New research to help Monterrey cut toxic black carbon pollution by identifying high-impact health and climate solutions

By Veronica Southerland and Amisha Kumar

What’s new: EDF is thrilled to join a new four-year research project in Monterrey, the capital city of Nuevo Leon, Mexico, to evaluate which clean air interventions are the most lifesaving to reduce exposure to the super pollutant, black carbon. Funded by the Wellcome Trust and led in collaboration with the Instituto Nacional de Salud Pública (INSP) — Mexico’s equivalent of the National Institutes of Health — the project will assess how the city’s existing clean air strategies can deliver real reductions in black carbon and translate those findings into policy guidance for decision-makers.

Why it matters: Air pollution kills more people each year than traffic accidents in Mexico. In Monterrey, the country’s second-largest metropolitan area, years of industrial growth have left residents breathing some of the highest concentrations of particulate matter in the country. Black carbon — a component of soot and a form of fine particulate matter, PM2.5 — penetrates deep enough into the lungs to bypass the body’s natural filtering systems, entering the bloodstream directly. Once there, it reduces the ability to take in oxygen, triggers inflammatory responses and affects the entire cardiovascular system. Globally, PM2.5 deaths exceed those from AIDS, HIV, tuberculosis and several other diseases combined.

Tackling black carbon is also one of the most efficient paths to slowing climate change. Unlike CO2, which persists in the atmosphere for centuries, black carbon is a short-lived climate pollutant, meaning reductions deliver results within years, not generations. For communities trying to avoid climate tipping points while protecting public health, it represents an opportunity to address both crises at once.

Inside the project

The project has three main components. The first is epidemiological, focused on curbing negative cardiovascular outcomes. The second looks at stakeholder engagement and policy development and is handled by local partners at INSP. The third aspect, conducting the health impact assessment, is led by EDF.

The vision for the project is to determine which clean air interventions will deliver the most value from limited resources.

The health impact assessment involves modelling changes in emissions attributed to climate interventions in the city, which are then fed into InMAP — a recently developed model that estimates the human health impacts caused by air pollutant emissions — to gauge how those changes affect air quality and, ultimately, human health. As emissions mix with the atmosphere and disperse, InMAP produces concentration changes that can be used to estimate the scope of the health benefits gained from each intervention.

The analysis will also examine where, geographically, the burden of black carbon pollution falls, tracking not just where emissions originate, but where atmospheric conditions carry them, which can shift health impacts onto communities far from the source.

What this could mean for health in Nuevo Leon and beyond

By putting a number on the health benefits of specific interventions — estimating avoided hospitalizations and associated cost savings — the project aims to give government officials a clearer basis for prioritizing actions on health grounds, not climate impact alone.

A key goal is also replicability. The research team chose to use InMAP in part because it is computationally lighter than traditional atmospheric modelling, making it more accessible to cities and countries with limited technical resources. The methods developed here are designed to be adapted elsewhere.

The project is fundamentally community-driven, part of a larger effort where results will be shared with the state government to inform decisionmaking.

The project builds on modelling work that EDF previously conducted in Mexico on methane and PM2.5 and sits within a broader cohort of Wellcome Trust-funded studies on climate action in low- and middle-income countries running over the next four years.

What’s next: The project will begin in July 2026 and is set to run four years, focusing on the research for the first two. The partners plan to eventually translate the results into policy briefs and peer-reviewed science to support decision-makers in Nuevo León and beyond. By the end of the four years, the partners aim to demonstrate methods that can be applied globally to estimate the health co-benefits of climate action.