Thursday, October 8, 1998 Published at 05:09 GMT 06:09 UK
Pollution found in remote snows
Pollution free paradise - not so say the scientists
New research suggests that there are no places on Earth that are free of pollution, a Canadian scientific team says.
The team, writing in the journal Nature, say the pollutants were transported from developed areas and deposited on the ground as snow or rain when the air cooled.
And they say that, since it is likely the same process is going on all over the world, food and water supplies need to be monitored in parts of the globe previously thought to be free of pollution.
Analysis of snow samples from mountains in western Canada showed that organochloride accumulation increased drastically between altitudes of 770m and 3,100m.
Writing in Nature the researchers said: "There is reason to believe that levels of organochlorides in snow would continue to increase at higher elevations.
"Cities like Denver and Mexico City derive their water supply from snow melted on mountains over 3,000m high. They are also much closer to industrial and agricultural sources of contaminants."
The Alberta team says that there is likely to be a "more pronounced accumulation of toxic compounds" in such areas than in the snows of their study area.