For example of samples collected using one of these techniques: https://publiclab.org/wiki/sampling
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According to the Surfrider group, which sent many oil samples to different labs over the course of the BP oil spill response, “When we were doing our oil study, we ran batches of ten samples using the 8272 modified solids GCMS method @ $295/sample so, $2995 a set. This was with the understanding that we would be running a lot of samples, so may not reflect the usual pricing.” This is how the per-sample cost broke down from the lab analysis for a lab contracted to run samples in batches:
Costs for oil testing vary widely, to as much as $2000 a sample for dispersant testing (according to Surfrider) and as as much as $10,000 for testing with PACE labs according to Scott Eustis (@eustatic) of the Gulf Restoration Network.