Eventually, as scientific data established a clear correlation between smoking and lung cancer, the regulatory landscape shifted towards discouraging smoking.

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The individual connection between exposure to asbestos and lung disease was pretty clear-cut.

ECONOMIST: Environmental risks

It wasn't until Tarceva extended the lives of patients with non-small cell lung cancer that it became clear that OSI and Genentech actually did have a potential blockbuster on their hands.

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In other words, it has not been clear that the immune system can recognize and attack lung tumors.

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It seems to be a pretty clear predictive value: the higher level, higher the lung cancer risk.

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One patient in the Exubera trial developed lung scarring, although it's not clear if it was related to the insulin.

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However, he warned that if there were further, larger eruptions of ash, people with lung problems such as asthma should "stay clear of the ash" by staying indoors and wearing a mask.

BBC: Mount St Helens spews out steam and ash on 5 October 2004

It has been suggested in previous studies that there could be a link between impaired lung function and a negative effect on the thinking processes, but it is not clear what the mechanism for that might be.

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