Denmark restricts butylparaben in products for use by children younger than the age of three.

Butylparaben has not escaped controversy, which itself is controversial.

Butylparaben can also be found in the sewage.

Butylparaben is one of the most common bactericidal/fungicidal additives in cosmetics.

Butylparaben is weakly estrogenic, meaning it mimics natural estrogen in the body.

Butylparaben has been found in small concentrations in human breast fat and breast tumors.

The effectiveness of the parabens is usually enhanced when they are used in combination (e.g. butylparaben, ethylparaben).

The FDA says the most common are methylparaben, propylparaben and butylparaben.

Paraben esters, such as butylparaben, have been found to mimic androgen antagonist activity.

Butylparaben is not listed as a carcinogen by the International Agency for Research on Cancer.

Three popular products, produced under the leading brand Olay, contain a cosmetic preservative, butylparaben, that was tested on animals.

These include benzylparaben, butylparaben, methylparaben, and propylparaben.

Paraben, methylparaben, butylparaben and propylparaben - Used as preservatives, parabens are reported to interfere with male reproductive functions.

Since it can be concluded that the estrogenic activity of butylparaben is negligible under normal use, the same should be concluded for shorter analogs.

Rats exposed to a high concentration of butylparaben during pregnancy gave birth to fewer pups, and pups with malformed reproductive organs.

A scientific review found that butylparaben displayed the most competitive binding to rat estrogen receptors when tested along with methyl, ethyl, and propylparabens.

Butylparaben is prepared by the esterification of 4-hydroxybenzoic acid with 1-butanol in the presence of an acid catalyst such as sulfuric acid.

Butylparaben can also be found in low concentrations in liquid and solid medication suspensions, such as tylenol (acetaminophen) and ibuprofen.

Long-chained parabens, like butylparaben, are more estrogenic than short-chained parabens, like methyl- or ethylparaben.

It has been shown that butylparaben has the ability to cross body barriers, and enter the body through the lungs, GI tract, and skin epithelium.

The allergic reactions can be stimulated by any of the components of mascara but is usually attributed to methylparaben, aluminum powder, ceteareth-20, butylparaben, or benzyl alcohol.

Mice administered butylparaben at 0.01-1% body weight for ten weeks showed a decrease in serum testosterone concentration and in spermatid counts in the seminiferous tubules.

Oral administration of butylparaben to eight-week-old rats has caused tumors such as thymic lymphoma, non-thymic lyphoid leukemia, and myeloid leukemia.