PFAS alert: EPA to test soil and crops irrigated with recycled water

An investigation has been launched into the accumulation of “forever” chemicals in soils and food crops irrigated with recycled water.

Crops and soils irrigated with recycled water from Melbourne Water’s western and eastern treatment plants are being investigated by the EPA for PFAS and other chemical contaminants.

Victoria’s Environmental Protection Authority has launched an investigation into contaminants in crops and soil irrigated with recycled water.

An EPA spokesman confirmed it was testing for chemicals as part of its investigation into “the uptake of emerging contaminants into soil and crops irrigated with recycled water”, with the results due to be publish in mid-2025.

The federal Department of Health says various studies have shown exposure to PFAS chemicals affect immune and hormone function, as well as being “associated with an increased risk of testicular and kidney cancer”.

Research dating back to 2018 has already shown irrigating crops with recycled water has led to low-level contamination of groundwater below Werribee South properties, detecting PFAS fluorinated alkyl chemicals in all samples.

The RMIT research team found the PFOS form of the chemicals “was the most detected compound overall (in 96 per cent of samples) with a mean concentration of 11 ng/L (ranging from 0.03 to 34 nanograms per litre)”.

Other RMIT research, conducted at the same time, found “low concentrations of PFAS contaminated soil (at 50 ng/kg) can affect plant biomass and growth in young plants”.

The nation’s peak Water Research Australia group has already set a PFOS concentration trigger of 22 ng/L for irrigating with recycled water, to protect stock feed and human food crops, based on 50 years of accumulated use.

One leading Werribee irrigator, who wished to remain anonymous, said the recycled water was “shandied with river water” and that both Southern Rural Water and Melbourne Water were regularly testing.

Victoria’s EPA has launched an investigation into PFAS and other contaminants in crops and soil irrigated with recycled water.

He also raised concerns over the potential impact of the PFAS debate on horticulture, given “it has the potential to get into the wrong hands and be misused”.

A Melbourne Water spokesman said PFAS tests on the Class A recycled water it supplies to growers “do not exceed the trigger points for investigation provided by Water Research Australia,” but failed to provide the results.

Melbourne Water and regional water authorities have also been sending biosolids to composting facilities and farms, which freedom of information documents show contain high PFOS levels.

The FoI documents, supplied to the Friends of the Earth environment group, show biosolids from Melbourne Water’s Eastern and Western treatment plants contain PFOS concentrations of about 50,000ng/kg, but range up to ten times that concentration.

In promoting the use of biosolids, Melbourne Water’s website states it has enough to fertilise “30,000ha of farm land, based on a re-application every 5 years in accordance with EPA guidelines”.

In the US concern over PFAS contamination has led the US state of Maine to ban the use of biosolids on crops and pastures, leading the state to set up a $90 million fund to assist farmers to deal with contamination.

In the meantime the public has until this Friday to comment on Australia’s National Health and Medical Research Council’s new drinking water guidelines for PFAS chemicals, which proposes slashing the allowable PFOS concentration from 70ng/L to just 4ng/L.

Adoption of the NHMRC guidelines will also force the Federal Department of Health to revise tolerable daily intake level of PFOS for humans, which currently sits of 20 nanograms per kilogram of body weight and 160ng/kg.bw for PFOAs.

WHAT THE UNITED STATES DEPARTMENT OF AGRICULTURE SAYS ABOUT PFAS.

PFAS is a class of man-made chemicals that have been manufactured and used in a variety of industries around the globe since the 1940s.

The chemical has been placed in the category of “forever chemicals’ because they bioaccumulate in animals and plants and do not breakdown naturally in the animals or plants or in the environment.

These chemicals in agricultural landscapes can cause food producers numerous challenges that require innovative scientific solutions from agriculture research, research and developments, and strategic partnerships.