评论
打印
Plastic as we know it has only been widely used since Tupperware was invented in the 1940s,
自从20世纪40年代发明了特百惠后，塑料才开始被广泛使用，
but now it's nearly impossible to go a day without it. And as useful as it is, plastic also causes some serious problems.
但是现在几乎一天都离不开它。尽管塑料用处很多，但它也造成了一些严重的问题。
You've heard about these things, turtles caught in six-pack rings, garbage patches as large as Texas,
大家或许听说过，乌龟卡在了六罐塑料环中，堆积起来的垃圾袋和德州一样大，
and beaches with more plastic debris than sand. After all, millions of tons of plastic end up in our oceans every year.
海滩上的塑料垃圾比沙子还多。毕竟，每年有数百万吨塑料流入我们的海洋。
But as bad as that sounds, some other consequences of plastic pollution might still surprise you.
听起来很糟糕，但塑料污染所造成的其他一些后果可能仍然会让你感到惊讶。
For one, plastics can emit greenhouse gases basically forever— not just during the making and disposing of them.
首先，塑料可以永久性地排放温室气体，而不仅仅是在其制造和处理过程中。
Plastic is basically just a long chain of molecules, and when it's exposed to sunlight,
塑料基本上就是一长串分子链，当它暴露在阳光下时，
UV radiation starts to break that chain down into smaller molecules like methane and ethylene, in a process called off-gassing.
紫外线辐射开始将这条分子链分解成更小的分子，比如甲烷和乙烯，这个过程被称为释气。
Both of these are greenhouse gases, but methane is especially bad because it's 25 times better at trapping heat at our atmosphere than carbon dioxide.
但是这些都是温室气体，但是甲烷尤其糟糕，因为它在大气中吸收热量的能力是二氧化碳的25倍。
And as plastic breaks down, the problem actually gets worse, not better.
随着塑料的分解，这个问题会越来越糟糕。
Researchers have found that, as more surfaces get exposed, there's a huge increase in the release of gases.
研究人员发现，随着越来越多的表面暴露在外，气体的释放量会大幅增加。
For example, a common plastic called LDPE, or low-density polyethylene,
例如，一种常见塑料低密度聚乙烯（LDPE）
releases methane 488 times faster in a powdered form than in pellet form.
粉末状的LDPE释放甲烷的速度是颗粒状的488倍。
To make matters worse, once this off-gassing process begins, it can continue even without sunlight.
让事情变得更糟糕的是，一旦释气过程开始，它甚至可以在没有阳光的情况下继续进行。
That's because those first broken bonds make the rest of the plastic more brittle, so it more easily breaks down on its own.
这是因为第一批断裂的化学键使其余的塑料更加脆弱，所以它更容易自行断裂。
Over time, it keeps breaking into smaller and smaller, eventually invisible, particles.
随着时间的推移，它不断地分裂成越来越小，最终成为看不见的粒子。
And as it does, it releases greenhouse gases into the air. Unfortunately, that's not the end of the story.
确实如此，它会向空气中释放温室气体。但还不止这样。
These indestructible pieces of plastic are also contributing to another modern problem: antibiotic resistance.
塑料中的这些坚不可摧的碎片也造成了另一个现代问题：抗菌素耐药性。
In a 2020 study out of Northern Ireland, scientists collected bacteria from plastic found along the Irish coastline
在一项于2020年在北爱尔兰进行的研究中，科学家们从爱尔兰海岸线发现的塑料中收集细菌
and tried to kill them with 10 commonly used antibiotics.... which turned out to be surprisingly hard to do.
并尝试用10种常用抗生素杀死这些细菌，结果很难杀死它们。
98% of the bacteria were resistant to ampicillin, one of the most commonly prescribed antibiotics for things like sinus and ear infections.
其中98%的细菌都对氨苄青霉素有耐药性，这是一种用于治疗鼻窦和耳朵感染的最常见抗生素。
And 16% of the bacteria were resistant to minocycline, another type of antibiotic.
并且其中16%的细菌都对另一种抗生素米诺环素有耐药性。
Unfortunately, plastic is a great breeding ground for bacteria, because they will grow on any available surface in the ocean.
不幸的是，塑料是细菌的滋生地，因为它们会在海洋的任何表面生长。
And many antibiotic-resistant bacteria are already out there—plastics just give them more places to flourish.
很多抗菌素耐药性细菌都在那里——塑料只是给了它们更多疯狂滋生的空间。
Once again, the problem gets worse as plastics break down, because they create even more surface area for bacteria to colonize.
一旦塑料分解，问题就会变得更糟糕，因为它们为细菌繁殖创造了更多的表面积。
And these bacteria don't just stay way out in the ocean.
而这些细菌并不只是停留在海洋深处。
The same study showed that ocean currents can carry plastic covered in bacteria back into coastal waterways,
同一项研究表明，洋流可以将被细菌覆盖的塑料带回到沿海水域，
where different species could ingest them.
在那里不同物种可以摄取它们。
Unfortunately, another 2020 study found that bacterial growth on marine plastics actually makes these plastics smell like food to sea turtles.
不幸的是，另一项2020年的研究发现，海洋塑料上的细菌生长使得这些塑料闻起来像海龟的食物。
So animals could be eating plastic because it smells good rather than because it looks like food. Which is not great.
所以动物们会吃塑料，因为塑料闻起来很香，而不是因为它看起来像食物。这就不太妙了。
Ingesting plastic covered in antibiotic-resistant bacteria could create health problems for marine animals—
吞食被抗菌素耐药性细菌覆盖的塑料会给海洋动物造成健康问题——
and also for creatures higher up the food chain, including us. Now, as plastic breaks down, it breaks into smaller and smaller and smaller pieces,
包括站在食物链高层的我们。现在，随着塑料的分解，它会分解成越来越小的碎片，
and some of the smallest plastics may be capable of doing the most harm. Any plastic that's smaller than a few micrometers is called a nanoparticle,
其中一些最小的塑料可能会造成最大的危害。任何比微米还小的塑料都被称为纳米颗粒，
and research has found that these microscopic particles can even pass through biological barriers, like cell membranes.
研究人员发现这些微小颗粒甚至可以穿过生物屏障，比如细胞膜。
That means they can enter the bloodstream of animals, pass through the gut lining, and penetrate tissues.
这意味着，它们可以进入动物血管，穿过肠道内膜，并穿透组织。
They can also accumulate in organs like the liver, kidneys, and intestines.
它们也可以在肝脏、肾脏和肠道等器官中聚集。
Plastic nanoparticles have even been found to penetrate the blood-brain barrier,
人们甚至发现塑料纳米颗粒可以穿透血脑屏障，
a layer of cells that filter harmful substances out of the blood so they can't get into the brain.
这是一层细胞，可以过滤血液中的有害物质，使它们无法进入大脑。
This seems to be dangerous no matter where you are on the food chain.
这似乎很危险，不论你在食物链的哪一层。
In a 2017 study out of Sweden, researchers exposed a zooplankton called Daphnia magna to a bunch of plastic nanoparticles.
在2017年瑞典的一项研究中，研究人员将一种名为大型溞的浮游动物暴露在一堆塑料纳米颗粒中。
The Daphnia consumed these particles, and scientists found that, while the larger particles didn't seem to affect them,
大型溞吃掉了这些颗粒，并且科学家们发现，虽然较大的颗粒似乎对它们没有什么影响，
the smallest particles —around 50 nanometers—were deadly. Next, to see the effect of the nanoparticles higher up in the food chain,
但最小的颗粒——约50纳米——是致命的。接下来，为了看看纳米颗粒在食物链更高层的影响，
they exposed a group of Daphnia to the plastic nanoparticles again, and then fed them to some fish called Crucian carp.
他们再次将水蚤暴露于塑料纳米颗粒中，然后把它们喂给一些鲫鱼吃。
Over the next two months, the carp started to change:
在接下来的两个月中，鱼开始改变：
They swam slower, explored less of their environment, and lost more weight than the control group.
与对照组相比，它们游得更慢，探索的环境更少，体重减轻的更多。
When the researchers analyzed the fish afterward, they found the 53-nanometer particles they had fed to the Daphnia were in the fish's brains.
当研究人员随后对鱼进行分析时，他们发现，他们喂给水蚤的53纳米颗粒存在于鱼的大脑中。
And they think these invisible particles changed the carp's behavior.
他们认为这些看不见的颗粒改变了这些鱼的行为。
These findings show that plastic nanoparticles can move up the food chain and interfere with the natural function of an ecosystem.
这些发现表明塑料纳米颗粒可以沿着食物链向上移动，干扰生态系统的自然功能。
And if we ate fish that had ingested nanoparticles, researchers suggest that could even have a direct impact on us.
如果我们吃了吞食过纳米颗粒的鱼，研究人员表示，这甚至会对人类造成直接影响。
Plastic is everywhere—in every environment in our planet— and it's not going away anytime soon.
塑料无处不在——存在于我们星球的每一个环境中——并且不会很快消失。
In some ways, that's great, because plastic can be really useful.
在某些方面，这很好，因为塑料真的很有用。
But unfortunately, it has some impacts that nobody was thinking about when they invented Tupperware.
但不幸的是，它存在着一些影响，这些影响是他们发明特百惠的时候所没想到的。
Still, the less plastic we use, and the more we understand the consequences, the better we can protect ourselves and our planet's natural ecosystems.
但我们使用的塑料越少，我们就越了解这些后果，我们就能够更好地保护自己以及我们星球上的自然生态系统。
Thanks for watching this episode of SciShow!
感谢收看本期节目。
And if you want to learn about ways to make this planet a better, less-polluted place,
如果你想了解更多保护地球减少污染的方法，
you might like our video about how engineers and research groups are working on ways to clean up our oceans. You can watch that right after this.
你或许会喜欢我们的视频——《工程师和研究团队何致力于清洁我们的海洋》。此处可观看。
