Metadata record for data from ASAC Project 2665 See the link below for public details on this project. The Antarctic environment with its harsh climatic conditions, minimal human activity and its unique ecosystems is unlike any of the World's other environments. As such, it is important that an understanding of the Antarctic environment is developed in order to gain a full appreciation of the impacts of human activities in Antarctica and to determine the most effective means to remediate and protect the Antarctic environment. To achieve these goals, new sensitive and selective techniques for sampling metal contaminant levels in marine sediments are being developed. The project is not an environmental study of the Antarctic environment (ie no metal concentrations in water or sediments), but rather the development of an analytical technique for use in Antarctica. We are still in the process of developing this technique and much of the development phase has involved qualitative assessment rather than generating quantitative data. We are currently trialling the technique in the lab and will conduct field trials in the Derwent Estuary. Taken from the abstract of the referenced paper: A novel binding phase was developed for use in diffusive gradients in thin-film (DGT) sampling for Cu(II) by employing methylthymol blue as a chelating and chromogenic agent. Methylthymol blue was adsorbed onto beads of Dowex 1x8 resin (200-400 mesh) and the resin beads were then immobilised onto an adhesive disc. Analysis of exposed binding discs by either UV-vis spectrophotometry or computer imaging densitometry provided robust quantification of adsorbed Cu(II) in the 0.2-1 micro gcm-2 range, allowing detection at micro gL-1 concentrations in the test solution (ca. 17 micro gL-1 for a 24 h deployment), and in good agreement with established DGT theory. The method was shown to be a potential replacement for binding phases based on Chelex 100 where a colorimetric response to a specific metal is desired.

Metadata record for data from ASAC Project 2691 See the link below for public details on this project. Contaminants may persist in marine sediments and be re-suspended during storms or by the activity of animals. This project will assess the impact of contaminated sediments on plants and animals that live directly above the sediment. Rocky-reef organisms form a large component of Antarctica's biodiversity and include algae as well as filter feeding animals such as sponges, lace corals, and fanworms. Many of these plants and animals live on boulders embedded within sediments. Information on the response of individuals, populations and communities to contamination will be used to develop sediment quality guidelines appropriate for the protection of the Antarctic environment. The toxicity of aqueous metals and metal-contaminated resuspended sediment to the spirorbid polychaete Spirorbis nordenskjoldi Ehlers, 1900 was assessed in assays conducted during the 2005/6 and 2006/7 field seasons. A more detailed description of the design of experiments and the methods used can be found in Hill et al, 2009. Spirorbids were exposed to aqueous solutions of copper, lead and zinc singularly, and in mixtures. Spirorbids were also exposed to resuspended metal-spiked sediments. Spirorbids attached to the brown alga Desmarestia sp were collected from Beall Island, Windmill Islands, East Antarctica, a clean site located approximately 2 km from Casey Station. Algae and animals were kept in the aquarium facility on station, in seawater maintained at 1 C and a 12-h light:dark photoperiod. Seawater was constantly aerated and changed every 5 to 6 d. Spirorbids were used within two weeks of their collection and fed once per week with plankton. Spirorbids were removed from the surface of algal blades 24 h before the start of a test, and allowed to recover in a constant-temperature chamber (CTC) at 0.5 C. Immediately before the start of tests, spirorbids were examined, and only healthy individuals were selected for tests. Spirorbids were determined to be healthy if their tentacular crown (fan) was extended and retracted quickly in response to stimuli. The download file contains further information on the data.