Avobenzone

Avobenzone is an oil-soluble ingredient used in sunscreen products to absorb the full spectrum of UVA rays.

Uses

It is one of the few sunscreens, along with titanium oxide, zinc oxide and Mexoryl SX, that offers full spectrum UVA protection against sun damage.
In addition to being an active ingredient in sunblock formulas, avobenzone can also be found in other skin and body care products, including hand creams, moisturizers, and makeup foundations.

An oil soluble sunscreen agent. Classified as a “chemical” sunscreen because it works by absorbing UV rays over a wide wavelength, and then converting them to less damaging infrared radiation (heat). It’s marketed as a “broad spectrum” sunscreen because of it protects the skin against the sun’s entire range of UVA rays. It is one of the few chemical sunscreen agents with comprehensive UV protection, and for this reason, used in a large majority on sun protection products. It is also used in cosmetic products to protect other ingredients from deteriorating under the sun.
Tests have revealed avobenzone’s tendency to significantly degrade in light over time, lessening its sun protection capabilities. For this reason, most sunscreens containing the ingredient also include photo-stabilizing ingredients like octocrylene. A number of companies have developed technologies to help stabilize the ingredient (i.e. Helioplex™, Active Photo Barrier Complex™), however the full risks associated with long term use of avobenzone have yet to be determined.

Avobenzone appears to be relatively non-toxic and non-irritating to the skin. However, because it is often used in conjunction with photo-stabilizers, there is a greater risk for skin irritation and low-level toxicity.
Furthermore, some studies have demonstrated it to be absorbed by the body and secreted into urine, and is therefore not recommended to use on children or pregnant women. Some skin specialists believe it to be just as harmful as PABA, and certain studies suggest that the ingredient behaves similarly to the hormone estrogen;

If you are using this product under your doctor’s direction, your doctor or pharmacist may already be aware of possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor or pharmacist first.

butylmethoxydibenzoylmethane; 4-tert-butyl-4′-methoxydibenzoylmethane