P Goldsworthy

In situ lubricant degradation in Antarctic marine sediments. 1. Short‐term changes

A large-scale, in situ experiment was set up near the Bailey Peninsula area (Casey Station, East Antarctica) to monitor the natural attenuation of synthetic lubricants in marine sediments over five years. Here, we report the short-term changes after 5 and 56 weeks. The lubricants tested were an unused and used Mobil lubricant (0W/40; Exxon Mobil, Irving, TX, USA) and a biodegradable alternative (0W/20; Fuchs Lubricants, Harvey, IL, USA). Clean sediment was collected, contaminated with the lubricants, and deployed by divers onto the seabed in a randomized block design. The sampled sediments were analyzed by gas chromatography-flame-ionization detector and gas chromatography-mass spectrometry with selective ion monitoring. The base fluid of all lubricant treatments did not decrease significantly after 56 weeks in situ. Alkanoate esters of 1,1,1-tris(hydroxymethyl)propane in the biodegradable and unused lubricants were degraded extensively in situ; however, these esters constituted only a minor proportion of the lubricant volume. The additives, alkylated naphthalenes and substituted diphenylamines, were fairly resistant to degradation, which is of environmental concern because of their toxicity. The biodegradable lubricant did not break down to recognized biodegradable thresholds and, as such, should not be classified as biodegradable under Antarctic marine conditions. A separate experiment was conducted to determine the influence of sediment preparation and deployment on compound ratios within the lubricants, and we found that preparation and deployment of the contaminated sediments had only a minor effect on compound recovery. Further monitoring of this in situ experiment will provide much needed information about the long-term natural attenuation of lubricants.

An extreme inland breeding locality of snow petrels (Pagodroma nivea) in the southern Prince Charles Mountains, Antarctica

Abstract Bird observations were made as part of a preliminary biological survey of the southern half of the Mawson Escarpment in the southern Prince Charles Mountains, Mac.Robertson Land between 26 January and 4 February 1998. A new breeding colony of snow petrels (Pagodroma nivea) is described, together with details of individual snow petrel sightings. At 440 km from the coast, the snow petrel colony is the furthest inland of any confirmed breeding site for this species.