Possible new toxicant indicated in severe air pollution episode in south coast basin

THE PHOTOCHEMICAL air pollution episode that occurred between November 8 and 11, 1973, in the south coast air basin of California, was unusual because the accompanying weather conditions and the resulting injury to vegetation did not fit into the pattern normally associated with attacks of ozone and per-oxy acetyl nitrate (PAN). The injury to leafy vegetables was worse than usual, considering the concentration of phytotoxicants measured.