The dark chromium oxide thus slowly replaces and covers the yellow color of the
lead chromate, causing the bright yellow areas in paintings to turn dark brown.
3 and 4 suggest that the CY yellow coating surface is much rougher than the rest, the presence of Pb originating from the
lead chromate yellow pigment is very likely due to the exposure of the pigment particles.
Working with C3H/10T1/2 cells, Patierno et al (12) showed that only particulate
lead chromate could induce neoplastic transformation while soluble sodium chromate could not.
Wide range of inorganic pigments include ultramarine blue,
lead chromates, chrome oxide, iron oxide, pearlescents, phosphoroescents, luminescents, cadmium, mixed metal oxides, titanium dioxide and predispersed flush pigments.
The two committees concluded that the alternatives to the pigments, mainly comprising inorganic pigments such as bismuth vanadate and organic pigments like azo diarylides, could not achieve the same levels of technical performance as the
lead chromates.
These include chemicals such as triglycidyl isocyanurate (TGIC), tri-mellitic anhydride (TMA) and
lead chromate based pigments.
Also reported were asbestos in roof patching or cement, benzene (pure form) for drying leather, benzene in gasoline/fuel or in cleaners,
lead chromate in paint for maintenance and in glazes for an art class, and sodium dichromate in floorstripper.
Cadmium pigments are not toxicologically the same as cadmium," he says, "and
lead chromate pigments are not toxicologically the same as lead.
For a small volume of products,
lead chromate was used to make bright colored products with excellent UV resistance.
The British Coatings Federation (BCF) warned that EU authorization of
lead chromate paints would perpetuate a global trade in
lead chromate pigments, including in countries with weak regulations.
Last, the new HEUCO[R]FIT LR pigment preparation line is designed to offer high-quality color solutions for
lead chromate replacement.
BASF is going to stop producing
lead chromate pigments by the end of 2014 at the latest, and concentrate worldwide; on the production and marketing of alternative products.
