As with the nonvinyl toys, leaded vintage PVC toys may contain the pigment lead chromate
. Figure 2 shows chromium content in vintage vinyl (open circles) as a function of lead content.
As they age, the small lead chromate
particles are completely reduced to chromium oxide, while larger ones maintain a core of lead chromate
that is coated in a shell of chromium oxide.
As all three coatings are formulated well below CPVC, the different surface features observed are primarily due to the pigment particle size (e.g., lead chromate
> iron oxide > titanium dioxide > phthalocyanine blue), as well as their concentration.
However, numerous studies investigating particulate Cr(VI) compounds such as calcium chromate, strontium chromate, lead chromate
and zinc chromate observed significant increases in lung tumours.
Inorganic yellow pigments based on bismuth provide heat stability requisite for engineering thermoplastics to replace lead chromates
. Polymer-soluble dyes for use in polyester, PS and acrylic.
The intake of lead chromate
, added as a colourant to chilli powder, results in epigastricpain, anaemia, nausea and constipation due to lead toxicity.
Lead compounds may be employed in the production of colored plastics (in which lead chromates
are used as pigment) and in the manufacture of polyvinyl chloride (PVC) plastics (in which 2%-5% lead salts [including lead oxides, phthalate, sulfate, or carbonate, depending on the desired quality of the final product] are used as stabilizers).
However, ECHA's two specialist committees dealing with authorizations--one covering health and environmental risks and the other socio-economic issues both recommended that the lead chromates
be authorized for 12 years with a review after seven years of data from health and environmental monitoring of the products.
are an example of a class of pigment which ECHA has labeled as a substance of very high concern (SVHC) on the grounds that they can be carcinogenic, mutagenic and toxic for reproduction (CMR).
The revision takes account of the reduced risk from powders as high toxicity ingredients such as triglycidal isocyanurate (TGIC) cross-linkers and lead chromate
pigments have now largely been removed from UK manufactured products.
They are used for the formulation of paints and coatings as an inorganic alternative to pigments containing lead chromate
Clariant's pigment ranges have been manufactured without lead chromate
for a long time.