塑料袋，想说恨你不容易

By Ross Clark

Its not hard to see why everyones worried about plastic. The seas are unquestionably heavily polluted with plastic， as are some rivers and streams. Frans Timmermans， vice-president of the European Commission1， recently declared war on“single-use plastics that take five seconds to produce， are used for five minutes， then take 500 years to break down again.” Its utterly depressing to think that plastic bags， yoghurt pots and disposable cups will be the chief archaeological2 relics of our age.

我們十分清楚塑料袋对于环境的危害：生产一个塑料袋只需要五秒钟，但是自然降解一个塑料袋却要花上五百年。抵制一次性塑料制品成为许多国家流行的环保政策。但是在这种狂热抵制的背后，我们忽视了许多更为复杂的问题：塑料制品的替代品真的更加环保吗？对塑料袋征税真的能起到保护环境的作用吗？又有什么更好的政策能鼓励人们主动回收利用塑料制品呢？

But when public opinion is so much in agreement on an issue， we should all be on our guard. Its exactly when everyone agrees about an issue that bad decisions are made， some with awful and far-reaching unintended consequences.

The trouble with the new plastic obsession is the same trouble we had with carbon emissions 20 years ago. Environmental policy becomes so focused on one specific， fashionable problem that no one notices that the proposed solutions are， in other ways， making matters worse. In the case of carbon emissions， the Blair government3 （along with the European Commission） became so fixated in cutting the amount of CO2 that they encouraged motorists to switch to diesel—inadvertently sanctioning an increase in deadly nitrogen oxide emissions.4

This is the risk we now face with the war on plastic. If supermarkets follow through on their recent promises to ban plastic packaging， its a struggle to see how they will keep fruit and veg fresh for long. The very people weve tried so hard to encourage to eat well will revert back to Turkey Twizzlers. It is easy now to forget what shopping was like before supermarkets transformed the British diet in the 1970s， before chiller cabinets and the revolution in food packaging， to which the traditional seasonal shortage of fresh vegetables was eliminated owes a lot.

Youre only really entitled to feel virtuous about eschewing5 plastic if you look carefully into the effect on the environment of your chosen alternative. Take Goves coffee cup.6 There have already been rumblings7 about overharvesting of bamboo in Chinas Sichuan Province. There is more general concern， too， about the wide-scale use of plant-based alternatives to oil-derived plastics. As long as bioplastic remains a niche product for concerned middle classes，8 the land issue isnt important. If bioplastics are adopted across industry， it will be a genuine cause for concern.

According to a report on the environmental impact of bioplastics published by the government in 2010， it takes 1.7 square metres of arable land to grow each kg of PLA9， one of the main bioplastics， which can be used as a substitute for many types of food packaging. Europe consumes almost 60 million tonnes of plastic a year. If all this packaging were instead grown in fields， it would take up 40，000 square miles—nearly a tenth of all arable land currently under cultivation in Europe. And what about the carbon emissions from biodegradable10 plastics？ They tend to decompose straight to methane，11 a greenhouse gas measured to have 20 times the potency of CO2.

What is remarkable about the war against plastics is that hostilities were first started a decade and a half ago， but were stopped in their tracks by some powerful evidence. The plastic bag tax was first tried in Ireland in 2002， when a 15 cent charge per bag was similarly found to cut bag use by 90 per cent. If shoppers are going without any kind of bag and trying to balance numerous items in their hands， that can be counted as an environmental gain. But if they have switched to other types of bag then the benefits are harder to discern12. When a plastic bag tax was proposed in Scotland， the devolved13 government launched a two-year assessment comparing the“life-cycle analysis” of single-use plastic bags against paper bags. In 2005， it came to the surprising conclusion that a“paper bag has a more adverse impact than a plastic bag for most of the environmental issues considered”.

Six years later， Defra14 compared the environmental impact of plastic bags with its rivals. That study came to the remarkable conclusion that a cotton shopping bag would have to be used 173 times before it became responsible for fewer carbon emissions than a plastic bag—cotton being a very intensive crop requiring large amounts of water and fertiliser.

Single-use plastic bags also performed better environmentally than paper bags and biodegradable plastic bags and plastic “bags for life”. And this was assuming that “single-use” plastic bags are just that—when of course they are often used for other purposes， such as bin liners15. When Wales introduced its own 5p plastic bag levy16 seven years ago， it led to a 25 per cent surge in the sales of pedal bin liners—to replace the supermarket bags that people had previously been using. Moreover， the plastic bag levy has done nothing to counter the wasteful packing being used in online sales.

Surely， if we were going to have levies on bags， the evidence suggests that it ought to apply to all kinds of bags and all kinds of packaging. Yet the plastic bag levy went ahead anyway， as if no research had been conducted into the issue. Its just not in the interest of government to look into the full environmental impact of a widely popular plastic tax. We consumers care but were busy. We just dont really want to be told that our careful measures are actually counterproductive17.

We must do something to stop plastic bags， bottles and beads clogging up the sea. A better idea might be a waste disposal deposit on all such goods， a surcharge which could then be returned to whoever presented it for recycling. That would give all waste a value， providing an incentive for people to collect it. Would beaches be littered with plastic bags if enterprising18 children were picking them up in order to claim a deposit， just as in my youth kids used to do with lemonade bottles？

Policymaking does not always follow logic. On the environment in particular it tends to dart between fashionable issues， ignoring complexities. For aesthetic reasons， its hard to like plastic. That gives the drive to banish it from modern life its particular momentum19. But I suspect it wont be long before we feel the need to reinvent it.

不难理解为什么每个人都在担心塑料制品。海洋正毫无疑问地遭受着严重的塑料污染，河流和小溪也是如此。欧盟委员会副主席弗兰斯·蒂默曼斯最近向“生产只需五秒钟、使用只有五分钟，却要花上五百年来降解的一次性塑料制品”宣战。一想到塑料袋、酸奶瓶和一次性纸杯将会成为我们这个时代留给后人的主要考古遗迹，难免会令人十分沮丧。

但是当公众意见在某项议题上达成高度共识的时候，我们便应该保持警惕。正是当所有人在某一事务上意见统一的时候，人们反而容易作出不好的决定，有些决定还会产生糟糕、意料之外且影响深远的结果。

我们热衷于治理塑料制品所产生的问题，与20年前我们努力降低碳排放所导致的问题是一样的。环境政策过分集中于某一个具体、热门的问题，以至于人们注意不到这些问题的解决方案会在其他方面让事情变得更糟。在控制碳排放这个问题上，布莱尔担任首相时期的英国政府（以及欧盟委员会）在降低二氧化碳排放方面采取了十分死板的政策，以至于他们鼓励开车的人使用柴油——这在无意间导致了致命的氮氧化合物排放量的增长。

这就是目前我们所面对的向塑料制品宣战所带来的风险。如果超市兑现了它们近期作出的不再使用塑料包装的承诺，如何长时间保持果蔬新鲜便成为了一个不小的难题。我们费了很大力气劝导要健康饮食的那些人将会重新开始吃“扭扭火鸡肉”。现在几乎想象不出上世纪70年代在超市改变英国饮食习惯之前的购物是什么样子了。当时，冷冻柜进入超市以及食品包装革命的发生，都大大减少了当季新鲜蔬菜短缺的情况。

如果你仔细看清你选择的塑料制品替代品给环境造成的影响的话，那么你才真的有资格为不使用塑料制品而感到高尚。就拿迈克尔·戈夫所倡导的可重复使用的咖啡杯来说，现在已经有关于中国四川省的竹子被过度开采的不满言论了。此外，大规模地用植物性產品取代由石油提炼加工而成的塑料产品也是一个更为普遍的担忧。只要生物塑料依旧是中产阶级所关注的利基产品，土地问题的重要性就会被忽视。如果生物塑料在工业生产中被广泛使用，那么土地问题将会成为一个真正令人担忧的事情。

一份2010年政府发布的关于生物塑料对环境影响的报告显示，每生产一千克聚乳酸（一种主要的生物塑料，可以作为多种食物包装的替代），就需要1.7平方米的耕地。每年欧洲的塑料消费量接近六千万吨。如果这些需求只靠生物塑料来满足，那么则需要四万平方英里的土地——这大概是目前欧洲全部耕地面积的十分之一。此外，生物可降解性塑料所造成的碳排放量又在什么水平呢？它们会直接被分解为甲烷，这种气体加重温室效应的能力是二氧化碳的20倍。

这场与塑料制品的战争值得注意的一点是，对塑料的抵制首先是从15年前开始的，但是这一进程被一些有力的证据中断了。2002年，爱尔兰首次试行对塑料袋征税政策，每个塑料袋加收15分的税在当时也降低了90%的塑料袋使用量。如果人们在购物时不用袋子，而是直接用手拿着各种商品的话，这对环境是有利的。但是如果人们用其他东西代替塑料袋，对环境的好处则很难看出来。当塑料袋税在苏格兰被提出的时候，权力下放的苏格兰政府进行了一项为期两年的调查，将一次性塑料袋的生命周期与纸袋子的相比较。2005年，这个调查得出了一个出乎人们意料的结论：如果将大多数环境因素考虑在内的话，纸袋子产生的不利影响要比塑料袋多。

六年后，环境、食品和农村事务部比较了塑料袋及其替代品对环境造成的影响。这个研究得出了一个值得注意的结论：一个棉布袋只有被使用了173次以上，产生的碳排放量才会比塑料袋少——因为棉花是一种非常集约化的作物，需要大量的水和化肥。

在环保方面，一次性塑料袋也要比纸袋子、可生物降解性塑料袋和可重复使用的塑料袋要好。当然，这个结论的前提是——塑料袋也经常被拿来用在其他地方，比如当做垃圾袋。当威尔士在七年前开始对塑料袋征收五便士的税时，脚踏式垃圾桶衬袋的销量猛增了25%，用来代替人们之前所使用的超市塑料袋。此外，塑料袋税也没能减少人们网购所产生的即用即扔的塑料包装使用量。

所以必然地，如果我们要给袋子征税的话，所有类型的袋子和包装都应该被算在内。然而现在只有塑料袋被征税，就好像我们在这个问题上没有进行过研究一样。深入研究大受欢迎的塑料袋税对环境的各种影响并不只是为了政府的利益。我们消费者也很在意这件事，但是我们却很忙。我们只是不想看到，我们精心采取的环保措施竟会适得其反。

我们一定要采取措施，不让塑料袋、塑料瓶和塑料珠继续堵塞海洋。一个更好的方法是建立一个“废物处理储蓄金”，以作为额外费用回报那些将其回收利用的人。这样的话，垃圾废物也就有了价值，能够激励人们把它们收集起来。就像我小时候孩子们会回收柠檬水瓶子一样，如果有上进心的孩子们为了拿到一些零花钱，主动将海边的垃圾捡起来的话，我们的海滩还会到处都是塑料袋吗？

政策的制定并不总是遵循逻辑。尤其在环保问题上，它容易受到热门议题的影响而盲目求进，却忽视了其中的复杂性。塑料袋的确不符合美学，所以我们很难喜欢它。这个原因使得我们努力将它从现代生活驱逐出去。然而我觉得，用不了多久，我们就又要让它回归了。

1. European Commission： 欧盟委员会，简称欧委会，是欧盟的常设执行机构，欧盟中唯一具有起草法令权力的机构。

2. archaeological： 考古的。

3. Blair government： 布莱尔政府。托尼·布莱尔（Tony Blair），1997—2007年担任英国首相。

4. diesel： 柴油；inadvertently： 无意地，不经意地；sanction： 批准，许可；nitrogen oxide： 氮氧化物。

5. eschew： 避免。

6. Michael Gove： 迈克尔·戈夫，英国保守党政治家，曾任教育大臣（2010—2014）和司法大臣（2015—2016），2017年起出任环境、食物和农村事务大臣。这里是说他曾经把可重复使用的竹制咖啡杯作为礼物送给其他内阁大臣。

7. rumbling： [～s] 抱怨，不满的言论。

8. bioplastic： 生物塑料，是来自可再生的生物质来源的塑料，如植物油、玉米淀粉、微生物群等，能更好地进行生物降解；niche product： 利基产品。利基是针对企业的优势细分出来的市场，这个市场不大，且“有获取利益的基础”。

9. PLA： 聚乳酸（polylactic acid）的简称，是一种可再生生物降解材料，由可再生的植物资源（如玉米）所提取出的淀粉原料制成，是公认的环境友好型材料。

10. biodegradable： 可进行生物降解的。

11. decompose： 分解；methane： 甲烷。

12. discern：（尤指仔细思考或研究之后）看出，觉察出。

13. devolved： 权力下放的。20 世纪以来，苏格兰独立运动愈演愈烈，迫使英国中央政府将权力让渡给了苏格兰地方政府，“权力下放”成為当代英国政治发展的重要组成部分之一。

14. Defra： 全称是Department for Environment Food and Rural Affairs，英国环境、食品及农村事务部。

15. bin liner： 垃圾桶衬袋。liner意为“衬里”。

16. levy： 征税。

17. counterproductive： 事与愿违的，适得其反的。

18. enterprising： 有事业心的，有进取心的。

19. momentum： 动力，势头。