Long range transport of photochemical ozone over the Tyrrhenian Sea demonstrated by a new miniaturized bioassay with ozone-sensitive tobacco seedlings

An innovative miniaturized kit, based on the use of 2-week old supersensitive tobacco seedlings (Nicotiana tabacum L. cv. Bel-W3) raised in tissue culture plates was utilized, in conjunction with two calibrated automatic analyzers, to monitor ozone along a land-to-sea transect during the warm season of 1993. The recurrence of phytotoxic levels of ozone of a photochemical nature was evident on the islands of Capraia and Gorgona, located 55 and 27 km, respectively, to the west of the Tuscan coast (Central Italy), in the open Tyrrhenian Sea. The possible explanations for the results obtained are discussed.