Determination of Mercury Levels in Cosmetics Formulations; Mexico’s Case

Abstract: Mercury is considered one of the most toxic elements for plants and animals. Nevertheless, in the Middle East, Asia and Latin America, whitening creams containing mercury have been manufactured and purchased despite their confirmed health risks. Due to mass distribution, this can be considered a global public health issue. In Mexico, these products are widely available in pharmacies, beauty aid stores and health stores. They are primarily used by women for their skin lightening effects. Mercury salts inhibit melanin formation by competing with copper in tyrosinase. The aim of this work was to analyze the mercury content in some cosmetic whitening creams using the cold vapor technique coupled with atomic absorption spectrometry (CV-AAS). Preliminary studies were conducted in order to evaluate several digestion methods. The results showed that a mixture of HNO3 and H2O2 by microwave digestion provided a higher signal of mercury. A total of 16 skin-lightening creams from the local market were investigated. No warning information was noted on the packaging. In 10 of the samples, no mercury was detected. However, the mercury content of six of them varied between 780-36,000 parts per million (mg L), despite U.S. Food and Drug Administration (FDA) regulations that limit mercury to 1 ppm. Even so, skin creams containing mercury are still available and commonly used in Mexico and many developing countries and their contents are poorly controlled.