Funder: California Endowment, San Diego Foundation
Partners: San Diego Prevention Research Center, San Diego State University School of Public Health

The Healthy Borders Study was a series of research studies that investigated the impact of border crossing experiences and delays on San Ysidro residents and daily border-crossing commuters. This study culminated in a two-day binational conference that brought together environmental health academics and practitioners, as well as community members to develop a white paper on proposed next steps to reduce traffic-related air pollution in the San Ysidro-Tijuana border region. 

Key Findings:

• Community had multiple concerns over long border delays, health effects from vehicle emissions

• At the Port Of Entry (POE) location where pedestrians cross, Ultrafine Particulate Matter concentrations were 3-4 times higher than in San Ysidro and up to 10 times higher than in Imperial Beach

• Black carbon levels were influenced by wind patterns, indicating regional pollution sources. 

The study’s results were shared with the U.S. federal government, informing the ongoing San Ysidro Land Port of Entry Project. Casa Familiar has advocated for community-driven design improvements, and in May 2012, a binational conference at Casa Familiar’s Civic Center brought together experts and residents to propose solutions for reducing traffic-related air pollution in the San Ysidro-Tijuana border region.

View Reading Materials Here 

Funder: California Air Resource Board (CARB)
Partners: University of Washington, San Diego State University School of Public Health

This project focused on addressing air quality concerns near the US-Mexico border by the continuation of low-cost sensors to monitor pollution and provide actionable insights for mitigating community exposure. 

Key Findings:

• Higher pollution levels were detected near roads and border areas. 

• October to March and overnight hours consistently showed the worst air quality, while morning traffic caused spikes in near-road pollution, suggesting suggest higher exposure risks for children during morning outdoor activities 

• Impact of COVID-19: While passenger vehicle traffic decreased during restrictions, black carbon levels unexpectedly rose, likely due to continued commercial truck activity and increased waste burning.

These findings highlight the need for targeted interventions, such as reducing vehicle emissions, adopting green infrastructure, and fostering cross-border collaborations to improve air quality in affected communities.

Funder: North American Development Bank - Border 2020 Program
Partners: University of Washington, San Diego State University, Universidad Autónoma de Baja California

This project explored the impact of emissions on air quality in Tijuana communities adjacent to the San Ysidro and Otay Mesa Ports-of-Entry (POEs), the busiest border crossings in the region. Using low-cost air quality monitoring technologies, the study gathered valuable data to understand pollutant levels and their implications for public health.

Key Findings:

• PM2.5 concentrations at POEs were significantly elevated compared to other sites in the region.

  • 50% higher at Otay Mesa and 5% higher at San Ysidro.

• Pollutant levels showed clear links to traffic flow, with diurnal variations highlighting vehicle emissions.

• Emphasized the need for regulatory systems to track long-term pollution trends, on both sides of the border.

This study underscores the importance of expanded monitoring systems at key border crossings to improve air quality and public health outcomes

View Full Report Here 

Funder: California Air Resource Board (CARB)
Partners: San Diego State University, University of Washington

This project's goal is to keep collecting data in the border region, by renewing the low-cost air quality monitors deployed in the previous studies. This project also has a new pilot component of mobile monitoring. This monitoring will allow to explore new ways of monitoring with less equipment.

(Key findings & full report coming soon)