Hard to know what to think about this when we know that the estimate is too high, but we have no idea _how much_ too high. From the jet fuel mentioned in the article that has the "1 in 4" cancer risk, the EPA had this to say about it's risk model:<p>The agency assumed, for instance, that every plane at an airport would be idling on a runway burning an entire tank of fuel, that the cancer-causing components would be present in the exhaust and that residents nearby would breathe that exhaust every day over their lifetime.<p>This seems to support their assertion that the modeled risk is unreasonable. But that unfortunately doesn't tell us what it actually is. Also, I'd love to know: was it EPA scientists making these assumptions in their models? If so, then <i>why</i>? The cynical part of me wants to say that it's to create exactly this scenario: They can dismiss the results as unreasonable, and since that's the only version they ran, they don't have reasonable numbers to give us.