Organic compounds in cloud and rain water

Cloud and rain water samples have been collected in spring 1991 in the Vosges mountains and analyzed for aldehydes, phenols and polycyclic aromatic hydrocarbons (PAH). Both passive and active cloud collectors have been employed. A mean concentration of formaldehyde of 197 müg/l has been found in cloud water while on the average only 100 müg/l were observed in rain water. The average phenol concentration was 3.5 müg/l, but only 1.6 müg/l in rain water. Finally, the mean concentration of PAHs (only determined in cloud water) amounts to 0.37 müg/l. Th PAH profile is similar to that observed for rain water sampled in Hannover (Germany).