National Environmental Monitoring Programme in Sweden. Measurements of persistant organic pollutants in air and precipitation are carried out at Råö, Hallahus, Aspvreten, and in Pallas (Northern Finland). The monitoring programme includes measurements of: polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB), some pesticides (HCH, DDT) and polybrominated diphenylethers (PBDE).