Ask the Expert Question-and-Answer Archive

by Ron Joseph

July, 2002

Chromium as a Paint Ingredient

Q. I am trying to find out whether chromium is (or has been used historically) as an ingredient/constituient in paint. The situation that we have is as follows: we have an old piece of equipment (dates back to the 1960's-early 1970's) that is made of metal and was painted. We are looking to dispose of this old machine and we had some paint chips tested (TCLP) and learned that chromium was present. What we are trying to figure out in order to properly dispose of this is whether the paint may have contained chromium as an ingredient or whether the chromium may have "leached" from the metal (equipment itself). We have seen other interesting ingredients used in making paint (including various other metals and even PCB's) and thought that chromium might also be a possibility. I would welcome any information that you may have on this issue.

A. Chromate containing (hexavalent chromium) pigments are still used in corrosion inhibitive primers, and it is quite possible that some of the chromium that you re seeing comes from the primer. Also, prior to the 1980s, many of the reds, yellow, oranges and derivatives of these colors, such as some greens, had a high lead-chromate content. In the 1980s, due to OSHA regulations, many of the colored paints, as listed above, were reformulated so as to exclude lead and chromate ingredients.