New evidence of particles damaging crops strengthens the case for an international plastics treaty
By The Guardian Editorial
New and concerning findings from environmental scientists about the impact of microplastics on crops and marine algae add to a growing body of evidence about the disruption caused to living systems by plastic pollution. The results, from a team led by Nanjing University professor Zhong Huan (鍾寰), are not definitive and require corroboration. However, analysis showing that plastics could limit photosynthesis (the conversion of sunlight into chemical energy) must be taken seriously. If the researchers are correct, and staple crops are being reduced by about 12 percent, there are huge implications for global agriculture and food supplies. That could inject new urgency into efforts to tackle plastic pollution.
There is no single route by which microplastic particles inhibit plants from growing. The overall effect is attributed to a combination of blocked sunlight and nutrients, and damage to soil and cells. That can lead to reduced levels of chlorophyll — the pigment enabling photosynthesis. When the researchers modeled the crop losses caused by an effect of that size, they found Asia was hardest hit, potentially contributing to food insecurity and worsening hunger.
The extent of the contamination of the Earth by microplastics has been widely documented. The tiny particles that are formed when plastics break down in the environment have been found in human semen, breast milk, brains, livers and bone marrow, and in remote areas, including the Arctic seas. The more than 500 million tonnes of plastics produced annually, most of which are dumped rather than recycled, leave their mark everywhere. Plastic is already understood to pose serious hazards to animals, including sea creatures, which can be poisoned and injured by it. It also ruins landscapes, with serious implications for the people who live in them and anyone trying to make a living from tourism.
However, there is still much to learn about the less obvious forms of damage caused by plastic pollution to humans and ecoystems. Links to strokes, heart attacks and preterm births are all cause for concern. One new study, presented at a conference in January, found that microplastic pollution was 50 percent higher in the placentas of babies born prematurely.
Talks in South Korea aimed at agreeing to a UN treaty on plastic pollution ended in failure in December last year. Almost all single-use plastics are made from fossil fuels, and fossil-fuel states and businesses oppose any limits on production. Record numbers of industry representatives at the summit meant that lobbyists outnumbered those attending for European governments. Perhaps as a result, although more than 100 countries supported a draft text including legally-binding reductions and the phase-out of some substances, no final deal was reached.
When talks reconvene in Switzerland later this year, those states must turn up with a plan. Under US President Donald Trump, the US is likely to ally itself with Russia and Saudi Arabia, meaning that making a deal would be even harder this time around. However, the enormous volume of plastic waste and the growing evidence of the range of harms it causes, mean action must be taken. Plastic would continue to have its uses, but the proliferation of single-use items, including packaging, is out of control. Just 9 percent of plastic gets recycled — and the recycling process itself can increase toxicity.
Fossil-fuel interests must be confronted over plastic pollution, just as they are challenged over global heating caused by coal, oil and gas.