OIL SPILL BIOREMEDIATION AGENTS—CANADIAN EFFICACY TEST PROTOCOLS
ABSTRACT Thirteen commercial oil spill bioremediation agents (OSBAs) were tested over a two-year period during the development of a screening protocol designed to evaluate the hydrocarbon degradation efficacy of OSBAs under warm freshwater or cold marine water conditions. The OSBAs were added at the rate specified, to shaker flasks containing a standard test oil, nutrients if requested, and a defined medium. Standardized freshwater or marine microbial inocula were developed to act as internal controls for the screening protocol, that is, to ensure that conditions were suitable for oil biodegradation to occur in each test performed. After the incubation period, the oil was extracted and analyzed using gas chromatography/mass spectrometry (GC/MS) and gas chromatography with a flame ionization detector (GC/FID). The warm freshwater efficacy method exhibited good reproducibility but the cold marine test requires further refinement. The minimum acceptance standard for products tested under standard warm freshwater conditions is currently based on the product achieving GC-detectable total petroleum hydrocarbon (GCD-TPH), aliphatic, and aromatic reductions of 35, 30, and 10 percent, respectively, when compared with the weathered Alberta Sweet Mixed Blend (ASMB) source oil. These values may be adjusted with further experimental testing. Products with acceptable efficacy and toxicity results will be assumed to have good potential application in spill cleanup and will be identified as such to the spill response community.