Most water-borne preservatives contain CrVI compounds, originally to reduce corrosion although now also to improve toxicant fixation. Chromium contributes to preservation and this is recognised in, for example, New Zealand and USA where chromium contents are included in calculations of overall preservative activity of CCA formulations, but chromium may also have anti-stain and joinery (millwork) primer functions. CrVI can represent health and environment risks but only if a preservative is carelessly handled; chromium is fixed in treated wood which does not present a risk. CrVI is essential for fixation in preservatives such as CCA formulations but the development of new preservative uses for chromium should be directed towards CrIII which is virtually nontoxic.
Keywords: CHROMIUM; HEALTH & SAFETY; ENVIRONMENT; CCA SALTS; CCA OXIDES; WATER-BORNE PRESERVATIVES; TRIOLITH; WOLMAN SALTS; CORROSION