Plastic-Eating Worms May Cut Pollution

 

Researchers may have found an unusual way to reduce plastic pollution, one bite at a time.

It turns out that the common wax worm can eat plastic. Also known as the Galleria mellonella, these worms may help reduce the waste caused by plastic bags.

Each year, one trillion plastic bags are used around the world. They are made from polyethylene -- one of the strongest kinds of plastic.

The wax worm is the larvae¹, or young form, of an insect called the greater wax moth². These kinds of worms are also called caterpillars³.

Federica Bertocchini is with the Institute of Biomedicine and Biotechnology of Cantabria in Spain. She says researchers found that the larvae of the Galleria mellonella are able to biodegrade the plastic bags. To “biodegrade” means to break down by natural processes or bacteria.

Accidental discovery

They discovered this by accident, Bertocchini explains.

She says the plastic bags holding the wax worms “became riddled⁵ with holes.” In other words, the bags had holes all over them when the worms were inside.

Bertocchini, a beekeeper, says she made the chance discovery after removing the worms from beehives, where they live. She put the worms in a plastic shopping bag, which became full of holes.

Bertocchini worked with other researchers from the Spanish National Research Council and Britain’s University of Cambridge’s Department of Biochemistry. She carried out timed experiments on the worms.

She says the worms can “do damage to a plastic bag in less than an hour.” When 100 worms were placed in a normal British plastic shopping bag, the holes began to appear in just 40 minutes.

After 12 hours, researchers saw “an obvious reduction in plastic mass.”

They say a single enzyme⁶ produced by the worm is responsible for the chemical process that breaks down the plastic.

They also found that the worms turned the polyethylene into a different organic compound called ethylene glycol. It is used in making polyester fibers⁷ as well as antifreeze for vehicles. It is not clear if the worms produce enough for commercial use.

Plastic is not the worm's natural food

Plastic is not the natural food for the wax worm. But the researchers say that since they lay their eggs in beehives, the larvae feed on beeswax.

“Wax is a polymer, a sort of ‘natural plastic,’ that has a chemical structure that is not dissimilar to polyethylene,” Bertocchini says.

Researchers say they still need to better understand how wax is digested, or processed, in the worm. Finding that out could lead to a solution for dealing⁸ with plastic waste.

Bertocchini says they are planning to use this research to find a way to get rid of plastic waste. She says they are “working towards a solution to save our oceans, rivers and all the environment” from the problems of plastic waste.

But, she adds, we should not throw polyethylene into the environment, “just because we now know how to biodegrade it.”

The study was published in the journal Current Biology.

Words in This Story

biodegrade – v. to break down by natural processes or bacteria.

riddle⁴ – v. to make many holes in with something

obvious – adj. easy to notice or see

organic – adj. of, relating to, or obtained from living things

polymer – n. a chemical compound that is made of small molecules that are arranged in a simple repeating structure to form a larger molecule

1 larvae   

n.幼虫

参考例句：

• Larvae are parasitic on sheep.幼虫寄生在绵羊的身上。
• The larvae prey upon small aphids.这种幼虫以小蚜虫为食。

2 moth   

n.蛾，蛀虫

参考例句：

• A moth was fluttering round the lamp.有一只蛾子扑打着翅膀绕着灯飞。
• The sweater is moth-eaten.毛衣让蛀虫咬坏了。

3 caterpillars   

n.毛虫( caterpillar的名词复数 )；履带

参考例句：

• Caterpillars eat the young leaves of this plant. 毛毛虫吃这种植物的嫩叶。
• Caterpillars change into butterflies or moths. 毛虫能变成蝴蝶或蛾子。 来自辞典例句

4 riddle   

n.谜，谜语，粗筛；vt.解谜，给…出谜，筛，检查，鉴定，非难，充满于；vi.出谜

参考例句：

• The riddle couldn't be solved by the child.这个谜语孩子猜不出来。
• Her disappearance is a complete riddle.她的失踪完全是一个谜。

5 riddled   

adj.布满的；充斥的；泛滥的v.解谜，出谜题(riddle的过去分词形式)

参考例句：

• The beams are riddled with woodworm. 这些木梁被蛀虫蛀得都是洞。
• The bodies of the hostages were found riddled with bullets. 在人质的尸体上发现了很多弹孔。 来自《简明英汉词典》

6 enzyme   

n.酵素，酶

参考例句：

• Above a certain temperature,the enzyme molecule will become unfolded.超过一定温度，酶分子将会展开。
• An enzyme that dissolves the fibrin of blood clots.能溶解血凝块中的纤维的酶。

7 fibers   

光纤( fiber的名词复数 )； （织物的）质地； 纤维，纤维物质

参考例句：

• Thesolution of collagen-PVA was wet spined with the sodium sulfate as coagulant and collagen-PVA composite fibers were prepared. 在此基础上，以硫酸钠为凝固剂，对胶原-PVA共混溶液进行湿法纺丝，制备了胶原-PVA复合纤维。
• Sympathetic fibers are distributed to all regions of the heart. 交感神经纤维分布于心脏的所有部分。

8 dealing   

n.经商方法，待人态度

参考例句：

• This store has an excellent reputation for fair dealing.该商店因买卖公道而享有极高的声誉。
• His fair dealing earned our confidence.他的诚实的行为获得我们的信任。