Posted: March 6, 2008

Japan's goverment to evaluate safety of nanomaterials

(Nanowerk News) Japan's Ministry of Health, Lobour and Welfare held the first meeting of study groups on the safety of nanomaterials such as carbon nanotube and fullerene at a joint government building in Chiyoda Ward, Tokyo, March 3, 2008.
The study group will discuss the safety of nanomaterials and their effects on people's health. This meeting was jointly held as the first meeting of the respective "study group on measures to prevent workers from being exposed to chemicals, which are not confirmed as non-toxic to human" and "study group on nanomaterials' safety."
"The study group on measures to protect workers from exposure" and "the study group on nanomaterial safety" were set up by the director generals of Pharmaceutical and Food Safety Bureau and Labour Standards Bureau, the Ministry of Health, Labour, and Welfare, respectively.
The two study groups are planning to conduct discussions together for the first three meetings. Shoji Fukushima, director at the Japan Industrial Safety & Health Association and Japan Bioassay Research Center, has become the chairman of both study groups.
The study groups consist of 22 intellectuals from administrative research institutes such as the National Institute of Occupational Safety and Health, Japan, the National Institute of Advanced Industrial Science and Technology (AIST) and the National Institute for Materials Science (NIMS) as well as universities including Keio University and Kyorin University.
Among chemicals including nanomaterials, which have not necessarily been confirmed as non-toxic to human beings at this point, "the study group on measures to protect workers from exposure" will discuss measures to prevent workers from being exposed to nanomaterials, for which there is concern that they may damage human health, based on the results of animal experiments and other factors.
The study group's purposes are to discuss the assessment of health effects of target chemicals as well as issues concerning their impacts on workers on site and to consider necessary preventive measures for safety.
On the other hand, "the study group on nanomaterial safety" will discuss how to assess safety and what safety measures should be implemented amid the rapid advancement of nanotechnology applications and development, which has resulted in the possible health effects of nanomaterials uncertain.
What directly triggered the formation of these study groups was a notice regarding "preventive efforts to stop current exposure at work sites manufacturing and handling nanomaterials," which the director general of Labour Standards Bureau under the ministry issued to the director of the labour department in every prefecture on Feb 7, 2008.
In this notice, the bureau required efforts to seal manufacturing facilities, manage processes so workers are not exposed to nanomaterials and require that workers wear dust masks and other items to protect their breathing, for example. The term "workers" here represent people working at sites, where target substances are handled for repair and inspection in addition to manufacturing, and people engaged in manufacturing using target materials for the purpose of research and development.
A proposal request concerning "safety measures related to nanotube and other nanomaterials," which the director general of Tokyo Metropolitan Government's Bureau of Social Welfare and Public Health sent to director generals of Pharmaceutical and Food Safety Bureau and Labour Standards Bureau on Feb 22, 2008, also seems to have become one of the direct triggers behind the formation of the study groups.
Nanomaterials targeted in the discussions of these study groups are defined as materials in the forms of thin-film, sticks and particles, for example, with a one-dimensional length of less than 100nm, and they exhibit characteristics such as larger surface area and the emergence of quantum effects.
Specifically, more than 20 kinds of nanomaterials including fullerene, carbon nanotube (single- and multi-layer), oxidized titanium, oxidized zinc and quantum dot are targeted. The bureau also explained for what applications these nanomaterials are being used.
However, the study groups decided to hold further discussions on this "definition of nanomaterials," as a number of study group members raised opinions about it. One of them pointed out the target materials include some that are micro-sized with particles clumping together before being dispersed as nano-sized particulates.
Others said some materials range from micro to nano size and the targets include both covalent and non-covalent materials. Based on these factors, the study groups proposed the stance focusing on safety and targeting a wide range of nanomaterials for the time being.
Considering nanomaterials can enter human bodies not only from lungs through breathing but also from skin and digestive systems, the study groups also decided to discuss safety in accordance with entry pathway. Also, a member suggested they should also focus on how to tell and what to consumers in addition to workers.
Based on these proposals, the members requested collection and systematization of information, in a bid to define what subjects the study groups will target in their discussions.
The bureau also outlined the efforts that have been put by the Ministry of Health, Labour and Welfare, other ministries including the Cabinet Office, the US and overseas organizations such as the OECD (Organisation for Economic Co-operation and Development), introducing international trends in the methods to assess the safety of nanotechnologies and nanomaterials as well.
At the second meeting scheduled in April 2008, the study groups are planning to hear and discuss "the state of nanomaterial development, etc" inviting experts.
The third meeting is slated for May, at which the study groups are planning to hear and discuss "information on the toxicity of nanomaterials" and what researches are conducted in the area of safety assessment.
Source: Tech-On (Masaaki Maruyama)