Letter: Farm antibiotics the real danger

Sir: John Gummer hopes to promote banning the import of genetically altered maize ("Ministers face maize breakout", 4 December). One gathers that the maize in question has been made to have greater resistance to the ills that afflict it while growing. I think it is safe to say that maize and farm animals, or humans, have very few diseases in common: on the surface, the likelihood that the resistant qualities of the altered maize would encourage resistance in the gut flora of farm animals or humans seems slim.

If Mr Gummer were really concerned about the possibility of farming practices generating resistant bacteria, he might consider the present use of antibiotics in dairy and stock herds. Dairy cows are given sufficient antibiotics that their residue prevents milk from souring: typical pasteurised British cow's milk will kill an introduced yoghurt culture, unless the milk has been first heated nearly to boiling to destroy the antibiotics it contains.

The likelihood of this practice encouraging the development of antibiotic- resistant bacteria which pose a danger to human health is not remote. The antibiotics employed - tetracycline, for example - are in common use in human medicine, and cattle and humans have considerable intestinal flora in common, E coli being a prominent example.

C COLEMAN

London WC1