In our reliance on modern technology, previously obscure chemical compounds are making their way into the manufacturing mainstream, including into workplace air.

One of these compounds is indium-tin oxide (ITO), used to make products such as flat-panel displays, touch screens, solar panels, energy-efficient windows, and many other products.

Although these high-tech products may benefit the consumer, a growing body of research indicates workers making and reclaiming products containing ITO are at risk for indium lung disease.

Indium Lung Disease

Studies describe this as a serious and potentially fatal condition that can progress from early filling of the lung’s air sacs with fluid to later lung scarring and emphysema.

Indium can be detected in the blood of ITO workers, and workers with higher concentrations of indium in the blood appear to be at greater risk.

However, the precise relationship between the level of exposure to airborne indium compounds and risk of indium lung disease is unclear.

For one thing, scientific evidence needed to relate workplace air concentrations of indium with concentrations in the blood of exposed workers has been lacking.

New Study Confirms Health Risks

In a recent study, NIOSH investigators and their partners helped to fill this gap.

They recently found a correlation between the amount of indium in the workplace air and early signs of lung disease among a group of ITO workers, as reported in the peer-reviewed American Journal of Industrial Medicine.

In this study, investigators examined blood concentrations of indium, air concentrations of indium, and lung health among a group of 87 volunteer study participants currently employed in the ITO industry.

The amount of indium in the blood reflected the air concentration of indium and the time employed in the ITO facility.

They found that the amount of indium in the blood reflected the air concentration of indium and the time employed in the ITO facility.

In addition, the workers exposed to respirable indium for nearly two or more years had more shortness of breath, lower lung function, and higher levels of markers in the blood for lung damage than did workers with fewer than two years of exposure.

In other findings, the study showed that those health effects occurred among workers in the study group who had relatively low levels of exposure to indium in the air.

Further studies of other groups of ITO workers with longer and different types of work-related exposure to indium are important to confirm this study’s findings.

Nevertheless, the findings support precautionary efforts to reduce work-related exposure to respirable indium, according to the authors.