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【○隻字片羽○雪泥鴻爪○】



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既然有緣到此一訪,
何妨放鬆一下妳(你)的心緒,
歇一歇妳(你)的腳步,
讓我陪妳(你)喝一杯香醇的咖啡吧!

這裡是一個完全開放的交心空間,
躺在綠意漾然的草原上,望著晴空的藍天,
白雲和微風嬉鬧著,無拘無束的赤著腳,
可以輕輕鬆鬆的道出心中情。

天馬行空的釋放著胸懷,緊緊擁抱著彼此的情緒。
共同分享著彼此悲歡離合的酸甜苦辣。
互相激勵,互相撫慰,互相提攜,
一齊向前邁進。

也因為有妳(你)的來訪,我們認識了。
請讓我能擁有機會回拜於妳(你)空間的機會。
謝謝妳(你)!

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2022年7月1日 星期五

Microplastics in the food chain: How harmful are they?


Microplastics in the food chain: How harmful are they?

Researchers are studying the impact of microplastics on human health.

Image: REUTERS/Eric Gaillard

  • Microplastics are pieces of plastic debris under five millimetres in length.
  • Research suggests they could end up in the human food chain through a variety of sources.
  • Studies are ongoing about the potential impact on human health.

There's a growing body of evidence about how widespread microplastics have become, across landsea and air.

In 2019, researchers found that we consume thousands of these plastic particles every year, while further research published in May 2022 found the presence of microplastics in human blood.

But the problem isn't new. The UN Environment Programme explains that plastics - for example, microbeads - have been used in cosmetics and toiletry products for more than half a century.

Indeed, in 2015, US President Barack Obama banned the use of such microbeads in personal care and cosmetic products.

What are microplastics?

Microplastics are pieces of plastic debris under five millimetres in length, explains the US National Ocean Service.

Some - such as the microbeads mentioned above - are designed to be this small, while other plastic gradually breaks down to this size.

'If you eat muscles, you eat microplastics.' Image: Our World in Data

How do they get into the food chain?

These tiny particles are often small enough to make it through water filtration systems. From here they can end up in the ocean and other water systems.

Equally, research has suggested that such microplastics can be transported in the atmosphere, spreading themselves into even some of the remotest corners of the Earth.

In the ocean, these particles can be eaten by marine life - from fish to shellfish. And, although Food Standards Australia and New Zealand says that ingestion is much less likely while eating finfish, exposure from shellfish could be higher.

Indeed, a study earlier this year found broken-down microplastics in blue mussels off the Australian coast. Researchers warned that the finding means that microplastics are ending up in human food supplies.

“By investigating microplastic load in the mussel, we call attention to the implications of microplastic pollution on South Australia’s unique marine ecosystems and on the local human food chain,” said lead author Janet Klein. The research added to the findings of an earlier study that concluded, 'if you eat muscles, you eat microplastics'.

Various microplastic particles found in water samples. Image: Flinders University

And it's not just marine life that could be affected. The Guardian reports that microplastics have been found in foodstuffs including honey, tea and sugar, while Greenpeace warns they could be found in fruit and vegetables and salt.

Are microplastics harmful to human health?

It's still unclear what the environmental and health impacts of microplastics could be, according to a news release from the American Chemical Society.

Indeed, as Prof Mark Taylor of Macquarie University in Sydney told The Guardian last year, "nobody really knows". However, as he stressed, "absence of evidence is not evidence of absence".

But, there's research ongoing, according to the American Chemical Society, although lots more work is needed if we're to understand the effects. A Nature news feature in May 2021 explained that the first step underway at the moment is understanding levels of exposure.

For example, in California, work is underway to test and report levels of microplastics in drinking water.

What's being done about it?

In addition to regulation, for example in the US, there are some more eye-catching approaches too.

For example, a team of researchers at Sichuan University has developed a tiny robot fish that can collect microplastics.

And, last year, the BBC reported on a removal method using vegetable oil, iron oxide and magnets. Following 5,000 tests, the method was found to be 87% effective at extracting microplastics from water.

DISCOVER

What is the World Economic Forum doing about plastic pollution?

License and Republishing

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The views expressed in this article are those of the author alone and not the World Economic Forum.

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