Earth System Science Data
2026
Shared — curated by The Gufo editorial team
POPE: an annual global half degree emission inventory for PFAS 1950–2020
Pascal Simon*, Martin Otto Paul Ramacher, Stefan Hagemann, Volker Matthias, Hanna Joerss, Johannes Bieser
Helmholtz-Zentrum Hereon (Geesthacht, Germany)
Received: 2026-10-31 · Published: 2026-08-03
© 2026 The Author(s) and the original publisher.
Abstract
Abstract. This study presents a global multi compartment Persistent Organic Pollutant Emissions model and inventory: POPE. The model computes temporally and spatially resolved model ready emissions for 23 of the most widely used Per- and Polyfluoroalkyl Substances (PFAS) distinguishing between emissions to air and emissions to water covering the time span from the first industrial scale production in 1950 up until 2020 on an annual basis on a grid with 0.5° resolution. The POPE model distributes estimated total PFAS emissions in space and time based on several data sets such as the E-PRTR, NACE and US-EPA FRS in combination with socio-economic data as population and GDP complemented by estimates for individual point sources, such as industrial sites and airports, whereby the source activity is dependent on regional changes in production volumes, usage quotas, and recapturing efficiency over time. It includes emissions by industrial production, diffuse emissions through usage and disposal of consumer products, secondary emissions from the reaction of precursors, and emissions by firefighting exercises on airports using Aqueous Film Forming Foams. It is demonstrated that the POPE emission inventory is compatible with current global emission estimates, and temporal and spatial variability of the emissions is explored. A comparison of independent measurements with modelled river concentrations based on the POPE emission inventory is provided. The POPE emission inventory is meant to be used as input for atmospheric and marine chemistry transport models, eventually allowing to assess the environmental fate of PFAS. POPE can be used to create hypothetical future emission scenarios, enabling model based predictions which can inform policy decisions. This is important given that even with a theoretical global fade-out of PFAS production, significant legacy pollution is still to be expected.
Summary
PFAS ('forever chemicals') are a large group of synthetic substances used widely in industry and consumer products because of their resistance to heat, water and oil. Because they barely break down in the environment, understanding where and when they have been released is important for predicting their future spread and impacts. This paper introduces POPE, a global model and inventory that estimates emissions of 23 widely used PFAS to air and water from 1950 to 2020, mapped at a fine spatial resolution (0.5°) and on an annual basis.
POPE combines several types of data, including industrial emission registers, economic activity classifications, population and GDP figures, and specific point sources such as factories and airports, to distribute total PFAS emissions across space and time. It accounts for different emission pathways: direct industrial production, diffuse release from consumer product use and disposal, secondary formation from precursor chemicals, and releases from firefighting foam use at airports. The authors show that POPE's estimates are consistent with existing global emission figures and compare modelled river concentrations with independent measurements. The inventory is designed to serve as input for atmospheric and marine models that simulate PFAS environmental fate, and can also be used to construct future emission scenarios to support policy-making, given that legacy PFAS pollution will persist even if production stops.
Plain-language summary by The Gufo; the paper is the authors’ own text.
Key findings
- POPE provides a spatially (0.5° grid) and temporally (annual, 1950–2020) resolved global emission inventory for 23 major PFAS compounds, separated into emissions to air and to water.
- The inventory integrates industrial production, diffuse consumer product emissions, secondary emissions from precursor degradation, and emissions from firefighting foam use at airports.
- POPE's emission estimates are shown to be compatible with current global PFAS emission estimates.
- Modelled river concentrations derived from the POPE inventory were compared against independent measurements, and the inventory is intended for use in atmospheric and marine chemistry transport models as well as for constructing future emission scenarios.
