A pesticide called methyl bromide is damaging
the Earth's protective shield of .
Farmers use this pesticide to kill tiny worms called nematodes, bugs and weeds
that can affect strawberries, tomatoes and flowers. It is now the third most important
cause of ozone destruction, after CFCs and halons. Its use has doubled in six
years  but now (2004), there's a campaign
to convince US supermarkets to stop selling food grown or treated with methyl
But there is an alternative: methyl iodide
which is no threat to the ozone shield . Why aren't farmers using this instead?
 New Scientist, 11/12/99, 7;  New Scientist, 20/7/96,