‘Forever chemicals’ found in sewage sludge raises concerns

The UK farming sector is facing a growing concern over the spread of “forever chemicals”, on agricultural land through biosolids.

Investigations have revealed that contaminated sludge containing perfluoroctane sulfonate (PFOS), a particularly harmful type of per- and polyfluoroalkyl substances (PFAS), is being used as fertiliser.

PFAS are used in various products like cookware, cosmetics, and food packaging.

See also: British farmers undercut by lower pesticide standards

They are known for their inability to break down in the environment and are linked to various health issues, including cancers and hormone-related diseases.

A recent ENDS Report investigation revealed alarmingly high levels of PFOS in sewage sludge samples across England, particularly at a Thames Water-operated sewage treatment centre in Crawley, near Gatwick Airport, which recorded levels 135 times above the draft 1ppb safety threshold used in the US.

Despite these findings, no regulatory standard exists in the UK for PFAS levels in biosolids, and current regulations do not require water companies to test for them, focusing only on heavy metals and a few other chemicals.

Biosolids, a by-product of the sewage treatment process, are sold by water companies to farmers and are widely used in UK agriculture, with an estimated 3.5mt spread on farmland each year.

The potential for PFAS to bioaccumulate in the soil, crops, and livestock raises serious concerns about long-term contamination, as seen in places such as Maine, in the US, where farms have been forced to close due to high PFAS contamination from sludge.

Speaking at this week’s Labour Party conference in Liverpool, Defra’s water minister Emma Hardy expressed concern about the UK’s slow progress on restricting “forever chemicals” (PFAS), while other countries have taken action to ban them.

Contrasting views

The NFU has urged the sector “not to victimise” biosolids, while environmentalists, such as George Monbiot, have warned of a looming crisis if no action is taken.

Mr Monbiot is also one of three founders of campaign group Fighting Dirty, which last month lost a High Court challenge against the Environment Agency (EA) over its decision to axe a commitment to have sewage sludge tested for microplastics and forever chemicals before it is spread on agricultural land as fertiliser.

Defra and the EA say they are reviewing the regulatory framework for sludge and chemicals like PFAS, aiming to prevent further risks.