Effect of SO(2) and O(3) on Production of Antioxidants in Conifers.

Production of antioxidants was investigated in needles of fir (Abies alba Mill.) and spruce (Picea abies (L.) Karst) after exposure to low concentrations of SO(2), O(3), and a combination of both pollutants. Glutathione reacted most sensitively to pollutants followed by vitamin E and vitamin C. In spruce needles, the overall increase of antioxidants after exposure to air pollutants was lower than in needles of fir. SO(2) was more potent than O(3). Maximum increase of antioxidants was found in needles after exposure of trees to SO(2) + O(3).