10 year trend of organochlorine pollutants in Antarctic seabirds, trends patterns and risks.

Organochlorines, like for instance PCBs, are man-made. Since the 1960s levels of PCBs have risen increasingly. They have hardly been used in Antarctica, which makes this an ideal place to monitor global background levels of these compounds. Monitoring of such background levels is needed in order to evaluate the effectiveness of measures that have been implemented globally to mitigate (local) input of organochlorines into the environment. Furthermore, monitoring of Antarctic species is essential because they may be more vulnerable to contaminants, due to their ecology and their extreme physiological cycle. Additionally, the Antarctic environment itself may be very sensitive to persistent, semi-volatile contaminants, due to the so-called cold condenser effect which results in a directed transport of these contaminants to cold places on earth. The current project is therefor developed with the objective to give insight in the 10 year trend of levels of these contaminants, and in the processes that underlay the transport of these contaminants to Antarctica. In 1991 an extensive project was started, funded by NWO, in which non-destructive methods were developed to collect samples from Antarctic bird species, which could be used to assess contaminant levels in these birds. This resulted in several publications, amongst which a Ph.D.-thesis: Probing for the invisible, by N.W. van den Brink. The collection of samples of blood and preenoil of birds is relatively simple and contaminant levels in types of samples have proven to be representative of levels in other tissues of the birds, and can be used to monitor concentrations in birds (Van den Brink 1997). In the current project identical methods will be used to collect samples from Southern Fulmars and Adélie Penguins, from the same colonies at Hop Island. The application of identical methods at the same geographical location allows for a detailed analysis of organochlorine concentrations between years, which has never been done before. Such an analysis will give insight in the fact whether global background levels are changing in time. Furthermore, the patterns of PCBs will reveal if the co-called &8216;cold-condenser effect&8217; results in elevated levels of volatile contaminants in Antarctic wild-life due to the directed transport of these contaminants to Antarctica. The latter information can be used to assess the susceptibility of the Antarctic ecosystem to other volatile persistent pollutants which may be carried to Antarctica via long-range atmospheric transport (Van den Brink 1997). This is of prime importance in relation to global warming, because increasing temperature on earth may result in a stronger &8216;cold condenser effect&8217; and so more contaminants, and even less volatile ones, may be transported to Antarctica. The sampling methods that will be applied have been described (Van den Brink et al. 1996), and have no adverse effect on the birds that have been handled. The methods are simple, and can be applied by instructed people. The fieldwork will be completed in the season 2003/2004. The chemical and statistical analyses will take approximately 6 months after which the results will be prepared for publishing. It is expected that the submission of a manuscript may be achieved at the end of 2004.