Map reveals world’s most polluted tourist hotspots

A recent analysis has highlighted the world’s most polluted tourist destinations, revealing concerning environmental conditions in some of the most visited cities.

The study, conducted by DIPNDIVE, evaluated cities based on their pollution levels, factoring in air quality, water quality, noise levels and PM2.5 concentrations—tiny, harmful air particles. These data points were combined into an overall pollution score to rank cities by environmental challenges.

Egypt’s Cairo, which attracts 14.9 million visitors annually, emerged as the most polluted tourist city, with alarming environmental indicators. Its Air Quality Index (AQI) stood at a staggering 160, signifying unhealthy air conditions, while PM2.5 levels reached 68.4 µg/m³—over 13 times the World Health Organization’s (WHO) recommended safe limit of 5 µg/m³.

Los Angeles, with 49.1 million annual visitors, ranked as the second most polluted tourist city. Its AQI of 116 and PM2.5 levels of 41.5 µg/m³ underscore serious air quality problems. The sprawling urban landscape struggles with emissions and congestion that exacerbate environmental problems in this global tourist hub.

Hong Kong, which welcomes 14.7 million visitors annually, placed third. Its AQI of 83 and PM2.5 levels of 26.5 µg/m³ indicate significant air pollution. Additionally, its water quality index of 69 highlights challenges in maintaining clean water resources, compounding the city’s environmental pressures.

Bangkok, a favorite among tourists that draws 12.2 million visitors annually, ranked fourth, with an AQI of 91 and PM2.5 concentrations of 30.8 µg/m³—over six times the WHO’s safe limit. Noise and water pollution further affect the Thai city’s environmental conditions.

San Diego is the fifth-ranked city, with 31.8 million annual visitors. It had an AQI of 73 and PM2.5 levels of 20.8 µg/m³. Noise and water pollution also contributed to its overall pollution score of 40.04, revealing challenges often overlooked in this coastal city.

“Travel is one of the most enriching experiences, but it’s important to recognize how environmental factors can impact our journeys and the destinations we visit,” a DIPNDIVE spokesperson said in a statement.

“Cities like Los Angeles and Bangkok demonstrate the challenges of managing air quality and noise in highly urbanized tourist hubs. On the other hand, destinations like Cancun remind us that even seemingly pristine locations can face unique environmental concerns, such as high noise pollution,” the statement added.

The study used data from platforms like Statista and SoundPrint, assessing pollution levels through weighted metrics, including AQI, PM2.5 concentrations and noise and water quality indexes.

Each factor was scaled between 0 and 100 and weighted depending on the relative importance determined by DIPNDIVE. The scores were then combined into an overall pollution ranking out of 100.

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