oxidation process.

Binder - Substances used to hold ingredients together and give weight to a product containing small amounts of active ingredients.

Biocide - Substances or microorganisms that kill or control growth of living organisms. A biocide can be an antimicrobial agent.

Bulking Agent - Non-reactive additives that increases the volume or weight of a product, but contribute little or no nutritional value.

Cleansing Agent - Substances that clean skin and hair by helping to mix water with dirt and soil so that they can be rinsed away.

Chelating Agent - Substances that rearrange the chemical composition of heavy metals to improve the likelihood of them bonding with other ingredients.

Carcinogen  - Substances capable of causing cancer.

Cleansing Agent - Substances that remove dirt, buildup and odors.

Colorant - Substances that transmit color to a product.

Diluent - Agents used to dilute or thin substances with high viscosity.

Emulsifier - Substances used to mix components together that would normally repel each other.

Emollient - Conditioning agents that act as moisturizers to soothe and soften skin and hair.

Essential Oil - Oils obtained by the distillation of plants.

Extract - Substances drawn out of raw materials by a solution, heat or chemical process.

Film Former - Substances that dry to form a thin film on the hair, skin or nails.

Foam Booster - Substances that stabilize foams or increase a product's ability to foam.

Fragrance - Substances that transmit smell to a product. Fragrances are protected by U.S. trade secret laws, and therefore contents can remain undisclosed.

Hair Conditioning Agent - Substances that improve the feel, texture and shine of hair.

Humectant - Conditioning agents that slow the loss of moisture from a product by attracting and binding water.

Masking Agent - Substances that hide odors without reducing the general effectiveness of a product.

Occlusive Agent - Skin Conditioning substances that form a barrier on the skin's surface to slow the loss of moisture.

Opacifying Agent - Substances that reduce the transparency of a liquid.

Plasticizer - Substances that soften polymers to reduce brittleness and cracking.

Preservative - Substances that prevent or delay bacterial growth in order to protect a product from spoiling.

Skin Conditioning Agent - Substances including emollients, humectants and occlusive agents that lubricate and moisturize the skin to improve softness and the appearance of dry or damaged skin.

Solvent - Liquid or gas substances used to dissolve other substances.

Surfactant - Substances that decrease surface tension and help dissolve ingredients that would normally repel each other. Also called a surface active agent, surfactants can be cleansing agents, emulsifiers and foam boosters.

Stabilizer - Substances used to keep a product from separating or layering.

Thickener - Substance that can increase the viscosity of a liquid without reducing the general effectiveness of a product.

UV Absorber - Substances that preserve a product from deterioration by scattering, absorbing and reflecting UV light.

UV Filter - Substances that protect hair and skin from UV light by filtering it to a lesser degree.

Viscosity Increasing/Decreasing Agent - Substances that can increase or decrease the viscosity, or stickiness and thickness, of a product.