Cadmium in artists' paint

Kristin Fyrand <kristin [at] konservering__se> writes

>The following is posted on behalf of The Swedish Chemicals Agency:
>
>Questions on Cadmium in artist paint - Proposal for an EU-wide
>restriction
>
>Sweden (The Swedish Chemicals Agency) is doing preparatory work on a
>proposal for an EU wide restriction under REACH for Cadmium and
>cadmium compounds in artist paint and pigments for enamel, ceramics
>and glasses. Thus it is important for us to collect as much relevant
>information as possible from stakeholders.
>
>    Do you use alternative pigments for substitution of cadmium
>    pigments in artist paints (and for cadmium pigments used in
>    enamels, ceramic and glasses)?
>
>        If not, why?
>
>        If there are areas where use of cadmium based artist paints
>        are required, what is the reason for the need?
>
>        If you use alternative pigments, to what extent?
>
>    Which alternative chemical substances are available and most
>    common for substitution of cadmium pigments in artist paints
>    (and for cadmium pigments used in enamels, ceramic and glasses)?
>
>    Are there any technical differences between the uses of cadmium
>    pigment based paint compared to alternative pigments?
>
>        If so, what are the differences?

Cadmium sulfides, cadmium selenosulfides, cadmium zinc sulfides,
cadmium sulfides laked on barium sulfate, and cadmium mercury
sulfide with, and without, barium sulfate, are common pigments world
wide in the yellow orange and red range.  They are a lot more stable
than the organic pigments that replace them.

And every country I know, has exempted art materials from the
environmental regulations and from consumer lead and cadmium
regulations. Worse, paint and pigment manufacturers have obtained
exemptions for the benzidine pigments such as benzidine yellows that
are substitutes for cadmium.  While almost every country bans the
use of the cancer-causing benzidine dyes, these benzidine pigments,
which are only less soluble in water/acid, are exempt.  The acid
solubility test used by art materials manufacturers to show these
pigments are "safe" has been shown not to relate to bioavailability
in humans.  It is clear we have many digestive and uptake mechanisms
other than stomach acid such as enzymes, heat, cellular activity,
alkalis, bacteria, and more.

In other words, to ban cadmium and let them replace it with
benzidine pigments is to go from the fry pan to the fire.

And why start with cadmium?  I think it might be easier to set a
precedent by banning mercury containing pigments first.  They are
pretty stable in the environment, but mercuric sulfide (Vermillion)
and cadmium mercury sulfide, are still in use.

Or how about the arsenic paint pigments which are only available now
from a few places, but which are common in opaque white or pastel
glass and enamel colors.  Arsenic in glass can be replaced by
fluoride minerals.

At this point, I would be happy if the makers would provide precise
chemical labeling so people could make up their own minds.  And in
the US, I want the "nontoxic" label removed from all adult artists
paints because the manufacturers are assuming there is no exposure
to the toxic pigments if the paints are used as directed.  And how
dare they call the majority of the organic pigments "nontoxic" when
there is no chronic data on them?  It is such an outrage. And the
public is completely misled by this word.

As for children's art materials, what gives Crayola, Prang and all
the other manufacturers the right to consider those pigments "trade
secrets?" A mother will find it absolutely impossible to identify
the pigments in any child's product in the US and probably
elsewhere.  Those pigments are sure as hell not FDA batch-approved
food dyes and pigments.  And even if they were, some mothers need to
know this.  I don't know about you, but if it weren't for crayons,
I'd have gone hungry as a child.

Cadmium can really be easily replaced in glazes, enamels and glass.
There are many other metals and mixtures of metals that will work.
But remember that in these fired products, there must be *metal*
pigments because organics would burn off.  So you are limited.  Many
toxic minerals are used including many of the rare earth metals
about which there is almost no toxicity data.  Even uranium is still
used in some glasses. Many colors and techniques will depend on the
use of lead as a flux and major ingredient.

I inspect college art facilities and see the messy areas in which
glass is cut and ground with the fine mist and dust drying to a
powder everywhere. I see the mixing of powdered glaze chemicals out
in the open rather than in a fume hood or ventilation system.  I see
airbrushing of paints without ventilation, sanding of canvas paints,
and other outrageous practices.  It is not only the toxic substances
in art materials.  It is massive ignorance and abysmal 19th century
conditions under which art is taught at the college level that are
at fault.

I've jumped around in this post. so I'll summarize the points I'm
trying to make.

    The art materials industry/pigment manufacturers are a strong
    industry and have exemptions worldwide that will be difficult to
    repeal.

    Cadmium is one of the more widely used colors and it might make
    more sense to start with less common pigments containing mercury
    and arsenic.

    There should be some kind of consumer label provisions to alert
    users to the presence of toxic replacements for the metals that
    are banned.

I don't think trying to ban the cadmium from all these art materials
will work.  But if there is *anything* I can do to help you try, I
certainly will.  I have never thought that art has the right to take
casualties.

Monona Rossol, MS, MFA, Industrial Hygienist
Arts, Crafts and Theater Safety, Inc.
181 Thompson St., #23
New York, NY 10012-2586
212-777-0062


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                  Conservation DistList Instance 27:6
                  Distributed: Saturday, July 20, 2013
                        Message Id: cdl-27-6-003
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