Smog--its origin.
D000397:Air Pollution; D000818:Animals; D001249:Asthma / Q000209:etiology*; D002417:Cattle; D006168:Guinea Pigs; D006801:Humans; D011656:Pulmonary Emphysema / Q000662:veterinary*; D051381:Rats; D013729:Terpenes / Q000009:adverse effects*
D013729:Terpenes