Final report 'PFAS research in organic and green waste Zwijndrecht'

22.06.2024 | Fundamental right

Final report 'PFAS research in organic and green waste Zwijndrecht'

Is there a risk of PFAS spreading through organic and green waste that is collected by the waste manager or brought to the container park? That was the question the municipal government of Zwijndrecht asked itself. OVAM conducted an exploratory study based on samples in the municipality in 2021 and 2022.

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In July 2021, green compost produced from green waste from the IBOGEM operating area was tested for the presence of PFAS. Three separate batches of green compost were sampled and analyzed separately. The total concentration of all measurable PFAS was 4.22, 0.97 and 3.52 μg/kg dry matter (DM), respectively.

It is striking that, just as with the investigated organic waste and green waste, PFBA, PFBS and PFOS were also measured slightly above the reporting limit in the green compost. The concentrations were lower due to the joint processing of green waste flows from other areas.

In the organic waste compost of the installation that processed organic waste from the IBOGEM operating area, very low concentrations of total PFAS were measured in three separate batches, namely 0.52, 0.61 and 0.59 μg/kg DS respectively. In 8 of the 9 determinations of PFBA, PFBS and PFOS, the values were below the reporting limit of 0.5 μg/kg DS.

The analysis results of the organic and green waste indicate an exceedance of the test value for PFAS in soil improvers. The PFAS compounds found can also be found in other environmental compartments within the study area, such as air, soil and groundwater. Although it is difficult to demonstrate a direct relationship between the concentrations in the waste and those in the various environmental compartments in this exploratory study, the route via falling dust is considered a plausible transfer path that requires further investigation.

As long as the vegetation in the study area is exposed to the inflow of PFAS compounds, the vegetation will remain burdened with these concentrations. This entails the risk that waste with excessively high PFAS concentrations will be further spread to other areas via the processing circuit. It is therefore necessary to periodically monitor the PFAS concentrations in the green waste, especially given the expected positive effects of the remediation of the sources of pollution in the vicinity of the study area.

Since 1 July 2022, a temporary framework for the use of waste materials as soil improvers has been in effect. This framework uses a test value of 15 μg/kg DS for PFAS-20, with which organic-biological waste, such as GFT and green waste, can be disposed of for composting. The research shows that there is a risk of exceeding this value in green waste within a radius of 1 km around 3M. The remediation measures, which have been introduced since the autumn of 2022, may possibly lead to a reduction in PFAS-20 concentrations in green waste. In addition, the remediation offers the opportunity to evaluate the “no regret” measures that currently apply to the management of GFT and green waste in the Zwijndrecht region.

The local authority and the appointed waste manager have the responsibility to manage the selectively collected household waste, such as green waste, in accordance with the environmentally responsible boundary conditions. In concrete terms, regular analyses of the green waste collected within the 1 km perimeter around 3M must demonstrate that the green waste meets the test value of 15 μg/kg DS before it can be offered for composting.