The following is an excerpt from our report: Exposing the Heavy Metal Concentration of PM2.5 in Beijing.
From December 3, 2012 to January 18, 2013, Beijing experienced the most severe episode of air pollution since PM2.5 monitoring data became available.
In this period, Greenpeace carried out monitoring of individual PM2.5 exposure to nine volunteers in the Beijing area using individual samplers (with a duration of 22 days and 42 samples), and also entrusted the Public Health Faculty of Peking University to monitor PM2.5 in the air (for 15 days) on the 6th floor platform of their building. A series of detection and analysis tests were carried out, as well as on the samples from individuals.
Analysis of heavy metal concentrations in the air show the concentration of arsenic in PM2.5 is above the norm. This alarming fact deserves greater attention from the Municipal Government of Beijing and Ministry of Environmental Protection of the People’s Republic of China.
- During the detection period, the average daily concentration median of heavy metal arsenic in Beijing's PM2.5 was 23.08 Ng /m3. According to Ambient Air Quality Standards issued in February 2012, the annual mean reference concentration limit value is 6 Ng /m3, meaning the concentration detected during the course of this research is 3.85 times the limit value. During heavy pollution days, the concentration median reached 34.68 Ng /m3, and the highest average daily concentration during this period reached 70.91 Ng /m3.
- During the 15 detection days, there were 12 days in which arsenic concentration rose above the annual mean reference limit value taken from Ambient Air Quality Standard, four days in which cadmium concentration rose above the annual limit value, and two days in which lead concentration rose above the limit value.
- During the 22 day detection period, the median individual arsenic exposure concentration of the nine volunteers was 12.13 Ng /m3. During heavy pollution days, the median of individual arsenic exposure average daily concentration was 24 Ng /m3. On December 19, the arsenic exposure average daily concentration median for one of the volunteers sat at 58.87 Ng /m3.
- Among the 42 person-times detection, the individual arsenic exposure concentration of 29 person-times is above the annual mean reference limit value.
- Compared to previous research, the arsenic concentration of PM2.5 in Beijing is constantly at a high level. And while the levels of this period are lower than previous, it is still significantly higher than other international cities.
Read the entire report: Exposing the Heavy Metal Concentration of PM2.5 in Beijing.