Chris, in general I agree with you, but one of the most interesting studies of recent times found that the rate of asthma in Sweden (majorly green country) far exceeded that of East Germany (industrial smog). This appears counter intuitive and I'm not aware of any explanation for it.

My own (and my son's) asthma has been controlled without drugs for many years now, basically after we removed wall to wall carpets from our life and changed from a modern 'seal all the draught points and use central heating' house to an old, notionally dusty, but well ventilated house.

Asthma in the west needs investigating by intelligent people who do not have a drug to push.

Andy