Atmospheric iodine, selenium and caesium depositions in France: I. Spatial and seasonal variations

The spatial distribution and seasonal variations of atmospheric iodine (I), selenium (Se) caesium (Cs) depositions remain unclear this precludes adequate inputs for biogeochemical models. We quantified total concentrations fluxes these elements in rainfalls from 27 monitoring sites France with contrasted climatic conditions; monthly measurements were taken over one year (starting 2016/09). Since speciation I Se can impact their behaviour the environment, analysis inorganic compounds was also conducted. Our results showed that annual rainfall much higher than those Cs (annual means = 1.56, 0.044 0.005 ?g L?1, respectively). highly positively correlated marine (i.e. Na, Cl Mg), involving under oceanic climate transition, continental mountainous ones. Furthermore, common patterns found between both terrestrial components consistent various sources atmosphere. association two anthropogenic NH4+ NO3?) used agriculture supports hypothesis its origin dusts) rainfall. during warmest months all climates. However, no specific trend occurred Cs. On average, contained mostly unidentified (inorganic proportions 25–54%) equal compounds. Concentrations iodate an marine-origin.