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Banned Chemicals From 1970's Persist In Deepest Reaches of the Pacific Ocean, Study Shows (bbc.com) 74

walterbyrd quotes a report from BBC: Scientists were surprised by the relatively high concentrations of pollutants like PCBs and PBDEs in deep sea ecosystems. Used widely during much of the 20th Century, these chemicals were later found to be toxic and to build up in the environment. The results are published in the journal Nature Ecology and Evolution. The team led by Dr Alan Jamieson at the University of Newcastle sampled levels of pollutants in the fatty tissue of amphipods (a type of crustacean) from deep below the Pacific Ocean surface. The pollutants found in the amphipods included polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), which were commonly used as electrical insulators and flame retardants. PCB production was banned by the U.S. in 1979 and by the Stockholm Convention on Persistent Organic Pollutants, a UN treaty signed in 2001. From the 1930s to when PCBs were banned in the 1970s, the total global production of these chemicals is estimated to be in the region of 1.3 million tons. Released into the environment through industrial accidents and discharges from landfills, these pollutants are resistant to being broken down naturally, and so persist in the environment. The authors of the study say that the deep ocean can become a "sink" or repository for pollutants. They argue that the chemicals accumulate through the food chain so that when they reach the deep ocean, concentrations are many times higher than in surface waters.
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Banned Chemicals From 1970's Persist In Deepest Reaches of the Pacific Ocean, Study Shows

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  • And also (Score:3, Funny)

    by rossdee ( 243626 ) on Monday February 13, 2017 @10:33PM (#53862773)

    MH370

    • by quenda ( 644621 )

      INDIAN!!! [youtube.com]

    • by Anonymous Coward

      Perfect. It means that the chemicals migrate to the deepest holes, accumulate there and will be internalized by the earth in the next quake. So in future, to dispose of this stuff, we can simply pour it down any drain and it will eventually get to the Mariana trench.

  • Surprising that people think seafood is healthy.

    • Surprising that people think seafood is healthy.

      The ocean is pretty big though.

      • by drinkypoo ( 153816 ) <martin.espinoza@gmail.com> on Monday February 13, 2017 @11:33PM (#53863025) Homepage Journal

        The ocean is pretty big though.

        Bioconcentration is the reason why dilution is not the pollution solution.

        • by Anonymous Coward

          On the other hand, what if this means homeopathic medicine does work!

          Oh god, the science!

        • Re: (Score:3, Funny)

          by Anonymous Coward

          If you aren't part of the solution, you are part of the precipitate.

      • by Anonymous Coward

        Unfortunately they avoid giving any sense of how much accumulation there really is. We have such sensitive instruments these days we can practically detect a molecule in a mountain. The concentrations discovered are likely so low that they don't even register on any risk scale. Its an interesting phenomena to understand and learn from, but its not likely a problem, from an exposure standpoint, for aquatic life.

        • by Ranbot ( 2648297 )

          The study summary in the Nature.com link gives the analytical results, and yes the values very low, orders of magnitude lower than any human-health PCB standard in the US that I'm aware of (I'm an environmental consultant), so if we were eating seafood from the marianas trench (we do not) it's unlikely there would be any health risk to humans. However, it's very hard know what contaminant concentrations pose a risk to specific animal species and a lot more study would be needed. Don't hold your breath thoug

    • by Maritz ( 1829006 ) on Tuesday February 14, 2017 @04:38AM (#53864021)
      This might blow your mind, but the fish I and other normal people eat doesn't come from the fucking Mariana trench.
      • by fnj ( 64210 )

        Good point. However, wherever the fish you eat do come from, bioconcentration is most assuredly taking place. That is also true for plants and land (farm and wild) animals.

  • I have been looking all over for them.
  • Toxic chemicals that build up in the environment found to build up in the environment!!!
  • Someone please fill me in on what ng g1 dw is. I get the nanograms, I get the inverse grams. WHAT IS A dw. Thanks

    • From the second link in the summary, to the scientific paper: dw = "dry weight".

    • ng * g ^-1 :

      nanograms [of the polluant, found] per gram [of the medium].

      10 ng * g ^-1 :
      if you take 1 gram of the soil of the bottom of the pacific ocean, you'll find that it contains 10 ng of the plastic polluant.

      • by fnj ( 64210 )

        Or, expressed more rationally and clearly, 1 ng * g^-1 = 1 ppbm (part per billion by mass).

    • dw is dry weight (as opposed to lw, which is lipid weight), Apparently the two are highly correlated, but not strictly related.

  • Dump our waste that will remain for all eternity into the area on our planet that we understand the least, and in case we fuck up, we have no way to undo it.

    Is it me or does this sound like a really bad idea?

    • Dump our waste that will remain for all eternity into the area on our planet that we understand the least, and in case we fuck up, we have no way to undo it.

      You're actually not allowed to dump the waste into the ocean. And even China outlawed production of PCBs in the 1970s, although there's a question there — PCBs are cheaper to produce than any other kind of transformer oil, so is it actually still happening in secret? Inquiring minds.

      • by dbIII ( 701233 )
        Maybe, but there was a lot of it made and it lasts. I came across some stored at an old substation in the late 1980s and it's probably still there unless someone poured it down the drain (not unlikely).
    • I'm pretty sure you misinterpreted what the author suggested. I don't think they were suggesting that we 'should' dump waste in the oceans; rather that the food chain and other natural processes create a 'dead end' for the pollutants in the deep sea, which is where they're trapped and accumulate indefinitely.
  • When the PCBs ceased production, the 750,000 transformers containing PCBs were subsequently discarded as useless in the years 1980 to 1990.

    Currently, most of them are being dumped and sealed in caves or in cellars [tabemono.info]. However, due to the long term storage, the rotting process and other damages, PCBs leakages occurred. The soil surrounding the dumping site has been found to have a higher content of PCBs.

    Although, we can't blame it all on lax Chinese cleanup processes. We can probably blame the rest on maritime [epa.gov]

    • Why focus on China - Chinese PCB total production compares as just 2% of US production, and 4% of European production and less than 1% of total PCB production overall, with many unlicensed factories producing in eastern Europe after WW2. As mass production generally started in the 1930s in the US and Europe, where did all that early stuff go...?

      • Why focus on China

        Because as per my link, they have taken a typically Chinese approach to old PCBs and just thrown them into holes in the ground and pretended they didn't exist.

        • Yes, because US companies were so on the ball and utterly ethical in that area before the EPA came into being in the 1970s... or rather, who the fuck knows what happened to the hundreds of thousands of tonnes of PCBs manufacturered in the US between the 1930s and 1970s.

          It doesnt take much to list hundreds of sites where US companies took a "typically Chinese approach" to much worse chemicals than PCBs.

  • by OrangeTide ( 124937 ) on Tuesday February 14, 2017 @02:48AM (#53863761) Homepage Journal

    Many PCBs are stable in cold and dark conditions and need to be broken down by sunlight or the right kind of microorganisms. Without sunlight to break the chemicals down they are bound to persist for many decades and possibly centuries. In soil there are microorganisms that can break down PCBs, but they don't exist in the deep ocean (that I'm aware of).

    I suspect the concentrations to only increase over time, as rivers and lakes eventually get stable material from the bottom dredged from floods, construction or even drought. Resulting in more contaminates flooring into the ocean.

    Look, chemistry is a very powerful thing in nature. And we carry a huge burden of responsibility for the planet when we produce different chemical compounds on an industrial scale. There's nothing wrong with science and technology that can't be fixed with a little cautious restraint in how it is applied.

    "In all of your deliberations in the Confederate Council, in your efforts at law making, in all your official acts, self interest shall be cast into oblivion. Cast not over your shoulder behind you the warnings of the nephews and nieces should they chide you for any error or wrong you may do, but return to the way of the Great Law which is just and right. Look and listen for the welfare of the whole people and have always in view not only the present but also the coming generations, even those whose faces are yet beneath the surface of the ground -- the unborn of the future Nation." -- The Constitution of the Iroquois Nation (The Great Binding Law)

  • These are then consumed by amphipods and other deep sea creatures.

    So "fish" that eat "fish' have bad stuff in them, what's new? I regulate my tuna consumption because of the mercury buildup [wikipedia.org], and I love tuna. I would bet their mercury levels were high as well, but then that would not make news I suppose.

If I have not seen as far as others, it is because giants were standing on my shoulders. -- Hal Abelson

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