容百川
第1楼2012/04/02
PM2.5 is just one of the threats to human body, but not the dangerest one. The most dangerous pollutant is Dioxin/furans,which is called King of the toxic!Even dioxins are very toxic, it is very hard to detect them for their concentration is far lower than the limit of detection of the analyzers.
symmacros
第3楼2012/04/02
particulate matter (PM),
PM2.5: particles smaller than 2.5 micrometers.
please refer to: http://en.wikipedia.org/wiki/Particulates
rock_rock
第5楼2012/04/05
Yes, PM 2.5 is only part of the environmental problem. However, it is an important indicator of the overall environmental conditions of big cities. There are many much more harmful substances in atmosphere, but the concentraction is relatively much lower and with more limited sources.
Now the main concern is not about which pollutant is more critical. The direction is that if the country is unable to improve PM2.5, we going to pay for it at the expenses of public health which is in turn a huge public costs in medical system.