Fullerenes, those soccer ball-shaped carbon molecules also known as "buckyballs," have generated outsized expectations ever since their discovery in 1985. Scientists think they could eventually be used in chemical sensors, fuel cells, drug delivery, cancer medicines, and smart materials. Yet while commercial demand for fullerenes is gradually emerging, so are fears that these molecules, which measure only a few billionths of a meter across, pose serious health and environmental hazards.

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