气候变化仅仅是地球遇到的挑战之一，我们所居住的星球还面临着堆积如山的垃圾和废弃物，尤其是白色垃圾。一项研究说，自1950年至今，人类已生产出83亿吨塑料制品，并尚未找到有效处理和回收塑料制品的方法。

Here's a staggering statistic. Scientists have calculated the total amount of plastic ever made: 8.3 billion tonnes. Looked at another way, that's as heavy as 25,000 Empire State Buildings or one billion elephants. And incredibly, almost all of it has been made in the last 65 years. 

So what's the problem? Much plastic is in the form of packaging which is used just once and then thrown away. According to a major new study from the University of California, 9% of this is recyled, 12% is incinerated and 79% goes to landfill. And because most plastic doesn't biodegrade, once it's in the ground, it stays there. 

It's a situation that has led the paper's lead author, ecologist Dr Roland Geyer, to say that we are "rapidly heading towards 'Planet Plastic'". He believes that there's already enough waste out there to cover the whole of Argentina.

The team behind this report also estimate that eight million tonnes of plastic waste are escaping into the sea every year. This has generated concern that plastic is entering the food chain, though fish and other sea life which ingest the smaller fragments.

Of course, the reason why there's so much plastic around is that it's an amazingly useful material. We can't get enough of it. It's durable and adaptable, and is used for everything from yoghurt pots to spaceships. But it's precisely this quality which makes it a problem. The only way to destroy plastic is to heat or burn it – although this has the side effect of harmful emissions.

So what's the alternative, other than using less plastic? Oceanographer Dr Erik van Sebille from Utrecht University says we're facing a "tsunami" of plastic waste, and that the global waste industry needs to "get its act together".

Professor Richard Thompson, a marine biologist from Plymouth University, says it's poor design that's at fault. He says that if products are currently designed "with recyclability in mind", they could be recyled around 20 times over.

Dr Geyer agrees: "The holy grail of recycling is to keep material in use and in the loop for ever if you can. But it turns out in our study that actually 90% of that material that did get recycled - which I think we calculated was 600 million tonnes - only got recycled once."