RF–Akvamiljø
The exploration and development of offshore oilfields has been under way for many decades and, for much of this period, the effects of such activities on the environment and its inhabitants was poorly understood. In recent years it has been recognised that these regions require our protection and this is reflected in the increasingly demanding legislation designed to safeguard them. As the search for new oil reserves continues, fields are being developed within increasingly sensitive environmental areas and it is essential that we have the tools at our disposal to detect and measure deleterious changes in biota. In assessing ecological impact arising from industrial activity it is typical to focus on the success or otherwise of a few selected species, chosen perhaps for their rarity or commercial value. While these organisms do indeed require special attention, it is also important for us to recognise the importance of protecting the wider ecosystem, which provides the basis for the continued existence of its component populations and communities.
The dispersion of chemicals used in the process of extracting oil and gas, together with natural compounds released in the discharged produced water, all pose a potential toxic risk to the health of biota. Cleaner extraction and processing technologies are one way of reducing this risk but, as many of the older fields mature, their discharge of produced water increases.
In an effort to reduce the impact that these increases might have, the Convention for the Protection of the Marine Environment of the North-East Atlantic (“the OSPAR Convention”) has proposed a reduction in the oil content of produced water from 40 parts per million (ppm) down to 30ppm by 2006. Even at these lower concentrations, it is essential to assess the risk that these introduced compounds pose to the marine environment and this is one of the key roles played by the skilled scientists and technicians at RF-Akvamiljø in Stavanger, Norway. Using a combination of established methodology and pioneering new research RF-Akvamiljø is carrying out vital investigations into the interactions between oil and gas exploration discharges and the surrounding biota. It is only by fully understanding these interactions and developing accurate and reliable means of detecting and measuring them that we can evolve a strategy for effectively monitoring the health of marine ecosystems in the vicinity of oil and gas field developments. Even with the advent of new techniques such as re-injection of produced water or the CTour process that removes hazardous substances from the produced water prior to discharge, an array of effective biological effect measurement tools will have a role to play in monitoring the area for process malfunctions.
Acute toxicity tests, in which model organisms are exposed to known concentrations of specific chemicals in a controlled laboratory environment, have traditionally been used to rank the degree of toxicity of various chemicals against one another. Figures arising from these tests are then fed into the process of Environmental Risk Assessment (ERA). ERA is currently the primary means for setting control measures for the release of chemicals into the marine environment worldwide. The procedure combines information from four major components, hazard identification, dose-response assessment, exposure assessment and risk characterisation, to derive a level of risk for a particular chemical or process. The use of large safety factors in the final formulation of the risk assessment accommodates the level of uncertainty that this method generates. Research at RF-Akvamiljø is seeking to reduce this level of uncertainty in such assessments and, in addition, provide data with greater ecological relevance by examining the results of chronic exposure of organisms to low, environmentally relevant, concentrations of chemicals.
The absence of sub-lethal measures of biological effect is a further weakness in ERA methodology that is being addressed at RF-Akvamiljø. Changes in biological responses of organisms at the molecular, cellular or whole animal level, following their exposure to pollutants, can be defined as biomarkers of pollution. These sensitive indicators of potential harm can provide a vital input into the process of protecting the marine environment by providing early warning signals of possible later, much more serious, consequences. There are currently over 20 biomarkers in development and use at our laboratories.
Category:
Health & Safety
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