Re: "...Neonicotinoid Insecticides in Wetlands of Canada." Paper in PLOSOne.
I see from you profile that you are in the medical research field and as you said, measure very small things. Environmental testing laboratories are completely different and are not equipped to get to that level of accuracy ($$). Microgram (µg) levels are the best that you can hope for. I typically see results reported as < 5 µg/L E (E = estimated qualifier) or ND (not detected) with a 5 µg/L reporting limit. That is kind of bad when the regulatory limit is 2 µg/L, as is the MCL for vinyl chloride. I have seen nanogram levels reported for dioxin testing and the QC is all over the place. After a thorough QC check by one of our chemists, the data is unusable. Percent recoveries, split samples, duplicates, MS and MSDs are all out of spec. And these would be EPA CPL (Contract Laboratory Program) environmental laboratories.
Originally Posted by nschomer
That is why I laugh when I see environmental results reported that are 3 orders of magnitude below the microgram level.
Not to offend anybody posting on this thread, but I also have to laugh when I see comments from people that do not know what the difference between milligram, microgram, and nanogram is; that they are all units of mass; and that concentration is reported in mass/volume.
Honey Badger Don't Care ಠ_ಠ ~=[,,_,,]:3