[Cypress: a new plague for the Rhône-Alpes region?].

Today the Cupressaceae are seen as one of the most allergenic plant families in the mediterranean region. A comparative study of Cupressaceae pollen concentration as sampled in Lyon-Bron (temperate region) and in Montpellier (mediterranean region) has been conducted. During the last 20 years, this family of plant has increasingly been represented in the pollinic spectra. In Montpellier the annual mean pollen concentration went from 43 pollen grains m3 of air at the beginning of the eighties to 72 pollen grains at the beginning of the years 2000. In Lyon, the progression is above 200% but with lesser annual mean pollen concentrations: 4.5 pollen grains m3 of air at the beginning of the eighties to 13.7 pollen grains at the beginning of the years 2000. The annual mean pollen concentration in the Lyon region still modest compared to the mediterranean stations, shows a steep increase though, that should be taken care of.