EWG Report on PFAS in Agricultural Pesticides

Overview

A major analysis from the Environmental Working Group (EWG) has revealed that 37 per cent of conventionally grown California produce contains PFAS pesticide residues. Out of 930 samples tested by the United States Department of Agriculture, 17 different PFAS residues were detected across a wide range of fruit and vegetable crops. The findings raise serious questions about the extent to which per- and polyfluoroalkyl substances have entered the agricultural supply chain through pesticide formulations, and what this means for land contamination assessments worldwide.

For Australian environmental consultants, site auditors and contaminated land professionals, this report has immediate practical relevance. It suggests that former agricultural land may carry a PFAS legacy that has nothing to do with firefighting foam or industrial discharge. Instead, decades of routine pesticide application could have introduced PFAS compounds into topsoil, with implications for site investigations, soil disposal classifications and residential redevelopment planning.

Key details

The EWG analysis focused on produce samples collected through USDA testing programs. The 17 PFAS residues identified included compounds used as active ingredients or adjuvants in registered pesticide products. Among the crops most frequently affected were leafy greens, strawberries and stone fruit. The contamination was not limited to a single compound class but spanned both legacy and emerging PFAS chemistries.

The critical finding for contaminated land professionals is the diffuse nature of this contamination pathway. Unlike point-source PFAS releases from industrial facilities or firefighting training grounds, agricultural PFAS contamination is distributed across entire paddocks and orchards. This diffuse distribution creates challenges for delineation, as contamination may be relatively uniform across large areas rather than concentrated in identifiable hotspots.

The study also noted that organic produce showed significantly lower PFAS detection rates, reinforcing the link between conventional pesticide use and PFAS accumulation in soil and plant tissue.

Australian context

Under the National Environment Protection (Assessment of Site Contamination) Measure 2013 (NEPM 2013), Schedule B2 requires the development of robust Conceptual Site Models (CSMs) that identify all potential historical sources of contamination. If a site has a long history of intensive agriculture, such as orchards, vineyards, market gardens or broadacre cropping, the omission of PFAS from the initial analytical suite may no longer be defensible.

The PFAS National Environmental Management Plan (NEMP 3.0) provides specific guidance on assessing diffuse source contamination and establishing background concentrations. Australian regulators have increasingly recognised that PFAS contamination extends well beyond defence bases and airports. The EWG findings add another source category that must be considered during desktop reviews.

This is particularly relevant as urban expansion across Sydney, Melbourne, Brisbane and South East Queensland converts former agricultural land into residential subdivisions. Finding low-level, widespread PFAS across a proposed residential development site late in the planning stage can significantly affect soil disposal strategies, development timelines and project costs. Soil classified as containing PFAS above landfill acceptance criteria may require treatment or disposal at licensed facilities, adding substantial expense to civil works budgets.

Australian states including New South Wales, Queensland and Victoria each have their own PFAS investigation guidelines that complement the NEMP. Consultants must ensure their desktop studies ask the right questions about historical pesticide application, crop types and application methods during the preliminary site investigation phase.

Practical implications

For site assessors and environmental consultants, this research suggests several practical changes to standard practice:

• Desktop reviews: Historical land use assessments for former agricultural properties should now specifically investigate pesticide application records, crop types and application frequencies. Title searches and aerial photograph reviews should be supplemented with enquiries about chemical storage areas and mixing locations.
• Analytical programs: Where a site has a documented agricultural history spanning decades, PFAS should be included in the preliminary investigation analytical suite alongside the standard suite of organochlorine and organophosphate pesticides, metals and nutrients.
• Conceptual Site Models: CSMs for former agricultural sites should include the pesticide-to-soil-to-groundwater pathway for PFAS, even where no other PFAS source has been identified. This pathway should also consider lateral migration through shallow groundwater systems.
• Soil disposal: Developers and civil contractors working on former agricultural land should factor PFAS testing into early-stage soil characterisation programs to avoid unexpected disposal costs during bulk earthworks.
• Regulatory engagement: Where low-level, diffuse PFAS is identified on former agricultural land, early engagement with the relevant state EPA is advisable to agree on an appropriate assessment and management framework.

References and related sources

• EWG: Forever chemicals contaminate nearly 40% of non-organic California-grown produce
• Australian Government PFAS information and guidance
• NEPM 2013 – Assessment of Site Contamination
• PFAS National Environmental Management Plan (NEMP)

How iEnvi can help

iEnvi provides specialist contaminated land assessment services across Australia, including PFAS investigations on former agricultural properties. Our team conducts desktop reviews, develops fit-for-purpose Conceptual Site Models and designs analytical programs that account for emerging contaminant pathways. Whether you are a developer assessing a greenfield site with agricultural history or a local council managing legacy contamination, iEnvi can deliver the technical guidance you need. We also provide remediation planning and management for PFAS-impacted sites, from options assessment through to validation.

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.

Need advice on this topic? Speak to an iEnvi expert at hello@ienvi.com.au or 1300 043 684, or contact us online.