Emerging environmental health issues in low- and middle-income countries

Emerging epidemiological evidence has demonstrated that ambient air pollution,such as particulate matter(PM),is associated with in-creased cardio-respiratory mortality and morbidity.1-2 Air pollution has been recognized as the single biggest environmental risk factor for at-tributable burden of noncommunicable diseases(NCDs),3 which has provided strong rationale for actions reducing population exposure to air pollutants in particular countries or regions even on a global scale.