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Determining levels of PFAS chemicals in estuarine and coastal sediments - ME5234

PFAS (per- and polyfluorinated alkyl substances) is a family of potentially thousands of synthetic organic chemicals that are extremely persistent in the environment and have bioaccummulative and toxic properties. The group includes the water policy/regulated chemicals perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA).
The oil, water and stain repellent properties of PFAS mean they are used in a wide range of processes and products, including protective treatments e.g. waterproofing textiles and as surfactants e.g. in fire-fighting foams. However, there is now growing regulatory and academic concern regarding the exposure impact on people and wildlife of this group of chemicals. As such, PFAS are identified as emerging substances of high concern for chemical management.
Although PFAS have been detected in air, surface water, groundwater (including drinking water) and soil on an international scale, data on PFAS concentrations in the environment in England is very limited. PFOS is a priority hazardous substance in Annex I of the Priority Substances Directive (Directive 2013/39/EC) of the Water Framework Directive and has therefore received the most attention in environmental regulators’ monitoring programmes. The Environment Agency has a small amount of PFOS data in saline biota and water, alongside their freshwater monitoring data and data from the UK water industry’s Chemical Investigation Programme. Concentration levels in estuarine sediments however are unknown. There is a need to establish current PFAS levels in nearshore sediments so that pathways and risks to the marine environment can be better understood.
The project proposes to collect up to 80 sediment samples from a number of English estuaries, representing a range of spatial locations around the English coast and pressure risk categories, for analysis of a range of PFAS (to include PFOS and PFOA). This scoping study will provide evidence so that the need for any longer term monitoring requirements can be evaluated.
General aim: To obtain initial PFAS concentration data for estuarine sediments from a range of English estuaries.

Objective 1. (EA): To obtain sediment samples from the identified estuaries, via agreed methodologies, and deliver the samples to CEFAS immediately following the surveys. Provision of survey report identifying locations.

Objective 2. (CEFAS): Analysis of PFAS concentrations in the collected sediment samples. Range of PFAS chemicals to be analysed as per CEFAS analytical suite - PFBuA, PFPeA, PFHxA, PFHpA, PFOA, PFNA, PFDcA, PFUnA, PFDoDA, PFTrDA, PFTeDA, PFBuS, PFPeS, PFHxS, PFHpS, PFOS, PFNS, PFDcS, PFBuSA, PFHxSA, PFOSA, 4:2FTS, 6:2FTS, 8:2FTS, PFECHS, NaDONA, HPFO-DA, 9Cl-PF3ONS, 11Cl-PF3OUdS, NMeFOSAA and NEtFOSAA). Provision of concentration data in spreadsheet format.

Objective 3. (EA/CEFAS): Consider future PFAS evidence needs, including monitoring data, based on the data outputs of this initial screening project.

Defra, 2021. Determining levels of PFAS chemicals in estuarine and coastal sediments. Cefas report C8115 for Defra project ME5234. 53pp.
Project Documents
• TRP - Technical Report : ME5234 2021 PFAS chemicals in estuarine and coastal sediments final report   (1726k)
Time-Scale and Cost
From: 2020

To: 2021

Cost: £35,813
Contractor / Funded Organisations
C E F A S (CEFAS), Environment Agency
Marine Sediments