That's according to the US Environmental Protection Agency after they formally declared that "greenhouse" gases endanger health. The principal gas they are concerned about, of course, is CO2 which you and I exhale every time we take a breath - so we're killing ourselves by breathing according to this ridiculous ruling.
It's also worth pointing out that by far the most prevalent greenhouse gas is water vapour. So, according to the barking mad people who make these decisions, water is a dangerous substance.
It just demonstrates how ridiculous this whole thing has become when the product of our breathing and the essential elements of life on earth are declared harmful to public health - but what would you expect when the people who perpetuate this myth are allowed to blatantly lie on TV and in our media without so much as a challenge?
Only this morning on BBC Breakfast, Sir David King - the government's chief propaganda - sorry scientific - advisor declared that they "know" man's activities are responsible for the warming we saw in the 20th century.
They know no such thing - it is supposition based on flawed computer models which have been proven to be incapable of predicting the climate even a year or two in advance let alone 100 years from now. And yet he is allowed to state this as a fact when it is nothing of the sort.
Well, he might as well make the most of it while he can. One day - not that far off in my opinion - the fallacy of the AGW argument is going to be exposed for what it is. And when that happens, the people who have sought to pull the wool over our eyes will have to face some very difficult questions - to say the least.