Ground based in situ observations of high_vol_sampler at Villum Research Station, Station Nord (DK0010G). These measurements are gathered as a part of the following projects CAMP, EMEP and they are stored in the EBAS database (http://ebas.nilu.no/). Parameters measured are: HCB in air (mass_concentration_of_hexachlorobenzene_in_air), PCB_101 in air (mass_concentration_of_polychlorinated_biphenyl_101_in_air), PCB_114 in air (mass_concentration_of_polychlorinated_biphenyl_114_in_air), PCB_118 in air (mass_concentration_of_polychlorinated_biphenyl_118_in_air), PCB_138 in air (mass_concentration_of_polychlorinated_biphenyl_138_in_air), PCB_153 in air (mass_concentration_of_polychlorinated_biphenyl_153_in_air), PCB_170 in air (mass_concentration_of_polychlorinated_biphenyl_170_in_air), PCB_180 in air (mass_concentration_of_polychlorinated_biphenyl_180_in_air), PCB_194 in air (mass_concentration_of_polychlorinated_biphenyl_194_in_air), PCB_206 in air (mass_concentration_of_polychlorinated_biphenyl_206_in_air), PCB_209 in air (mass_concentration_of_polychlorinated_biphenyl_209_in_air), PCB_28 in air (mass_concentration_of_polychlorinated_biphenyl_28_in_air), PCB_3 in air (mass_concentration_of_polychlorinated_biphenyl_3_in_air), PCB_52 in air (mass_concentration_of_polychlorinated_biphenyl_52_in_air), PCB_8 in air, aldrin in air (mass_concentration_of_aldrin_in_air), alpha_HCH in air (mass_concentration_of_alpha_hexachlorocyclohexane_in_air), beta_HCH in air (mass_concentration_of_beta_hexachlorocyclohexane_in_air), cis_CD in air (mass_concentration_of_cis_chlordane_in_air), cis_NO in air (mass_concentration_of_cis_nonechlor_in_air), dieldrin in air (mass_concentration_of_dieldrin_in_air), endosulfan in air (mass_concentration_of_endosulfan_in_air), endrin in air (mass_concentration_of_endrin_in_air), gamma_HCH in air (mass_concentration_of_gamma_hexachlorocyclohexane_in_air), heptachlor in air (mass_concentration_of_heptachlor_in_air), heptachlorepoxide in air (mass_concentration_of_heptachlor_epoxide_in_air), op_DDE in air (mass_concentration_of_op_dichlorodiphenyldichloroethylene_in_air), op_DDT in air (mass_concentration_of_op_dichlorodiphenyltrichloroethane_in_air), pp_DDD in air (mass_concentration_of_pp_dichlorodiphenyldichloroethane_in_air), pp_DDE in air (mass_concentration_of_pp_dichlorodiphenyldichloroethylene_in_air), pp_DDT in air (mass_concentration_of_pp_dichlorodiphenyltrichloroethane_in_air), trans_CD in air (mass_concentration_of_trans_chlordane_in_air), trans_NO in air (mass_concentration_of_trans_nonachlor_in_air)