Novel Fluorinated Compounds Discovered In Firefighters' Blood
ckwu writes: Perfluorinated compounds help firefighting foams rapidly flow over flaming liquids such as gasoline and jet fuel, cooling and quenching fires. But despite environmental scientists' concerns about these possibly toxic compounds, researchers don't know the identity of many of the chemicals in the mixtures on the market. For the first time, a new study borrows a medical research tool to pinpoint fluorochemicals in the blood of firefighters, identifying novel compounds that have never before been publicly reported.
I would have thought that something used by the fireservice in large quantities and knowingly dispersed into the wider environment would have its chemical composition well known.
There are a multitude of environmental, health and liability issues here and I simply don't buy it that the ingredients are a mystery. I'm sure that there are chemicals available which are excellent at fire fighting but also highly toxic and that those chemicals aren't used because of their lethality.
I can just imaging the defence now. "So Mr Government, you're telling me that you gave firefighters this product, to use on fires in public spaces where both trained personnel and the public can be expected to be and you didn't know what was in it?" "Correct" "Prosecution rests its case"
...this was found in their blood, implying that the firefighters are just evolving a natural defense against fire.
We hardly know everything that is in gasoline (about a hundred compounds, mostly C4-C9 isomers). Jet fuel is more complex and diesel (C10-C20) is just too far gone.
Why would you expect to know the exact isomers (and recemization) in a fluorinated organic? The fluorine will go on in various places. And even if you think you know, it will change once thermally cracked at fire temperatures.
Mostly harmless, but there will be the odd one with just the wrong geometry to do somethink nasty, like the way BPA binds estrogen receptors.
I don't know- I went looking for an MSDS for a modern firefighting foam, and the composition listed is:
Now, this is for Ansul-3 Fluoroprotein foam concentrate. It definitely contains some sort of fluorinated compound (fluoroprotein foam agents are at least known to contain a fluorinated surfactant and hydrolyzed protein); the MSDS has absolutely no mention of what it is. In the Environmental Handling section, all it says is "An environmental hazard cannot be excluded in the event of unprofessional handling or disposal." Nothing about how fluorinated surfactants are persistent environmental contaminants or can cause kidney damage in high doses. It is simply written like innocuous polyethylene glycol is the only component. I've seen material safety data sheets for shampoo that have far more information.
Now, in the specific case covered by the research paper, the "unknown compounds" aren't really that mysterious. They're all either metabolites, chemical precursors, or close chemical relatives (if you're making some some sort of octane derivative, you can expect some hexane to be in there too). And they're all given as 0.1%-1% of the main PFOS surfactant; certainly chemical manufacturers need to exert better control over their processes, minimize byproducts, perform long-term safety studies, etc. And that goes double for anyone making halogenated organic compounds, which now have a substantial record of turning out to be accumulative toxins. But I think if you look at many common manufactured products at trace levels with tandem mass spec, you're going to find some compounds that aren't in the literature.
"FDA staff reviewers expressed concern about the number of patients who were left out of the study because they died."