Trace metals / impurities

Even high-quality colorants might contain unwanted substances, which need to be identified and whose effect on the product’s properties has to be assessed. Once the substances’ profiles are clarified, appropriate measures will be taken in order to ensure the safe use of colorants.

Our current focus is on:

  • Heavy metals:
    Already in the ‘70s we issued the first recommendation on the content of heavy metals in colorants. These general limits have been incorporated in many regulatory texts and are still the reference, e.g., for textile applications. As latest example, the ZDHC MRSL also refers to these limits for heavy metals in pigments relevant for the apparel industry.
    More recently we issued recommendations for the metal content of pigments used in toys and food contact applications, and made the requirements for metals in dyes mandatory for all our members.
  • General impurities:
    The impurity profile of colorants is more and more important for modern standards and regulatory purposes. We constantly update our information on existing and newly identified impurities, update our own references for colorants accordingly, and provide external input to other involved parties.
  • PCBs (polychlorobiphenyls):
    We were the first to address the presence of PCBs in some organic pigments, to propose corresponding safe limits and a suitable analytical method.
  • PAAs (primary aromatic amines classified as carcinogenic):
    We recently “upgraded” our limits for PAAs in dyes in consumer applications to mandatory requirements for ETAD members, and finalized a specific method for PAAs traces in organic pigments. We also discuss with competent authorities new regulatory developments for PAAs in various applications.

Working together for safer colorants