It found the US had "by far the highest rate of first-day deaths among industrialised nations" - more than twice the amount (11, 300) of the entire EU (5, 800).
For many years, economists have observed that as agrarian societies industrialised, pollution increased at first, but as the societies grew wealthier it declined again.
In a separate development, the White House has announced President Clinton will hold his first summit meeting with Mr Putin, before the G8 gathering of leading industrialised countries in Japan in July.