Overview
A major analysis released by the Environmental Working Group (EWG) has found that 37 per cent of conventionally grown California produce contains PFAS pesticide residues. Out of 930 samples tested, 17 different PFAS compounds were detected across a range of fruit and vegetable crops. This research has significant implications for Australian environmental consultants assessing former agricultural land, particularly as urban expansion converts broadacre farming and orchard sites into residential subdivisions. The findings suggest that historical pesticide application may constitute a previously underestimated source of diffuse PFAS contamination in agricultural soils.
Key details
The EWG analysis tested conventionally grown produce from Californian farms, finding PFAS pesticide residues in more than a third of samples. The 17 detected PFAS compounds include substances used as active ingredients or adjuvants in agricultural pesticide formulations. Unlike industrial point-source PFAS contamination from manufacturing or firefighting foam use, this contamination pathway is diffuse, resulting from the repeated application of PFAS-containing pesticides over years or decades of agricultural use.
The study highlights that PFAS in pesticides is not limited to a single compound class. Multiple fluorinated substances were detected, reflecting the diversity of PFAS chemistry used in agricultural chemical formulations. Some of these substances are not routinely included in standard PFAS analytical suites used in Australian contaminated land assessments, potentially leading to false negatives in site investigations.
The contamination mechanism is direct: pesticides containing PFAS are applied to crops and soil. While some PFAS will be taken up by plants or degrade on the surface, a proportion accumulates in topsoil. Over decades of repeated application, this can build to concentrations that are environmentally significant, even if individual applications were within approved rates.
Australian context
Under the National Environment Protection (Assessment of Site Contamination) Measure 2013 (NEPM), Schedule B2 requires the development of conceptual site models that identify all potential historical sources of contamination. For sites with a long history of intensive agriculture, such as orchards, vineyards or broadacre cropping, omitting PFAS from the initial analytical schedule may no longer be defensible in light of this research.
The PFAS National Environmental Management Plan (NEMP 3.0) provides specific guidance on assessing diffuse source contamination and establishing background concentrations. However, current practice in Australia typically associates PFAS contamination with industrial sources, defence sites and firefighting training areas. Agricultural PFAS sources are rarely considered during the preliminary site investigation phase.
As Australian cities expand, large tracts of former agricultural land in areas such as Western Sydney, South East Queensland, the Barossa Valley and the Mornington Peninsula are being rezoned for residential development. Understanding the PFAS baseline of these sites is essential. Finding low-level, widespread PFAS across a proposed residential development late in the planning stage can significantly affect soil disposal strategies, development timelines and project economics.
The Australian Pesticides and Veterinary Medicines Authority (APVMA) regulates pesticide use in Australia. While the APVMA has taken some action on PFAS-containing pesticides, the historical application of these products means that legacy residues will persist in agricultural soils regardless of current regulatory settings.
Practical implications
- Environmental consultants should ask better questions about historical pesticide application during the desktop review phase of site investigations on former agricultural land.
- Preliminary site investigation scoping for former agricultural sites should consider including PFAS in the initial analytical suite, particularly where the site has a history of intensive horticulture or broadacre cropping.
- Developers acquiring former agricultural land for residential subdivision should factor PFAS screening costs into their due diligence budgets.
- Risk assessors should consider whether standard PFAS analytical suites adequately capture the range of fluorinated pesticide compounds identified in the EWG study.
- Soil disposal strategies for development sites on former agricultural land may need to account for low-level PFAS contamination, which can significantly increase disposal costs if concentrations exceed landfill acceptance criteria.
References and related sources
Original source: Environmental Working Group
Source published: 16 March 2026
Added to Enviro News: 16 March 2026
Read the primary source article at the Environmental Working Group
How iEnvi can help
iEnvi provides specialist contaminated land assessment services for agricultural land being rezoned for development. Our team conducts comprehensive PFAS site investigations, including assessment of diffuse source contamination, and prepares human health and ecological risk assessments. We assist developers and planning authorities with remediation strategies and soil management plans that address PFAS contamination early in the development process.
This is an iEnvi Machete news summary. Prepared by iEnvi to summarise the source article for contaminated land, groundwater, remediation, approvals and site risk professionals.
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