This metadata record contains the results from bioassays conducted to show the response of the Antarctic gastropod, Skenella palludinoides to contamination from combinations of Special Antarctic Blend (SAB) diesel, chemically dispersed with fuel dispersant Ardrox 6120. Fuel only water accommodated fractions (WAF), chemically enhanced water accommodated fractions (CEWAF) and dispersant only treatments were prepared following the methods in Singer et al. (2000) with adaptations from Barron and Ka’aihue (2003). WAF was made using the ratio of 1: 25 (v/v), fuel to filtered seawater (FSW) following the methods of Brown et al. (2017). Ratios for chemically dispersed treatments were 1: 100 (v/v), fuel to FSW and 1: 20 (v/v) dispersant to fuel. Dispersant only treatments were made using ratios for CEWAF, substituting the fuel component with FSW. Mixes were made in 5 L or 10 L glass aspirator bottles using a magnetic stirrer to achieve a vortex of approximately 20% in the FSW before the addition of test media. The same mixing energy was used to prepare all WAFs for enhanced reproducibility and comparability of results (Barron and Ka’aihue, 2003). Mixes were stirred in darkness to prevent bacterial growth for 18 h with an additional settling time of 6 h at 0 plus or minus 1 oC. A dilution series of four concentrations were made from the full strength aqueous phase of each mix using serial dilution. WAF test concentrations were 100%, 50%, 20% and 10% while CEWAF concentrations were 10%, 5%, 1% and 0.1%. These concentrations were chosen in order to quantify the mortality curve and allow statistical calculation of LC50 values. To facilitate comparisons of dispersant toxicity in the presence and absence of fuel, dispersant only test concentrations reflected those of CEWAF treatments. WAF was sealed in airtight glass bottles stored at 0 plus or minus 1 oC for a maximum of 3 h before use. Fresh test solutions were prepared every four days to ensure consistent water quality and replace hydrocarbons that adsorbed or evaporated into the atmosphere. Each test concentration was represented by five replicates with five FSW control beakers, with approximately 10 S.palludinoides individuals per replicate. The healthiest and most active individuals were chosen. Beakers were filled to 200 ml and were left open to allow the natural evaporation of lighter monoaromatic hydrocarbon components that would occur during a real spill. Animals were not fed during experiments to prevent hydrocarbons being ingested, thereby introducing an additional exposure pathway. Experiments ran for a total of 35 d exposure duration for WAF and CEWAF experiments and 15 d for dispersant only experiments. Experiments were run in cold temperature-controlled cabinets set at a temperature of 0 plus or minus 1 oC, fluorescent lights in the cabinets were set to a light regime of 18 h light, 6 h darkness, following the methods in Brown et al. (2017) to reflect Antarctic summer environmental conditions. Lethal and sublethal observations were made at test times of: 24 h, 48 h, 96 h, 7 d, 8 d, 10 d and 12 d, 14 d, 16 d, 20 d, 21 d, 28 d and 35 d for SAB + Ardrox 6120 experiments and 24 h, 48 h, 96 h, 7 d, 8 d, 10 d and 12 d, 14 d, 15 d for Ardrox 6120 only experiments. The health status of each individual was classified as per the criteria listed below: - Attached to the vial with horns in or out - Unattached (often upside down), horns out, will reattach if flipped over - Not attached but if touched, will retract - Closed but attached and out of water - Operculum closed - Dead, operculum open a little (muscles no longer working), if touched, operculum will not move and tissues might disintegrate Dead animals were removed and preserved in 80% ethanol at each observation period. In order to simulate a repeated pulse pollutant, 90 to 100% of the test solution volume of each beaker was renewed with freshly made test concentrations every four days to replenish hydrocarbons lost through evaporation and adsorption and ensure consistent water quality. Beakers were topped up to 200 ml between water changes with deionised water to maintain water quality parameters. Duplicate 25 ml aliquots of test concentrations were taken at the beginning and end of each experiment in addition to pre and post water change samples. Samples were immediately extracted with 0.7 μm of dichloromethane spiked with an internal standard of BrC20 (1-bromoeicosane) and cyclooctane. Samples were analysed using Gas Chromatography with Flame Ionisation Detection (GC-FID) and mass spectrometry (GC-MS). Brown, K.E., King, C.K., Harrison, P.L., 2017. Lethal and behavioural impacts of diesel and fuel oil on the Antarctic amphipod Paramoera walkeri. Environmental Toxicology and Chemistry. Animal collection, 2013 experiments: animals sourced from AAD aquarium, collected in previous seasons. Animal collection, 2014 experiments: January and February 2014 Experiments were conducted at the Marine Research Facility at the Australian Antarctic Division in Kingston, Tasmania. Experiments using SAB fuel and the fuel dispersant Ardrox 6120 were conducted in August and September 2013, with additional experiments conducted in May 2014 using Ardrox 6120 only.

Experiments were done to quantify the Total Hydrocarbon Content (THC) in water accommodated fractions (WAF) of three fuels; Special Antarctic Blend diesel (SAB), Marine Gas Oil diesel (MGO) and an intermediate grade of marine bunker Fuel Oil (IFO 180).These tests measured the hydrocarbon content in freshly decanted WAFs and the resulting loss of hydrocarbons over time when WAFs were exposed in temperature controlled cabinets at 0°C. These tests are detailed in Dataset AAS_3054_THC_WAF. The results of hydrocarbon WAF tests were used to calculate integrated concentration from measured hydrocarbon concentrations weighted to time to be used as the exposure concentrations for toxicity tests with Antarctic invertebrates. Exposure concentrations used to model sensitivity estimates were derived by calculating the time weighted mean THC between pairs of successive measurements in the 100% WAFs and dilutions to give overall exposure concentrations for each time point.These modelled concentrations integrated the loss of hydrocarbons over time, and renewal of test solutions at 4 d intervals Exposure concentrations of THC in µg/L are shown for endpoints from 24 h to 21 d

This data set describes the toxicity of marine sediment spiked with undispersed diesel and diesel dispersed with Dasic Slickgone to the Antarctic ophiuroid Ophiura crassa. In 4 experiment ophiuroids were exposed for 10 days with daily observations of the movement of the animals as an indication of health. This work falls under the umbrella project ASAC_2201. The fields in this dataset are: Concentration SAB Time Animals Moving

Full title: Diatom and associated data for a manipulative field experiment examining the effects of heavy metal and petroleum hydrocarbon contamination on benthic diatom communities in the Windmill Islands, Antarctica. A manipulative field experiment was performed to assess the effects of heavy metals and petroleum hydrocarbons on benthic diatom communities in the Windmill Islands. Three treatments were used (control, metal contaminated, and petroleum hydrocarbon contaminated), with replicates of each treatment deployed at three locations (Sparkes Bay, Brown Bay and O'Brien Bay). The datasets associated with this experiment include the concentrations of metals and hydrocarbons within samples, as well as diatom data (raw counts, and the relative abundance of benthic species). This work was completed as part of ASAC project 1130 (ASAC_1130) and project 2201 (ASAC_2201). Public summary from project 1130: Algal mats grow on sea floor in most shallow marine environments. They are thought to contribute more than half of the total primary production in many of these areas, making them a critical food source for invertebrates and some fish. We will establish how important they are in Antarctic marine environments and determine the effects of local sewerage and tip site pollution. We will also investigate the impact on the algal mats of the additional UV radiation which results from the ozone hole. Public summary from project 2201: As a signatory to the Protocol on Environmental Protection to the Antarctic Treaty Australia is committed to comprehensive protection of the Antarctic environment. This protocol requires that activities in the Antarctic shall be planned and conducted on the basis of information sufficient to make prior assessments of, and informed judgements about, their possible impacts on the Antarctic environment. Most of our activities in the Antarctic occur along the narrow fringe of ice-free rock adjacent to the sea and many of our activities have the potential to cause environmental harm to marine life. The Antarctic seas support the most complex and biologically diverse plant and animal communities of the region. However, very little is known about them and there is certainly not sufficient known to make informed judgements about possible environmental impacts. The animals and plants of the sea-bed are widely accepted as being the most appropriate part of the marine ecosystem for indicating disturbance caused by local sources. Attached sea-bed organisms have a fixed spatial relationship with a given place so they must either endure conditions or die. Once lost from a site recolonisation takes some time, as a consequence the structure of sea-bed communities reflect not only present conditions but they can also integrate conditions in the past. In contrast, fish and planktonic organisms can move freely so their site of capture does not indicate a long residence time at that location. Because sea-bed communities are particularly diverse they contain species with widely differing life strategies, as a result different species can have very different levels of tolerance to stress; this leads to a range of subtle changes in community structure as a response to gradually increasing disturbance, rather than an all or nothing response. This project will examine sea-bed communities near our stations to determine how seriously they are affected by human activities. This information will be used to set priorities for improving operational procedures to reduce the risk of further environmental damage. The fields in this dataset are: Species Site Abundance Treatment Type Antimony Arsenic Cadmium Chromium Copper Iron Lead Manganese Mercury Nickel Silver Tin Zinc Special Antarctic Blend Lube