By Pawel Kidon, Technical Manager
Environmental, Australia & New Zealand
Considerations in per- and polyfluoroalkyl substances (PFAS) analysis continue to evolve.
In Aoteara / New Zealand, investigations of PFAS have progressed from initial source identification towards increasingly refined site characterisation and long-term management.
Early investigations were largely concerned with confirming presence and delineating primary source zones. Recent assessments, however, are asking more technically demanding questions with increasing granularity, foregrounding analytical detection capability as a growing interpretation requirement.
Under the Heads of EPAs of Australia and New Zealand’s (HEPA) PFAS National Environmental Management Plan (NEMP) 3.0, ultra-trace analyses may be considered for sensitive assessments or samples with low concentrations of PFAS. The method is defined here as achieving reporting limit lower than 99% species protection value, helping provide a baseline for defensible environmental decision-making.
Drivers for lower detection requirements and implications for site assessments
Detection requirements for PFAS are trending lower through regulatory compliance and increasingly stringent standards, with particular considerations for drinking water and public health protection. In New Zealand, the PFAS NEMP 3.0 outlines investigation and management best practices of PFAS contamination in the environment, including guidance on site assessment, sampling and laboratory analysis.
The New Zealand Te Mana Rauhī Taiao / Environmental Protection Authority (EPA) is the primary regulatory body overseeing hazardous substances management, including restrictions on PFAS-containing products. Recent regulatory measures have included the phase-out of PFAS in cosmetic products from 31 December 2026, reflecting a broader precautionary approach to long-term environmental and human health exposure.
Internationally, major drivers for lower analytical detection limits include:
- The US Environmental Protection Agency (EPA) established its first national Maximum Contaminant Levels (MCLs) in April 2024, including individual limits of 4.0 ng/L (ppt) for perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) and 10ng/L for other selected PFAS. These enforceable standards require routine monitoring at very low concentrations and have materially influenced laboratory reporting limits.
- The revised European Union Drinking Water Directive (DWD) 2020/2184, now in force, includes a parametric value for total PFAS (0.50 µg/L) and for the sum of selected PFAS (0.10 µg/L), requiring member states to implement monitoring programs with sufficiently sensitive analytical methods by early 2026.
- Australia’s National Health and Medical Research Council updated its Australian Drinking Water Guidelines (ADWG) on June 2025, reflecting lower revised health-based guideline values of 8ng/L for PFOS, 30ng/L for perfluorohexanesulfonic acid (PFHxS), 200ng/L for PFOA and 1000ng/L for perfluorobutanesulfonic acid (PFBS). These require analytical methods with sufficiently high sensitivity and validated performance at very low concentrations, placing greater emphasis on laboratories’ demonstrated low-level quantitation. capability.
In Aotearoa / New Zealand, the Water Services (Drinking Water Standards for New Zealand) Regulations 2022 establish maximum acceptable values (MAVs) for PFOS and PFOA in drinking water at 70ng/L, as well as regulating a total of 47 individual PFAS. These standards necessitate analytical methods capable of reliably quantifying PFAS at or below these thresholds, particularly where groundwater forms a source of potable supply.
Where reporting limits approach or exceed decision thresholds, the resulting dataset may constrain risk interpretation and compliance assessment. Ultra-trace methods address this limitation by extending quantitative capability into lower concentration ranges while maintaining precision, accuracy, and defined measurement uncertainty. For Aotearoa / New Zealand’s resource recovery, contaminated land and groundwater sectors, ultra-trace capability has several practical implications, including:
- Improved delineation of plume margins in groundwater investigations
- Greater confidence in distinguishing site-related impacts from regional background concentrations
- Enhanced resolution for long-term monitoring and trend analysis
- More robust verification of remediation endpoints and validation sampling
Analytical considerations at the ultra-trace level
The differences between current methods and ultra-trace level analysis require strict background control due to the extreme sensitivity required at sub-ppt concentrations. At these levels, laboratory-derived artefacts can be comparable to, or exceed, true environmental concentrations, necessitating enhanced contamination management and verification procedures.
PFAS analysis is undertaken by liquid chromatography tandem mass spectrometry (LC-MS/MS) with consideration of environmental contamination, using strict consumables to achieve reporting limits in the low ppt range.
Quality and sampling – the interplay between field and laboratories
Analytical capability at ultra-trace levels necessitates corresponding accuracy in field and sampling practices. Sampling equipment, container materials, personal protective equipment and transport conditions all influence contamination risk at very low concentrations.
These represent minimum QA/QC requirements for a PFAS sampling programme, consistent with the draft New Zealand Ministry for the Environment Sampling Protocols for PFAS (2018):
- Trip blank – a trip blank is collected to determine whether sample bottle preparation, transport and logistics, storage and handling procedures have impacted sample integrity.
- Equipment blank – also known as a rinsate blank, this is designed to verify the effectiveness of field equipment cleaning and decontamination procedures.
- Field blank – a field blank is collected to determine whether ambient site conditions or sampling activities have impacted on sample integrity.
In ultra-trace investigations, the frequency and interpretation of blanks require careful consideration, particularly where blank detections approach environmental sample concentrations.
Looking forward
Access to ultra-trace PFAS analysis within Aotearoa / New Zealand supports improved integration between environmental and contaminated land consultants and laboratories during method selection, sampling design and data interpretation. Local analytical capability helps reduce logistical complexity and holding-time risks associated with offshore testing, as well as strengthening our national technical resilience and capacity.
Ultra-trace PFAS testing represents an incremental, but significant advancement in understanding PFAS behaviour in groundwater and surface water systems. It reflects the broader trajectory of contaminated land practice toward lower tolerances, quantified uncertainty and increasingly defensible decision-making.
With the sector moving beyond binary questions of presence or absence, the shift of focus is now on precision, and how we can define concentrations and thresholds with greater confidence.
About Pawel Kidon
Pawel Kidon is a technical manager at ALS Environmental, Australia & New Zealand.
About ALS
ALS is a global leader in testing, providing comprehensive testing solutions to clients in a wide range of industries from contaminated land to resource recovery. Using state-of-the-art technologies and innovative methodologies, our dedicated teams deliver the highest-quality testing services and personalised solutions supported by local, site-specific expertise. We help our clients leverage the power of data-driven insights for a safer and healthier world.
Contact us today about selecting the optimal sub-ppt (ng/L) PFAS compound reporting suite to help support your project’s environmental and regulatory needs.
ALS Environmental Aotearoa / New Zealand
ALSEnviro.NZ@alsglobal.com