Most of the air pollutants showed higher levels in urban
compared to rural areas (Table 2). The only exceptionwas O3 which
was significantly enhanced at rural sites when considering longterm
data. Except O3 and PM2.5, all pollutants were more variable
(higher standard deviation) in the urban environment. O3 (shortterm)
and PM2.5 (long-term) did also not differ significantly between
urban and rural sites.