The Nation-wide Danish Background Monitoring Programme (BOP) collects information on air quality in Danish background areas.
Among the main objectives of the programme are determination of concentration levels and deposition of nutrients, acidifying compounds and heavy metals. Other components of air pollution such as ozone are also measured.
Measurements are performed at 9 different locations (see map). These locations have been selected to represent coastal and island based areas as well as inland areas.
At all sites precipitation is collected over periods between one day to one month by precipitation collectors. The samples are analyzed for their content of nutrients, acidifying components and metal ions. Furthermore, 5 stations are equipped with filter pack samplers to collect compounds in gas or in particle phase.
At two stations pesticides and nitrophenols are measured. The programme was started in 1978. Results are reported in the annual reports (in Danish).
The programme was latest revised in 2004. In addition to the traditional inorganic pollutants a.o pesticides were included.
An overview of the results of background measurements from a 20-year period is given in the report:
