Survey of Chemical Substances in Consumer Products, No. 81 2007 – Survey of nanotcnological consumer products

Survey of nanotcnological consumer products

Conclusions

These years, the industrialized countries invest heavily in nanotechnology and consequently the area is progressing with great speed. Almost every day new industrial prospects are presented in this area. However, as the nanotechnological products are increasingly developed for the consumer market, the Danish Environmental Protection Agency (DEPA) tendered a “Survey of products which contain nanoparticles or which are based on nanotechnology”. The present survey was performed by DHI – Institute for Water and Environment (DHI) in cooperation with Institute for Environment and Resources of DTU.

Survey of actors and consumer products

The primary source of information was interviews and questionnaires to the actors in Denmark, internet searches and follow-up on search results of consumer products in an American database (’A Nanotechnology Consumer Products Inventory’ called the Woodrow Wilson database). Focus were only to consumer products where the user is exposed to nanotechnology by general use, e.g. are electronic products with nanotechnologically produced memory chips deep inside the product not included, whereas tennis rackets and golf balls with nanotechnologically treated surfaces are.

Typically, the consulted trade associations in Denmark do not have information on their member’s nanoproducts and they report that until now the activity with respect to production, formulation or import of consumer products containing nanomaterials seem to be limited. An exception is the Association of Danish Cosmetics, Toiletries, Soap and Detergent Industries (SPT), which has already treated nanotechnology on their meetings and mini conferences. On these meetings the foucs was on assessment of possible health effects. However, the associations report an increasing number of inquiries about possibilities and regulations of nanotechnology.

The primary Danish actors are a number of Danish companies with net shops, specializing in products for surface treatment for industry and consumers and a number of producers and suppliers of cosmetics whose brands are found in the retail trade. Generally, distributors of branded goods, for example sports clothes and electronics may also market articles containing nanotechnology.

The survey is based on direct contact to the supply chain and publicly available information such as advertisments, web pages, brochures etc. There is no legal requirement to producers or importers of products to declare the content of nanomaterials. Therefore, it is not possbile to be certain that a producer or importer who uses the prefix ‘nano’ in association with a product are referring to a content of nanoparticles, a nanometer thin surface layer of materials or whether it is the technology behind the product that is ‘nano’. The likelihood that ‘nano’ is used in advertisement without a background in real nanotechnology is assessed as minimal.

The survey found 243 products based on a nanomaterial on the Danish consumer market. The searches for Danish importers and distributors of products in the Woodrow Wilson database and Danish web shops selling these articles showed that generally two out of three products registered in the U.S.A. are for sale in Denmark.

There are products on the market containing nanomaterials, especially within surface treatment, cosmetics and sport equipment. Within the areas of surface treatment for cars and houses the Danish market is very dynamic and considerably more products are registered in Denmark than in the U.S.A.

More than two thirds of the products on the Danish market – 154 pcs. - are variuos liquid products partly for surface treatment of a great number of materials such as glass, concrete, metal (especially car maintenance) glass fibres and textiles and partly skin protection products, especially sun lotions. The remaining products are especially sporting goods- and clothing, which account for 60 out of the 99 remaining products. Here the nanomaterial is structurally encapsulated in the product, e.g. in golf balls or tennis rackets.

More than half of the consumer products on the Danish market are products from Europe. Out of the 135 European products on the Danish market, almost 100 come from Germany. The remaining originates in United Kingdom, Finland and France. Three products are sun lotions formulated in Denmark.

In 202 out of 243 products it was not possible to identify the nanomaterial in the product. Of the 41 known nanomaterials, half of them were found in cosmetics products (six products with zinc oxide and 13 with titanium dioxide), 10 with antibacterial silver in textiles and home appliances, and 12 with carbon tubes or balls (seven with carbon tubes in sporting goods and five with fullerenes in cosmetics).

Titanium dioxide was assessed by the European Commission’s Scientific Committee on Consumer Products (SCCP) to be safe for consumers when used in sunscreens in concentrations up to 25% regardless of the particle size. Zinc oxide is accepted for use as a colouring agent, but it is not allowed for use as a UV filter in cosmetic products. Silver as a biocide is under risk assessment in the EU. It is assumed that fullerenes are imported with products formulated outside the EU.

A considerable part of the consumer products are sold in web shops in Denmark and abroad, especially products for surface treatment within the product types `Car accessories’, ‘Home and gardening’ and ‘Personal care and sports equipment’, but a smaller increasing part are found in street shops.

Paints are particular products in relation to nanomaterials. In certain black paints ‘carbon black’ (20-100 nm) is applied as colouring agent, and in some paints the thickening agent silica is used in nano size (down to approx. 10 nm). Both these materials have been used for a number of years, but are only now recognized as nanomaterials. In the Danish Product Register a great number of individual products are registered with carbon black (approx. 9,500) or silicium dioxide (approx. 15,500). It cannot be established how many of the products actually contain nanomaterials since it is not registered whether the substances occur as larger particle, nanosized particles, in liquid or solid form. The registered amounts used in paints are 483 tons carbon black and 622 tons silicium dioxide. The individual products containing these materials have not been further analysed.

Consumer exposure to products containing nanomaterials

A risk assessment of nanomaterials in consumer products would normally be based on a hazard assessment of the relevant nano-sized chemical substances in the products, and the first challenge here would be to identify the chemical substances found in the products and their concentration. This information is available from the producer, but the information of the chemical substance and the characteristics of it are confidential. Therefore, information of the composition of the specific surveyed products could not be obtained.

If the identity of the nano-sized chemical substances was known, the next challenge would be to identify toxicological effects of the substances. There are very few available data on nanomaterials, and the toxicity of nanoparticles may depend on e.g. the surface area of the substance rather than on the dose.

Due to this and to prioritize the efforts made with certain types of products, an assessment of the exposure potential for the surveyed products has been developed.

Since the exposure scenarios are based on the available information they are somewhat theoretical. It is not possible to estimate a risk associated with the use of the products since it may not be known whether nanosized substances are in fact absorbed in humans. Regarding sunscreens titanium dioxide has been used for a number of years. The European Commission’s Scientific Committee on Consumer Products has assessed the use to be safe for consumers.

The nanomaterial in most products on the Danish market is found in the category ‘Nanoparticles suspended in liquids’ that comprises the many products for surface treatment. The remaining products are categorized as ‘Nanoparticles encapsulated in solid materials’, ‘Film in nanometre thickness’, ‘Surface-bound nanoparticles’ and ‘Nanostructured film’, where the nanomaterial is often encapsulated in or bound to the surface. No consumer products containing nanomaterials in free form have been found.

An assessment shows that the risk of exposure to the consumers is greatest from products of the category ‘Nanoparticles suspended in liquids’, because it is a liquid product for e.g. surface treatment or cosmetic application to the skin. Products in spray form must be expected to cause exposure both by inhalation and by dermal contact – however, only a few spray products were found (with pumps, not with gas propellants).

According to the actors of the market, nanomaterials do no appear in the products in concentrations demanding labelling or classification. Thus, there is no available information on the active nano material in the products. Safety data sheets on the remaining ingredients of the products can often be provided as well as a producer declaration about the general characteristics of the nanomaterial.