Toxicity assessment of individual ingredients of synthetic-based drilling muds (SBMs)
MetadataShow full item record
Synthetic-based drilling muds (SBMs) offer excellent technical characteristics while providing improved environmental performance over other drilling muds. The low acute toxicity and high biodegradability of SBMs suggest their discharge at sea would cause minimal impacts on marine ecosystems, however, chronic toxicity testing has demonstrated adverse effects of SBMs on fish health. Sparse environmental monitoring data indicate effects of SBMs on bottom invertebrates. However, no environmental toxicity assessment has been performed on fish attracted to the cutting piles. SBM formulations are mostly composed of synthetic base oils, weighting agents, and drilling additives such as emulsifiers, fluid loss agents, wetting agents, and brine. The present study aimed to evaluate the impact of exposure to individual ingredients of SBMs on fish health. To do so, a suite of biomarkers [ethoxyresorufin-O-deethylase (EROD) activity, biliary metabolites, sorbitol dehydrogenase (SDH) activity, DNA damage, and heat shock protein] have been measured in pink snapper (Pagrus auratus) exposed for 21 days to individual ingredients of SBMs. The primary emulsifier (Emul S50) followed by the fluid loss agent (LSL 50) caused the strongest biochemical responses in fish. The synthetic base oil (Rheosyn) caused the least response in juvenile fish. The results suggest that the impact of Syndrill 80:20 on fish health might be reduced by replacement of the primary emulsifier Emul S50 with an alternative ingredient of less toxicity to aquatic biota. The research provides a basis for improving the environmental performance of SBMs by reducing the environmental risk of their discharge and providing environmental managers with information regarding the potential toxicity of individual ingredients. © 2011 Springer Science+Business Media B.V.
The final publication is available at: http://www.springerlink.com
Showing items related by title, author, creator and subject.
Bakhtyar, Sajida; Gagnon, Marthe Monique (2012)Drilling muds used by the petroleum exploration and production industry have the role of lubricating and cooling the drilling bits and facilitating the transport of crushed rocks to the surface of the well. The chemical ...
Gagnon, Marthe Monique; Bakhtyar, S. (2013)The study investigated the effects of chronic exposure of pink snapper (Pagrus auratus Forster), to synthetic based drilling muds (SBMs). Fish were exposed to three mud systems comprised of three different types of synthetic ...
Bakhtyar, Sajida; Gagnon, Marthe Monique; Webb, Diane; Nguyen, K.; Rabke, S. (2011)Biodegradation rate, along with acute and chronic toxicity, is an important factor in determining the overall environmental performance of drilling fluids (SBFs) used in synthetic-based mud (SBM) formulations. The ...