Research: Nanotubes Can Attack the Immune System

Inhaling carbon nanotubes can suppress the immune system, according to new research carried out by theLovelace Respiratory Research Institute in Albuquerque, New Mexico.

Carbon nanotubes are rolled-upsheets of graphite thousands of times thinner than a human hair. Because they are immensely strong andare good electric conductors, they are poised for use in a wide range of fields from engineering to medicine.However, there are concerns over the similarities in shape of nanotubes and those of asbestos fibres, whichare known to cause damage to the lungs in conditions such as mesothelioma.

Scientists are therefore trying to work out if there are any adverse effects that nanotubes might have onhuman health.

The findings raise possible health concerns for those working in the manufacture of the materials. The alertfollows earlier animal studies suggesting carbon nanotubes (CNTs) may be capable of causingmesothelioma - a cancer normally associated with asbestos exposure.

In the new study on mice, researchers found that inhaling nanotubes affected the function of T cells, a typeof white blood cell that organises the immune system to fight infections. Because accurate levels ofoccupational exposures remain unknown, it should be noted that rough estimates indicate that if humans areexposed to 1 mg m-3 nanotubes in a similar setup, the burden on the lungs of humans would beapproximately 7.5 times less than the burden experienced by the mice in this study. However, the authorssuggest that with increasing production of carbon nanotubes and possible occupational exposures that willpersist for much longer than the duration of this study, immune dysfunction may be a concern for thoseworking in the industry.

An abstract of the research: Mechanisms for how inhaled multiwalled carbon nanotubes suppress systemicimmune function in mice can be downloaded from here.