Scientific uncertainty
Several studies suggest that some products containing nanomaterials may present risks to health and environment. It is in any case the conclusion of the French Agency for Environmental and Occupational Health Safety (Afsset), who just published the results of a collective expertise on risk assessment on nanomaterials for general population and the environment.
Afsset found several hundred consumer products containing nanomaterials (cosmetics, textiles, food, sports gear, construction materials), for which the agency notes "a context of scientific uncertainty".
The agency underlines that consumer exposure to manufactured nanomaterials and the environmental dispersion resulting from their consumption, prove "to be extremely complex to evaluate, both qualitatively and quantitatively", particularly because of the low traceability of nanomaterials in products intended for consumption. As for studies on risks to health and environment, they represent only 2% of published studies on nanomaterials, and are often affected by many biases (absent or incomplete characterization of nanomaterials, studies conducted on synthetic molecules not deriving from finished products, studies on far higher doses than actual exposure, etc..).
Sunscreens
In an attempt to better assess the extent of risks Afsset selected and analyzed four types of products incorporating nanoparticles: antibacterial socks (silver nanoparticles), self-cleaning cement, sunscreen (nanoparticles of titanium dioxide), and sugar powder (food nanosilice). These products are widely used and representative of different routes for direct exposure (dermal, by inhalation or by ingestion), but Afsset said that in this area, "findings of a study conducted on a specific case cannot in any case be generalized or extrapolated to another product in the same category".
Regarding sunscreens, the agency notes that if, until very recently, various studies showed that there was no passage of nanoparticles of titanium dioxide (TiO2) through the skin barrier, " results of some more recent studies show, on the contrary, the existence of a skin passage and the possibility for these TiO2 nanoparticles to be found in the deep layer of the epidermis".
nanosize titanium dioxide
Afsset considers that the risk to human health cannot be excluded for sunscreens containing TiO2, "given the uncertainties on the potential for skin penetration and phototoxic activity". With regard to ecotoxicity, no consistent data is really available.
A possible ban?
Given this uncertainty, on behalf of the precautionary principle, Afsset recommends acting without delay.
The agency thus recommends:
making nanomaterials traceability mandatory, which requires a compulsory declaration from the actors in the industry,
implementation of clear labelling mentioning the presence of nanomaterials in products and informing on the possibility of release during usage,
going as far as prohibiting certain uses of nanomaterials for which the usefulness is low compared to potential hazards, at a press conference, Martin Guespereau, Afsset’s Director for instance, declared he was in favor of banning antibacterial socks, given the potential risk and low social utility,
harmonizing French and European regulations to apply the best practices, especially with a revision of REACH in order to take into account specifically manufactured nanomaterials regardless of tonnage.
From this point of view, regulations concerning cosmetics anticipates several points. The new Regulation (EC) N° 1223/2009 of 30 November 2009 provides notification and assessment of the safety of cosmetic products containing nanomaterials (applicable from January first, 2013) and indication of nanomaterials in the list of ingredients.
Moreover, given the urgency to progress on the knowledge concerning exposures and potential hazards of nanomaterials, Afsset also makes recommendations for elaborating a revised approach on health risk assessment that is appropriate to nanomaterials specificities.
