News | International
15 Oct 2019 12:44
NZCity News
NZCity CalculatorReturn to NZCity

  • Start Page
  • Personalise
  • Sport
  • Weather
  • Finance
  • Shopping
  • Jobs
  • Horoscopes
  • Lotto Results
  • Photo Gallery
  • Site Gallery
  • TVNow
  • Dating
  • SearchNZ
  • NZSearch
  • RugbyLeague
  • Make Home
  • About NZCity
  • Contact NZCity
  • Your Privacy
  • Advertising
  • Login
  • Join for Free

  •   Home > News > International

    Microplastics are probably in your diet. But should you be worried?

    A study of eight healthy Europeans adults found microplastics in all of their stool samples. But science is racing to catch up with the potential health impacts of the emerging issue.

    You've probably got microplastics in your poo.

    They were found in the stool samples of all eight participants of a study published last week in the Annals of Internal Medicine.

    The eight healthy adults from Europe, Russia and Japan had between 18 and 172 microplastic particles in their faeces, withnine different types of plastic recorded overall.

    Andit's not the first study to confirm that most of us are probably ingesting plastic semi-regularly.

    The question is, should we be worried?

    Where does it come from?

    Previous research has foundthe most common ways we take in microplastics are via airborne particles, shellfish, tap water, and even more so from bottled water,which contains an average of between 118 and 325 microplastic particles per litre.

    "Bottled water may be a strong contributor to microplastic ingestion," the authorswrote.

    "A total of 90,000 microplastic [particles would be consumed] annually if the person's recommended water intake comes entirely from bottled sources."

    Table salt is another big source, according to Thava Palanisami from the University of Newcastle, who wasn't involved in the latest study.

    "You're evaporating the salt from the sea water and the seawater contains microplastics," Dr Palanisami said.

    His research, yet to be peer-reviewed, found we could be eating up to 5 grams of microplastics each week.

    And because there's a lot of microplastics in seawater, that means sea creatures like fish, shellfish, and krill are absorbing them too.

    As bigger animals eat the smaller ones, you get a process of "trophic accumulation", where the amount of microplastics increases in animals up the food chain.

    What does it do to animals?

    We know that larger plastics hurt animals directly. Turtles choke on plastic bags and whales have been found with kilos of plastic waste in their stomach.

    The stomachs of thousands of seabirds on Australia's Lord Howe Island last year were found to be so full of plastics and microplastics that there was no room left for food.

    But microplastics are classified as less than 5mm wide, and aren't a choking hazard for larger animals.

    The issue is that microplastics can leach potentially disruptive chemicals into the body after they've been eaten.

    And while we might think that plastics that have weathered for a long time in the environment have leached outmost of their chemicals already, that's not always the case.

    "Chemicals can leach out in the environment, but [they] can also increase during weathering — plastic can absorb chemicals from the environment," Dr Palanisami said.

    In research published last week, scientists added three different types of microplastics (including plastics from clothing fibres) to soil and then added earthworms and planted ryegrass in it.

    They found the worms in the microplastic soil were smaller than the control plots, and the ryegrass-shoot height was smaller than in the control as well.

    Other research has found microplastics disrupt photosynthesis in marine bacteria and that they can act as potential vectors for microbes with antibiotic resistant genes.

    How do we study humans?

    Because this is stillan emerging field of research, there is a lot that is unknown about what impacts microplastics may have on the ecosystem, according to Jennifer Lavers from the University of Tasmania.

    While small animals like sea-cucumbers and aquarium fish are easily kept in labs, it's much more difficult for researchers to get long-term data for bigger species.

    "If you want to monitor the impact of plastics or chemicals on an animal over time, you need to be able to capture and study that animal many, many times," Dr Lavers said.

    "So say tuna — you can catch that tuna once, but how are you going to catch a tuna many times?

    "Then if you think of something like a blue whale or a humpback whale, it's just not going to happen."

    Instead, researchers are limited to studying the impacts on smaller animals, and can only assume that the same mechanisms apply to larger ones.

    And the same goes for humans. For us, there's even less data on the potential health effects of microplastics.

    That's partly because the field of research is new, and because we can't ethically give people doses of microplastics to see what happens.

    So what do we know?

    In the latest paper, the authors conclude that "further research on the extent of microplastic intake and the potential effect on human health is needed".

    The fact that microplastics were detected in human faeces in the study suggests that they're passing through the body.

    But it's what happens when they'reinside usthat is unknown.

    Bisphenol A (BPA) in plastics is one of a number of compounds that poses potential health risks, according to Dr Palanisami.

    "BPA was considered a potential carcinogen. And then phthalates — they can be endocrine disruptors," he said.

    "There are a few more chemicals too — there's actually about 10 chemicals [in plastics] that can have an effect on human health."

    Like anything though, the dose makes the poison.

    And the amount we actually absorb is probably very low, according to a World Health Organisation (WHO) report from last month.

    "Microplastics larger than 150 micrometres (a micrometre is a millionth of a metre) are unlikely to be absorbed in the human body, while the uptake of smaller particles is likely to be limited," the report stated.

    "Based on the limited information we have, microplastics in drinking water don't appear to pose a health risk at current levels."

    However, the report concedes that the absorption of nano-sized [a thousandth of a micrometre] particles may be higher.

    WHO Director Maria Neira said finding out more about the potential impacts is a top priority.

    "We urgently to know more about the health impact of microplastics because they are everywhere," Dr Neira said.

    © 2019 ABC Australian Broadcasting Corporation. All rights reserved

     Other International News
     15 Oct: ICC changes boundary countback rule that decided Cricket World Cup final in England's favour
     15 Oct: Donald Trump's Republican support is cracking, and impeachment will reveal his real base
     15 Oct: Queen's Speech used to reiterate Britain's commitment to Brexit deadline on October 31
     15 Oct: Newborn baby girl pulled from shallow grave in India, survives in hospital
     14 Oct: Humans put 100 times more carbon into the atmosphere than volcanoes, but that's just the tip of the iceberg
     13 Oct: El Camino's Breaking Bad cameos, Easter eggs and remaining questions explained
     13 Oct: Honey bees perform better at a maths task with the right training
     Top Stories

    All Blacks and Chiefs flanker Sam Cane has paid tribute to the leadership of Japan captain Michael Leitch at the rugby World Cup More...

    Westpac is predicting house prices will rise by up to seven per cent next year More...

     Today's News

    Westpac is predicting house prices will rise by up to seven per cent next year 12:27

    Duchess Catherine accompanied her younger brother James Middleton to therapy 12:22

    The dream of an England football debut has been tarnished for Tyrone Mings 12:07

    ICC changes boundary countback rule that decided Cricket World Cup final in England's favour 12:07

    Law and Order:
    Police have arrested two people in Cromwell - as they try to stamp out meth in Otago 11:57

    Liam Hemsworth is "taking it slow" with Maddison Brown 11:52

    Stacey Solomon felt "really anxious" at the thought of going out with her baby son 11:22

    Law and Order:
    The Police watchdog has found an officer involved in a crash with a fleeing driver, broke the rules 11:07

    Sir Elton John had to learn to "become a human being again" when he got sober 10:52

    An economist doubts proposed Kiwisaver changes will have the desired effect 10:47

     News Search

    Power Search

    © 2019 New Zealand City Ltd