Air monitoring stations Were set up at 2 sites in thesouthern hemisphere – Moody Brook, Falkland Islands (51 ~ 25′ S, 57 ~ 56’W) and Halley, Research Station, Antarctica (75 ~ 35′ S, 26 ~ 30′ W). PCBs were monitored at the stations throughout 1999. Highest concentrations were observed when temperatures were greater. In general, concentrations were greater at Moody Brook than at Halley, although the difference in concentrations between sites was less for more chlorinated congeners. Air concentrationsat both sites were compared with samples collectednearby over-water. Over water air concentrations were foundto be greater than over land air concentrations. Concentrations were also compared with literature data for air concentrations at a remote site in the Canadian Arctic. Atmospheric concentrations of tri-chlorinated biphenyls were found to be approximately double those reported for Ellesmere Island in the Canadian Arctic, whilst concentrations in samples from Antarctica were verysimilar to those found in the high Arctic. Most other PCBs were a factor of 2-4 greater in the Canadian Arctic.