Europe
professional painters or industrial users.
Within coatings production plants,
companies would almost certainly have
to take mandatory precautions to protect
workers from the newly perceived dangers of TiO2 which would raise manufacturing costs.
However, the biggest long term impact
would come from TiO2 being automatically classed as a substance of very high
concern (SVHC) under REACH because
of its being carcinogenic.
This would raise doubts about the
commercial viability of products containing TiO2 – not only coatings, but also
inks, plastics and sunscreen protectors.
End users, particularly consumer brand
owners and retail chain, are treating
SVHCs with extreme caution, in some
cases blacklisting them.
The main objective behind the creation
of the SVHC category is that chemicals
within it will have to be authorized by the
European Commission on the recommendation of ECHA to be marketed within
the EU. Ultimately SVHC substances
would be replaced by safer alternatives.
Another major threat is that substances with TiO2’s similar potentially dangerous properties of having particles which
once inhaled can be hazardous because of
their low solubility or insolubility will be
given an identical classification. These
will also be given the SVHC tag and be
destined for authorization.
“TiO2 is not the only substance with
these levels of low solubility or insolubil-
ity,” explained Anthony Jones, chairman of
the Titanium Dioxide Industry Consortium
(TDIC), a sister organization of the Brussels-
based Titanium Dioxide Manufacturers
Association (TDMA). “Other chemicals
with similar properties include calcium car-
bonate, silicas and carbon black.”
The French proposal to ECHA argues
that TiO2 should be classified as a car-
cinogen 1b ( figure ‘1’ and letter ‘b’) or a
substance presumed to have carcinogenic
potential for humans.
In a report on the proposal, France’s
Agency for Food, Environmental and
Occupational Health & Safety (ANSES)
cites evidence from the Paris-based
International Agency for Research on
TiO2 as a substance “possibly carcino-
genic to humans.”
The data from two animal studies
conducted in the 1980s demonstrated
that TiO2 can cause malignant tumors in
rats following exposure by inhalation, ac-
cording to ANSES.
“Because of its physico-chemical
properties, exposure to titanium dioxide by the respiratory route, at a certain
level of concentration, may cause lung
overload and lead to an inflammatory
reaction, responsible for proliferative lesions,” said the agency, whose proposals
covers TiO2 in all its crystalline phases
and combinations of phases, sizes and
shapes of particles.
Under ECHA’s procedure for dealing
with cases for classification and labeling harmonization, the French proposal
has been put out for public consultation.
Then ECHA’s risk assessment committee
(RAC) has 18 months or before the end
of 2017 to make a recommendation to
the European Commission.
The RAC, comprising experts from
the EU’s member states on toxicology, has
to determine only whether the chemical is
inherently hazardous not the degree of its
risk or level of exposure.
There are a number of points which indicate that the committee is likely to come
out against classification of TiO2 which is
currently considered to be a relatively safe
chemical throughout the world.
First, the studies carried out in the
1980s on rats involved a high ‘overload’
dosage of TiO2 – 250 milligrams per cubic meter which was 25 times the occupational exposure limit in Europe.
Since then the Organisation
for Economic Co-operation and
Development (OECD), the Paris-based
agency for the world’s rich countries,
has drawn up guidelines on animal test-
ing limiting doses to 25-50 mg per cubic
meter. ECHA uses OECD guidelines as
criteria in its assessments of data so it is
unlikely to go against a guideline from
the organization on this occasion.
“In fact the studies included data from
dosages below and within these guideline
limits and the one at 250 mg was the only
one which resulted in the formation of tumors,” said Jones.
“Furthermore, the effects were very
much rat specific,” he continued. “Similar
tests have been done on mice and hamsters
without carcinogenic effects. Rats have a
different response mechanism. These tests
with rats cannot be applied to humans.”
The TDMA has also been collecting
epidemiological evidence verifying the
safety of TiO2 through exposure data.
This cannot be considered by RAC be-
cause it is not relevant to the issue of
TiO2 being inherently hazardous.
But in what will be a highly controversial matter if RAC supports classification of
TiO2, socio-economic issues may have to be
considered by the European Commission
before it takes the final decision.
“Epidemiological studies of over
20,000 workers exposed to TiO2 for several decades shows no evidence of occupational cancer, which is something that
hopefully will be taken into account,”
said Robinson.
The key factor dictating the final decision will be the futures of not only the
coatings industry but all the other sectors
using TiO2, as well as those applying substances with the similar bio-persistent properties of low or non-existent solubility. CW
“This is an initiative whose results could
be drastic.” – Janice Robinson, product
regulations director, at CEPE, Europe’s main
coatings trade association.
