PSE estimates the health risks of a massive methane super-emitter event that happened during London Climate Action Week

In June, researchers from PSE Healthy Energy were at London Climate Action Week, meeting with policymakers, community groups, and fellow scientists to discuss the air quality impacts and human health risks of air pollutants that travel with methane. Our recent findings show that European distribution-system gas carries benzene, a known human carcinogen, at concentrations 9 to 73 times higher than what we’ve measured in North America, and that when a methane super-emitter occurred in Cheltenham, modeled benzene concentrations near the leak may have been four times the European Union’s 8-hour occupational exposure limit. While we were there, Carbon Mapper detected a massive methane super-emitter event near Falkirk, Scotland. This is exactly the kind of event our Methane Risk Map (MRM) is built to make sense of, translating methane emissions events into air quality and human health risk maps, showing what methane super-emitters mean for the health of people living near them. So, we stepped in to begin analyzing what hazardous air pollutant concentrations people living nearby could have been exposed to. 

As reported by Data Desk, Carbon Mapper’s Tanager-1 Satellite captured the methane super-emitter on June 23 above the Avonbridge Compressor Station operated by National Gas. Approximately 200,000 cubic meters of natural gas, roughly 130 metric tons of methane, was vented as pre-planned maintenance activity–enough to heat about 200 UK homes for a year. Using gas composition data we recently collected in Europe, alongside our rapid air quality modeling and risk-mapping pipeline developed for the MRM, and conservative early estimates, PSE estimated that benzene levels exceeded health risk benchmarks across an area of 2.4 km^2 and up to four kilometers from the super-emitter source. Despite the release lasting less than one day, we estimated that about 140 residential buildings, representing approximately 500 people, were within the health risk area in the nearby town of Avonbridge. 

This event in Scotland represents just one example, but it demonstrates something worth noting: the health risks posed by methane emissions events that we’ve found across the U.S. through the MRM are not unique to the U.S. Our research consistently finds that when oil and gas infrastructure emits methane–from the wellhead to the end of the pipeline– air quality is impacted and people can be exposed to health risks from toxic pollution as well. Yet, these methane super-emitter events are primarily viewed as a climate issue, rather than a source of place-based human health risk. By translating methane super-emitter event data from satellites into estimates of local air quality impacts and associated human health risks, policymakers, regulators, and other stakeholders can use this information to make better-informed decisions about monitoring, mitigation, enforcement, and human health protection, as we’ve shown in the U.S.

This animation shows how benzene concentrations could have evolved around the Avonbridge Compressor Station at Falkirk, Scotland, on June 23, 2026. We modeled the emissions event over a 24-hour time window, with each frame representing a one-hour average. Cooler colors represent lower concentrations, and warmer colors represent higher concentrations. The dashed purple line marks the health risk area. The health risk area evolves with wind speed and direction throughout the day, indicating that nearby communities could have been within the risk area depending on how the emissions rate evolved over time, the event’s exact duration, and local weather conditions.