Even though our flux calculations were not very sensitive to a range of realistic atmospheric mole fractions, could increased anthropogenic activity in the Arctic reverse the direction of the benzene and toluene fluxes? If we assumed around 50 pmol mol -1 benzene and 30 pmol mol -1 toluene in the marine atmosphere as modelled for the busy shipping corridors of the North Atlantic and North Pacific , the estimated mean saturations would be 159 and 311 %, and the mean fluxes would be 0.011 and 0.026 µmol m -2 d -1 for benzene and toluene, respectively. Assuming that seawater concentrations remain unaffected by shipping, this suggests that even if anthropogenic activity largely increased in the Arctic, benzene and toluene are likely still to be emitted to the atmosphere from the ocean. Ambient air mole fractions above 79 pmol mol -1 benzene and 91 pmol mol -1 toluene would be required to lead to ocean uptake in the Arctic summer (considering the seawater solubilities and the mean benzene and toluene seawater concentrations from this cruise).