5 Most Oxygen Friendly Cities in the US

3. Castroville

Annual Average PM2.5 Concentration In 2022 (μg/m³): 0.8

Castroville is located in Texas and is one of the most oxygen-friendly cities in the US. The city is renowned for its beautiful residential area and architecture. According to the IQAir index, in 2022, Castroville had an annual average PM2.5 concentration of 0.8μg/m³.