Really unsurprised considering how much Budweiser and Spam the people of the Mariana Islands consume.
EDIT: Pure speculation, but given remoteness and how well preserved they are, I suspect they're the litter of commercial fishermen.
If this reference[1] is historically accurate, then the Budweiser is from circa 70s or early 80s, a period before I was conceived and probably predates what would have been a convenient Born On Date reference that Anheuser-Busch made popular.
The relevant production stamp on the Spam can reads F01031, and if we were to trust this reference[2], then it decodes to plant location F (199N cross-references to a plant in Fremont, NE[3]) manufactured January (01) 3rd (03), with certain ambiguity in the year code 1. Observe Hormel Foods label, so this comes from after 1993 name change as suggested by this brief history[4], leaving 2001 or 2011. The styling of 25% LESS SODIUM label cross-referenced against this guy's collection archive[5] factors out 2011, deductively pointing to 2001. Other clues considered include rough time period for when Spam Stuff marketing was a thing, and lack of BEST BY date which is included on the bottom of Spam cans manufactured today.
Thing is, none of this becomes definitively cool for at least another 100 million years after we go extinct, when the universe resumes an era of prehistory prior to the next intelligent life form to emerging from some primordial soup.
Worse still, if that inter-historic era never occurs due to the persistent presence of intelligent machines.
At that point, all bets are off, as to whether even remnants of our pollution might remain, in the face of pervasive systems engineered to keep ecosystems free of the detritus of human civilization, and automatically recuse themselves from pristine areas that require no further stewardship.
Not trying to downplay the issue because their are serious implications of PCB exposure, but the article just says "PCBs were detected" in marine life. The real question is how much?
As a former chemist, we have a ridiculous ability to detect chemicals. It's not unusual to have lower detection limits in the parts per trillion or lower. For reference 1 ppt is 1 mg of chemical in 1000 metric tons of water (or a cube of water 10 m on each edge). We can detect it, but the likelihood is that it doesn't have an impact.
Looking at the paper quoted in the article, PCB concentration was ~100 ppb of dry weight, which would be less looking at wet weight (the nature state of the organisms).
I just want to say it really depends on the chemical and location in the food chain. Something that's stable and bioaccumulates can have meaningful impact on top preditors even with extremely low initial concentrations.
Especially if it is unusually potent. To use a famous example the LD 50 on VX is ~7 µg/kg. Now, picture something like that that also bioaccumulates.
Former epa intern here; can concur, chlorinated anything is trivially detected with an ECD. Biological activity of the chemical under analysis has nothing to do with its detectability.
Industry develops and retracts chemical classes in waves without seeming to absorb the larger lesson.
I've studied environmental and industrial chemistry and I'm not sure exactly what larger lesson the author thinks was available for the taking but left unabsorbed by industry. The highly halogenated structures that dominate persistent organic pollutants (it's the multiple fluorine/chlorine/bromine atoms that cause persistence, not the benzene ring) were largely developed in an effort to improve human welfare. PCBs were not flammable, so safer for use in hot transformers than earlier plain-hydrocarbon dielectric fluids. Polybrominated diphenyl ethers show up in furniture and clothing because they are effective flame retardants. They became ubiquitous in direct service to human safety. DDT seemed, initially, like a miraculous savior of human health and crops from harm by insects.
After many real-world cautionary examples, the availability of better bench screening assays, and the development of quantitative structure-activity relationship models, today we can have a pretty good idea of whether a compound will be an endocrine-disrupting persistent organic pollutant before it becomes a high volume industrial product. None of these lessons or tools were available in the first half of the 20th century when these chemicals entered the mainstream of industry. Animal tests were around, of course, but the insidious thing about a lot of POPs is that they don't have obvious, acute health consequences. The LD50 may be quite high. If you're just trying to figure out "will this kill exposed workers/consumers," the assays won't reveal that (e.g.) long term thyroid function suffers in exposed mammals, or see endocrine effects that interfere with sexual organ development in young animals. You don't know what you don't know.
All that said, I certainly can and do criticize the modern chemical industry for foot-dragging, delaying tactics deployed against regulating chemicals that have demonstrated obvious ill effects in animals, or that are so structurally similar to other POPs that they really shouldn't maintain grandfathered approvals. It took until last year for the EPA to regulate perfluorooctanoic acid in drinking water, whose formula alone should ring chemists' alarm bells with regard to bioaccumulation and persistence: https://en.wikipedia.org/wiki/Perfluorooctanoic_acid
It's arguably prudent to avoid any organic compound that doesn't degrade appreciably in typical aerobic and anoxic environments. Maybe that wasn't well appreciated decades ago, but it's pretty obvious now. The comparison of PAHs (polycyclic aromatic hydrocarbons) and PCBs is instructive. Their toxicities are broadly similar. But PAHs degrade quickly, whereas PCBs accumulate.
"DDT seemed, initially, like a miraculous savior of human health and crops from harm by insects."
DDT saved over 0.5 billion lives before it was banned in the USA.In India, between 1952 and 1962, DDT caused a decrease in annual malaria cases from 100 million to 60,000. By the late 1970s, no longer able to use imported DDT, the number of cases increased to 6 million. India now synthesises it's own DDT and uses it. It is still made and widely used. Worldwide production was around 5 million tons last year.
Penicillin is the only manmade substance that has saved more lives than DDT.
DDT is still allowed to be used for indoor residual spraying by the WHO.
People go all ape st over the potential for radioactive waste contamination, but I think its only a matter of time before we cover the planet in something that really messes with higher life forms in a massively negative way. This may have already happened, and we don't even know it.
Its going to be a case of "hey look a new Plasticizer/dye/whatever, is awesome lets use it in all the new $ConsumerProducts", followed by the realization later after we have basically lets it contaminate every cubic inch of water/soil/air that it damages some fundamental aspect of our biology and is the cause of massive cancer rates/birth defects/IQ loss/whatever.
So, the question is, do you think our knowledge of mammal biochemistry is sufficient to have models that can predict every form of possible damage?
Put another way, is endocrine disruption the only pathway to serious long term biological damage?
Do we even know enough to answer those questions accurately?
I think the larger lesson is to stop assuming that whatever confirmation bias laden evidence you've collected to date regarding the benefits of your new compound do not present a full picture of the dangerous repercussions.
There's a lake not far from me in Raleigh, NC that I often run past. The lake is used for recreation. It's also an EPA Superfund site because a company long since out of business, Ward Transformers, saw fit to dispose of its polutants right into a ditch behind the plant. The chemicals ran off into the lake and streams for miles. All the nearby waterways warn not to eat the fish caught therein.
At one point, a contractor hired by the company to dispose of the chemicals was caught spraying them along rural roadsides.
"How PCBs reached the Mariana is still under investigation"
Well in Western Australia PCB's by the truckload in 44 Gallon Drums were dumped into the ocean and left to rust away off South Fremantle for many many decades, so this does not surprise me if this was happening all over the world.
For HN audience, the most recognizable older source that uses it a lot might be Neal Stephenson's Zodiac from 1988 :), but the chemicals are much older than that.
Yep, and the disposal method for those old transformers was far too often "throw it in the woods down the street".
Every so often the local news will do a story when someone finds another pile of rusty and leaking transformers sitting on a lot behind a daycare or something.
Poly-Chlorinated Biphenyls? What other acronym would they use?
Or is it just that some might find it contentious with Printed Circuit Board?
Three letter acronyms are always suffering from name space collisions, in mixed or broad context.
It’s really a symptom of using three letter acronyms at all, rather than any one acronym being reasonably preferable to another under any circumstances. When you only have a symbolic trigram combining any of 26 letters, reuse is not just inevitable but frequent.
It seems almost inconceivable that a long-form humanistic article like this would omit the fact that Kekulé discovered the ring structure of benzene in a dream about the ouroboros:
Can confirm, just disabling JS gets around almost all anti-adblock, as well as speeding up pageload by 10-20x and removing obnoxious stuff from the page.
The really bad blocker blockers use noscript <meta refresh> headers, which most JavaScript blockers don't do anything to. Weirdly, I've only ever seen those on local newspaper websites. They just force redirect to a nastygram if you aren't running JavaScript.
