Where+is+air+pollution+a+problem+08

matter, μg/m³ (2004) ||~ City || Air pollution is usually concentrated in densely populated metropolitan areas, especially in developing countries where environmental regulations are generally relatively lax. However, even populated areas in developed countries attain unhealthy levels of pollution.
 * ~ Most Polluted World Cities by PM[|[31]] ||
 * ~ [|Particulate]
 * 169 || [|Cairo, Egypt] ||
 * 150 || [|Delhi, India] ||
 * 128 || [|Kolkata, India] (Calcutta) ||
 * 125 || [|Tianjin, China] ||
 * 123 || [|Chongqing, China] ||
 * 109 || [|Kanpur, India] ||
 * 109 || [|Lucknow, India] ||
 * 104 || [|Jakarta, Indonesia] ||
 * 101 || [|Shenyang, China] ||