A cross-party group of MPs has warned that plastic piling up in British farm soil now threatens the country’s food supply, and is demanding legally binding limits to stop it at source.
The warning comes in a report from the All-Party Parliamentary Group on Microplastics, researched with the Women’s Institute and the University of Portsmouth after an inquiry that took evidence from 36 organisations. It found that UK farmland is among the most contaminated in Europe.
Our fields are being fed on treated sewage
Between 87 and 94 per cent of the 3.6 million tonnes of sewage sludge this country produces every year is spread on farmland as fertiliser. Plastic comes with it. Repeated spreading loads fields with an estimated 500 to 1,000 plastic particles per square metre a year, and one British study recorded microplastic levels in soil climbing by between 723 and 1,445 per cent after just four years of the practice.
Hardly anyone knows this is happening. A national poll found 61 per cent of people had no idea sewage sludge is routinely used on British farms. Farmers know. In a separate survey, 83 per cent recognised the threat from biosolids and 69 per cent were worried about what it is doing to their soil.
Soil is alive, and we are filling it with chemical cocktails
Professor Cressida Bowyer of the University of Portsmouth, senior author of the report, put it plainly. “Soil is not an inert material,” she said. “It’s a complex living ecosystem; it’s very finely balanced.”
Plastic particles change how soil holds water. They disturb the bacteria and fungi that keep it fertile. Earthworms that swallow them grow less and die sooner. The report warns that sludge spreading introduces microplastics at levels capable of jeopardising 95 per cent of soil life under current practice.
Then there is what the plastic carries. More than 16,000 chemicals are used in plastics. Just over a quarter are known to be hazardous. Six per cent are regulated. Bowyer said the particles “become like sponges or magnets for other things like bacteria, heavy metals”.
Ministers have managed one rule in nine years
The only regulation in Britain aimed squarely at microplastics is the 2017 ban on microbeads in cosmetics, which covers less than five per cent of what enters the environment. No targets. No limits. No deadlines. Meanwhile there were roughly 591,000 spills of untreated sewage in 2024.
Alberto Costa, the MP for South Leicestershire who chairs the group, said: “Existing measures tackle only a tiny proportion of microplastic emissions.”
The Women’s Institute got there first
WI members voted back in 2017 to raise the alarm about plastic pollution pouring out of household washing machines, and 170,000 of them have been campaigning on it since. France has already legislated for microfibre filters on new washing machines. The EU has set limits on microplastic discharges in wastewater. California monitors drinking water for the stuff.
The report asks for five things: legal reduction targets, regulation of the biggest polluting sources, producer responsibility for tyres, textiles and plastic pellets, proper permits and limits for sludge spread on land, and a national monitoring system so somebody is finally counting.
Dr Antaya March, who co-wrote the report, said: “We should not wait for every scientific uncertainty to be resolved before acting.”
Last November up to ten tonnes of plastic bio-beads escaped a Southern Water treatment works and washed up on Camber Sands. The first clean-up cost £2 million. There is still not a single law in this country saying those beads should never have been in our sea in the first place.