Hanoi, Vietnam, recently experienced critically hazardous air pollution levels, topping global charts multiple times this winter. The city's rapid economic growth has resulted in severe air quality, with January's average Air Quality Index exceeding 300, prompting health warnings. The pollution, described as a stinging, chemical-smelling fog, obscures the city's skyline and highlights the environmental consequences of Vietnam's development.

Prepared by Olivia Bennett and reviewed by editorial team.