How polluted are 8 of the most visited cities in the world?
Cairo dominates the ranking
A new study has revealed the pollution levels of eight of the world’s top tourist cities, shedding light on the environmental challenges faced by popular destinations. The research assessed various city pollution factors based on their average annual visitors.
The study’s methodology involved analysing cities based on annual visitor numbers, with data gathered from platforms such as Statista. The pollution levels were assessed through key indicators, including AQI, PM2.5 levels, noise pollution, and water quality. These factors were weighted and combined to produce a final pollution score, comprehensively assessing the environmental conditions in these global tourist destinations.
DIPNDIVE’s study analysed these metrics and developed a comprehensive pollution score to rank cities according to their environmental conditions.
1 Cairo
Cairo, Egypt, is the most polluted tourist city, with an average of 14.9 million annual visitors. The city recorded an AQI of 160, indicating inferior air quality, and PM2.5 levels reached 68.4 µg/m³, far exceeding the World Health Organization’s recommended safe limit of 5 µg/m³. In addition to its severe air pollution, Cairo’s noise levels were reported at 85 dBA, and the water quality index stood at just 45, contributing to its high pollution score of 98.
2 Los Angeles
Following Cairo, Los Angeles, USA, is the second most polluted city, with 49.1 million visitors annually. Despite its popularity, Los Angeles grapples with significant air quality issues. The city recorded an AQI of 116 and PM2.5 concentrations of 41.5 µg/m³, placing it well above the safe limit. Other contributing factors include noise pollution at 50 dBA and a water quality index 68, resulting in a pollution score of 51.17.
3 Hong Kong
Hong Kong, with 14.7 million annual visitors, is third on the list. The city’s AQI of 83 indicates unhealthy air quality, while PM2.5 levels were measured at 26.5 µg/m³, five times the WHO’s safe limit. Noise levels in Hong Kong averaged 91.4 dBA, and the water quality index was reported at 69, giving the city a pollution score of 50.33.
4 Bangkok
Bangkok, Thailand, ranks fourth with 12.2 million visitors per year. The city faces significant pollution challenges, including an AQI of 91 and PM2.5 concentrations of 30.8 µg/m³, more than six times above the recommended safe level. Noise pollution in Bangkok averages 55.3 dBA, and the water quality index stands at 56, producing a pollution score of 48.97.
5 San Diego
San Diego, USA, is the fifth most polluted city, attracting 31.8 million visitors annually. With an AQI of 73 and PM2.5 levels reaching 20.8 µg/m³, delicate particulate matter significantly impacts San Diego’s air quality. Noise pollution at 75 dBA and water quality issues further exacerbate the environmental concerns, resulting in a pollution score 40.04.
6 Phuket
Phuket, Thailand, ranks sixth, with 8.4 million visitors annually. The city recorded an AQI 58 and PM2.5 concentrations of 13.1 µg/m³. Noise levels averaged 71 dBA, and water quality was rated at 54, leading to a pollution score 40. Despite its scenic appeal, Phuket faces significant environmental challenges.
7 Athens
Athens, Greece, attracts 6.4 million visitors yearly and ranks seventh for pollution. The city’s AQI of 81 and PM2.5 levels of 25.1 µg/m³ are significantly above safe limits. Noise pollution at 55 dBA and a water quality index 63 add to the environmental concerns, resulting in a pollution score of 39.87.
8 Cancun
Cancun, Mexico, is the eighth-most polluted city, with 10.8 million visitors annually. Its noise pollution levels are the highest among the cities studied, averaging 103 dBA. While the city’s AQI of 15 reflects relatively good air quality, the noise and water quality indices (55) contribute to its pollution score 36.66.
A DIPNDIVE spokesperson stated: “While travel remains one of life’s greatest pleasures, it is crucial to recognise the environmental impact that tourism has on the destinations we love. Cities like Los Angeles and Bangkok face immense challenges in managing air quality and noise levels. Despite their allure, places like Cancun highlight how even idyllic locations can struggle with unique pollution issues.”
Hero image: Cairo recorded an AQI of 160, indicating inferior air quality, and PM2.5 levels reached 68.4 µg/m³, far exceeding the WHO’s recommended safe limit of 5 µg/m³. Credit: David McEachan
