Toxicity of the weathered crude oil used at the Newfoundland offshore burn experiment (NOBE) and the resultant burn residue

The toxicity of the weathered crude oil Alberta sweet mixed blend (ASMB) used at the Newfoundland offshore burn experiment (NOBE) and the resultant burn residue, was investigated using the Environment Canada water-accommodated fraction (WAF) preparation method and exposure protocol. Rainbow trout ( Oncorhynchus mykiss) were exposed to freshwater WAF prepared from weathered ASMB. Three-spine stickleback ( Gasterosteus aculeatus), and the gametes of the white sea urchin ( Lytechinus pictus) were exposed to saltwater WAF prepared from both weathered ASMB and burn residue. The fish tests were of 96 h duration, and the end-point was lethality. The urchin test was of 20 min duration, and the end-point was inhibition of fertilization. GC/MS headspace analysis of 28 analytes showed low levels of volatile hydrocarbons. The maximum measured concentration was 1.1 μg ml −1 in 104 samples from all WAF concentrations in both seawater and freshwater at all exposure times (0, 24 and 72 h). All samples were found not to be toxic to all species tested.