Effectiveness and potential ecological effects of offshore surface dispersant use during the Deepwater Horizon oil spill: a retrospective analysis of monitoring data
The Special Monitoring of Applied Response Technologies (SMART) program was used during the Deepwater Horizon oil spill as a strategy to monitor the effectiveness of sea surface dispersant use. Although SMART was implemented during aerial and vessel dispersant applications, this analysis centers on the effort of a special dispersant missions onboard the M/V International Peace, which evaluated the effectiveness of surface dispersant applications by vessel only. Water samples (n = 120) were collected from background sites, and under naturally and chemically dispersed oil slicks, and were analyzed for polycyclic aromatic hydrocarbons (TPAHs), total petroleum hydrocarbons (TPH), and a chemical marker of Corexit® (dipropylene glycol n-butyl ether, DPnB). Water chemistry results were analyzed relative to SMART field assessments of dispersant effectiveness (“not effective,” “effective,” and “very effective”), based on in situ fluorometry. Chemistry data were also used to indirectly determine if the use of dispersants increased the risk of acute effects to water column biota, by comparison to toxicity benchmarks. TPAH and TPH concentrations in background, and naturally and chemically dispersed samples were extremely variable, and differences were not statistically detected across sample types. Ratios of TPAH and TPH between chemically and naturally dispersed samples provided a quantitative measure of dispersant effectiveness over natural oil dispersion alone, and were in reasonable agreement with SMART field assessments of dispersant effectiveness. Samples from “effective” and “very effective” dispersant applications had ratios of TPAH and TPH up to 35 and 64, respectively. In two samples from an “effective” dispersant application, TPHs and TPAHs exceeded acute benchmarks (0.81 mg/L and 8 μg/L, respectively), while none exceeded DPnB’s chronic value (1,000 μg/L). Although the primary goal of the SMART program is to provide near real-time effectiveness data to the response, and not to address concerns regarding acute biological effects, the analyses presented here demonstrate that SMART can generate information of value to a larger scientific audience. A series of recommendations for future SMART planning are also provided.
KeywordsDeepwater Horizon oil spill Dispersant use TPH TPAH Monitoring Dispersant effectiveness
- Aurand, D., Coelho, D., & Slaughter, S. (2009). The relationship between acute and population level effects of exposure to dispersed oil, and the influence of exposure conditions using multiple life history stages of an estuarine copepod, Eurytemora affinis, as a model planktonic organism. http://rfp.crrc.unh.edu/projects/viewProject.php?PROJECT_ID=15. Accessed 8 Mar 2013.
- Aurand, D., & Coelho, G. (2005). Cooperative aquatic toxicity testing of dispersed oil and the chemical response to oil spills: Ecological Effects Research Forum (CROSERF). http://www.ecosystem-management.net/assets/documents//FINAL%20CROSERF%20REPORT.pdf. Accessed 8 Mar 2013.
- Bejarano, A. C., & Farr, J. K. (2013). Development of short acute exposure hazard estimates: a tool for assessing the effects of chemical spills in aquatic environments. Environmental Toxicology and Chemistry (in press) doi:10.1002/etc.2255.
- BenKinney, M., Brown, J., Mudge, S., Russell, M., Nevin, A., & Huber, C. (2011). Monitoring effects of aerial dispersant application during the MC252 Deepwater Horizon incident In International Oil Spill Conference, Portland, Oregon, a (pp. 7).Google Scholar
- BenKinney, M., Pascal, B., Huber, C., Wood, B., Russell, M., Nevin, A., et al. (2011). Getting SMARTer: recommendations for improving SMART monitoring procedures based on experiences from the Deepwater Horizon response In American Petroleum Institute (Ed.), Proceedings of the 2011 International Oil Spill Conference, Portland, Oregon, b (pp. 6).Google Scholar
- BP (2010). Dispersant studies of the Deepwater Horizon oil spill response Interim Report on Surface Application Evaluations Conducted May 17–27, 2010 http://usresponse.bp.com/external/content/document/2911/989647/1/DISP_App_Studies_Monitoring060810FINAL.pdf. Accessed 8 Mar 2013.
- Brown, J. S., Beckmann, D., Bruce, L., Cook, L., & Mudge, S. (2011). PAH depletion ratios document the rapid weathering and attenuation of PAHs in oil samples collected after the Deepwater Horizon In American Petroleum Institute (Ed.), Proceedings of the 2011 International Oil Spill Conference, Portland, Oregon.Google Scholar
- Clark, J. R., Bragin, G. E., Febbo, R. J., & Letinski, D. J. (2001). Toxicity of physically and chemically dispersed oils under continuous and environmentally realistic exposure conditions: Applicability to dispersant use decisions in spill response planning. In American Petroleum Institute (Ed.), Proceedings of the 2001 International Oil Spill Conference, Tampa, Florida, (pp. 1249–1255).Google Scholar
- Daling, P. S., Brandvik, P., & Reed, M. (1998). Dispersant experience in Norway: dispersant effectiveness, monitoring and fate of dispersed oil. In B. K. Trudel (Ed.), Proceedings of the Conference, Dispersant Use in Alaska: A Technical Update, Anchorage, Alaska, March 18 & 19, 1998 (pp. 111–147): Prince William Sound Oil Spill Recovery Institute, Cordova, Alaska.Google Scholar
- Gugg, P. M., Henry, C., & Glenn, S. (1999 ). Proving dispersants work. In American Petroleum Institute (Ed.), Proceedings of the 1999 International Oil Spill Conference, Seattle, Washington, (pp. 1007–1010)Google Scholar
- Hansen, B. R. H., Nordtug, T., Altin, D., Booth, A., Hessen, K. M., & Olsen, A. J. (2009). Gene expression of GST and CYP330A1 in lipid-rich and lipid-poor female Calanus finmarchicus (Copepoda: Crustacea) exposed to dispersed oil. Journal of Toxicology and Environmental Health, Part A, 72(3–4), 131–139. doi:10.1080/15287390802537313.CrossRefGoogle Scholar
- Henry, C. B., Roberts, P. O., & Overton, E. B. (1999). A primer on in-situ fluorometry to monitor dispersed oil. In American Petroleum Institute (Ed.), Proceedings of the 1999 International Oil Spill Conference, Seattle, Washington, (pp. 5).Google Scholar
- Lehr, B., Sky, B., & Possolo, A. (2010). Oil budget calculator, Deepwater Horizon: technical document. A Report to the National Incident Command. http://www.crrc.unh.edu/publications/OilBudgetCalcReport_Nov2010.pdf. Accessed 8 Mar 2013.
- Lewis, A., A. Crosbie, L. Davies and T. Lunel. (1998). The AEA ’97 North Sea Field Trials on Oil Weathering and Aerial Application of Dispersants In B. K. Trudel (Ed.), Proceedings of the Conference, Dispersant Use in Alaska: A Technical Update, Anchorage, Alaska, March 18 & 19, 1998 (pp. 79–109): Prince William Sound Oil Spill Recovery Institute, Cordova, Alaska.Google Scholar
- Lunel, T., & Davies, L. (1996). Dispersant effectiveness in the field on fresh oils and emulsions. In American Petroleum Institute (Ed.), Proceedings of the 1996 Arctic and Marine Oil Spill Programme, (pp. 1355–1394)Google Scholar
- Lunel, T., Rusin, J., Bailey, N., Halliwell, C., & Davies, L. (1997). The net environmental benefit of a successful dispersant operation at the Sea Empress incident. In American Petroleum Institute (Ed.), Proceedings of the 1997 International Oil Spill Conference, Washington DC, (pp. 185–194)Google Scholar
- Lunel, T., Swannell, R., Rusin, J., Bailey, N., Halliwell, C., Davies, L., et al. (1996b). Monitoring of the effectiveness of response options during the Sea Empress incident: a key component of the successful counter-pollution response. Spill Science & Technology Bulletin, 2, 99–112.CrossRefGoogle Scholar
- McIntosh, S., King, T., Wu, D., & Hodson, P. V. (2010). Toxicity of dispersed weathered crude oil to early life stages of Atlantic herring (Clupea harengus). Environmental Toxicology and Chemistry, 29(5), 1160–1167.Google Scholar
- NCP (2012). National Contingency Plan (NCP) Product Schedule http://www.epa.gov/OEM/content/ncp. Accessed 8 Mar 2013.
- Olsvik, P. l. A., Hansen, B. r. H., Nordtug, T., Moren, M., Holen, E., & Lie, K. K. (2011). Transcriptional evidence for low contribution of oil droplets to acute toxicity from dispersed oil in first feeding Atlantic cod (Gadus morhua) larvae. Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology, 154(4), 333–345.CrossRefGoogle Scholar
- OSAT (2010). Operational Science Advisory Team. Unified Area Command. Summary report for sub-sea and sub-surface oil and dispersant detection: Sampling and monitoring. http://www.restorethegulf.gov/sites/default/files/documents/pdf/OSAT_Report_FINAL_17DEC.pdf. Accessed 8 Mar 2013.
- Pace, C. B., Clark, J. R., & Bragin, G. E. (1995). Comparing crude oil toxicity under standard and environmentally realistic exposures. In American Petroleum Institute (Ed.), Proceedings of the 1995 International Oil Spill Conference, February 27–March 2 (pp. 1003–1004)Google Scholar
- Posthuma, L., Suter, G. W., & Traas, T. P. (2002). Species sensitivity distributions in ecotoxicology. Boca Raton: Lewis Publisher.Google Scholar
- Rhoton, S. L., Perkins, R. A., Braddock, J. F., & Behr-Andres, C. (2001). A cold-weather species' response to chemically dispersed fresh and weathered Alaska North Slope crude oil. In American Petroleum Institute (Ed.), Proceedings of the 2001 International Oil Spill Conference, Tampa, Florida, (pp. 1231–1236)Google Scholar
- RRT 6 (2001). Regional Response Team VI FOSC Dispersant Pre-approval Guidelines and Checklist. Version 4, 2004. http://www.losco.state.la.us/pdf_docs/RRT6_Dispersant_Preapproval_2001.pdf. Accessed 8 Mar 2013.
- Singer, Aurand, D. V., Coelho, G. M., Bragin, G. E., Clark, J. R., Jacobson, S., et al. (2001). Making, measuring, and using water-accommodated fractions of petroleum for toxicity testing. In American Petroleum Institute (Ed.), Proceedings of the 2001 International Oil Spill Conference, Tampa, Florida, (pp. 1269–1274)Google Scholar
- Stoermer, S., Butler, G., & Henry, C. (2001). Application of dispersants to mitigate oil spills in the Gulf of Mexico: The Poseidon Pipeline spill case study. In American Petroleum Institute (Ed.), Proceedings of the 2001 International Oil Spill Conference, Tampa, Florida, (pp. 1227–1299)Google Scholar
- Tan, S. H. (2011). In-situ fluorometry and SMART protocol—The Montara wellhead experience. In American Petroleum Institute (Ed.), Proceedings of the 2011 International Oil Spill Conference, Portland, Oregon, (pp. 1–15)Google Scholar
- USCG, NOAA, USEPA, CDCP, & MMS (2006). Special Monitoring of Applied Response Technologies (SMART). http://docs.lib.noaa.gov/noaa_documents/648_SMART.pdf. Accessed 8 Mar 2013.
- USEPA (1994). Title 40.Part 300.Subpart J—use of dispersants and other chemicals. http://www.ecfr.gov/cgi-bin/retrieveECFR?gp=1&SID=e23357cf8c81ee6d93608879bd30e2fa&ty=HTML&h=L&n=40y126.96.36.199.1&r=PART. Accessed 31 May 2013.
- USEPA (2003). Procedures for the derivation of equilibrium partitioning sediment benchmarks (ESBs) for the protection of benthic organisms: PAH mixtures. EPA-600-R-02-013. http://www.epa.gov/nheerl/download_files/publications/PAHESB.pdf. Accessed 8 Mar 2013.
- Wetzel, D., & Van Fleet, E. S. (2001). Cooperative studies on the toxicity of dispersants and dispersed oil to marine organisms: A 3-year Florida study. In American Petroleum Institute (Ed.), Proceedings of the 2001 International Oil Spill Conference, Tampa, Florida.Google Scholar