Heavy Metals Analysis in Cosmetics
By Impact Analytical
Testing of Cosmetics for Heavy Metal Content
Throughout the growth of the cosmetics industry, consumers have begun to question “heavy metals” appearing in cosmetics. The term heavy metal refers to any metallic chemical element that has a relatively high density and is toxic or poisonous at low concentrations. A few heavy metals that are naturally present in the earth include: arsenic, cadmium, chromium, cobalt, lead, mercury and nickel. Due to cosmetics being in direct contact with the skin, heavy metals present in them become concentrated and enter human tissues. The heavy metals then can bind to and interfere with the functioning of organs and body systems, becoming toxic. The World Health Organization (WHO) has produced a list of ten chemicals of major public concern. The heavy metals mentioned above all appear on this list. Heavy metals have potentially toxic effects depending on several factors. These factors include the exposure condition (inhalation or skin contact), exposure frequency, exposure length, and the amount of exposure.
The U.S. Food and Drug Administration (FDA) addresses the following limits for heavy metals in cosmetics within regulations and guidance documents:
Utilizing the technique of Inductively Coupled Plasma (ICP) Spectrometry, the amount of heavy metals in a material can be determined. ICP Spectrometry techniques have the capabilities to identify and quantify trace metals at percentage levels as well as at the parts per million, parts per billion, and parts per billion levels by using established sample preparation techniques and analyses. Varying digestion techniques, including aqua regia, hydrofluoric acid (HF), as well as hot plate and microwave digestion allow Impact Analytical to analyze nearly any product for heavy metals. Impact is then able to determine the Limit of Detection (LOD) and Limit of Quantitation (LOQ). As cosmetic matrices are widely various (solid, solution, gel, lotion, paste, etc.), sample preparation and LOD/LOQ can vary from product to product.
The United States Pharmacopeia (USP) has issued a general chapter <232> for the analysis of elemental impurities in drug products. These impurities are classified into separate groupings based upon their risk of exposure (due to components – either excipients or drug substances, manufacturing process, or route of exposure). Although the United States FDA does not have recommended limits for the content of these heavy metal elements in cosmetics, it may be useful to analyze for confirmation of product ingredients as well as full transparency. The labs at Impact Analytical have the full capabilities to analyze for all these heavy metals in a wide array of products.