Mitsui & Co. (U.S.A.), Inc.



Mar. 27, 2007

Main Contents

NEW YORK (March 27, 2007) -- Mitsui & Co., Ltd. (Mitsui) announced today a new collaboration between the Company and the National Institute for Occupational Safety & Health (NIOSH) focused on the safety of carbon nanotubes (CNT).

CNT, representing a new class of engineered nanomaterials, are being proposed for multiple uses in the production of new and improved products that will greatly impact the fields of electronics, transportation and medicine, among others. To date, the biological activity of various forms of CNT has not been completely investigated, and a systematic evaluation of the relationship between physicochemical properties of the many types of CNT and toxicological potential has not been conducted.

A workshop entitled "Health Risks of Carbon Nanotubes: What Can We Learn From Mineral Fibers or Ultra-fine Particulates?" held on March 26, 2007 at the Society of Toxicology (SOT) annual meeting, brought together experts from industry, academia, and governmental institutions to present the status of current toxicological and exposure data on CNT, identify knowledge gaps, and outline future directions. Current information concerning the biological activity of single-walled CNT was presented and compared with preliminary findings (intensive qualitative results) on multi-walled CNT. NIOSH investigators are conducting studies of in vivo (animal) responses, while the EPA is investigating biological activity using in vitro (test tube) models. At the SOT Workshop, NIOSH presented its preliminary results for multi-walled CNT, which showed that CNT does not behave like known mineral fibers such as asbestos. The workshop participants agreed that the biological evaluation must be conducted using well-characterized CNT such as Mitsui MWNT-7 as mentioned by NIOSH and others.

Mitsui and Rice University (Rice) have initiated active collaborations with scientists at NIOSH and the Environmental Protection Agency (EPA) to evaluate the biological activity of CNT. Mitsui and Rice are providing well-characterized samples of multi-walled CNT (provided by Mitsui) and single-walled CNT (provided by Rice) manufactured by chemical vapor deposition ( CVD) processes for such studies.

In addition, Mitsui is collaborating with scientists at Shinshu University in Japan to evaluate the biological activity of a well-characterized CNT sample, Mitsui MWCNT-7.

"Safety for innovative materials such as CNT is essential to providing a substantial benefit to human society," said Morinobu Endo, Professor of Electrical & Electronic Engineering, Faculty of Engineering, Shinshu University. "I am pleased that Mitsui's work with Rice University is already resulting in positive preliminary results that will help promote nanotechnology and may allow for substantial industrialization in a few years."

As more complete data are obtained, Mitsui is committed to rapidly disseminating the results so that up-to-date information is available to industry, consumers, and regulatory officials. In the meantime, Mitsui has developed a closed manufacturing system for multi-walled CNT and has installed exhaust and waste treatment systems in the production process. Workplace measurements by the National Environmental Institution in Japan confirm the effectiveness of such controls. In addition, Mitsui recommends to its customers that prudent safety practices be incorporated in the shipment and handling of CNT as outlined in the NIOSH document "Approach to Safe Nanotechnology: An Information Exchange with NIOSH."

Mitsui is pleased to be collaborating with the scientific community to obtain information concerning the bioactivity of multi-walled CNT in an effort to assure the safe manufacture and commercialization of this exciting technology.

About Mitsui USA

MITSUI & CO., LTD. (Mitsui) is one of the world's most diversified and comprehensive trading, investment, and service enterprises. Headquartered in Tokyo, Japan, Mitsui maintains a global network of 172 offices in 72 countries, and has 582 subsidiaries and associated companies worldwide.

The Company's main businesses include sales, manufacturing, export / import, international trade and services in the following fields: metal products and minerals, machinery, electronics and information, chemicals, energy, consumer products and services such as retail, foods, textiles & fashion, general merchandise and various other areas, along with financial markets and logistics & transportation.

Mitsui is engaged in diversifying services, as it explores and develops natural resources, while making commercial investments in the development of technologies for new businesses, and much more.

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For inquiries on this matter, please contact

Mitsui & Co. (U.S.A.), Inc.
Mr. Shinichi Hirabayashi
Director of External Relations
Direct: 212-878-4072