Ohio scientists have demonstrated that diesel exhaust induces the growth of new blood vessels that send blood to supply to solid tumors. This is the first evidence of how exposure to diesel fumes can cause cancer.

The researchers found that more new blood vessels sprouted in mice exposed to diesel exhaust than did in mice exposed to clean, filtered air. The same changes happened in both healthy mice and in sick animals. This suggests, the scientists say, that previous illness isn’t required to make humans susceptible to the damaging effects of the diesel exhaust.