On the basis of my independent study, I concur with Cui, et al, in their article, "Air Pollution and Case Fatality of SARS in the People's Republic of China: An Ecologic Study". Cui, et al wrote in conclusion, "that air pollution was associated with increased risk of dying from SARS."
However, their explanation of "API" is deficient. They wrote, "Air pollution was evaluated by air pollution index (API) derived from the concentrations of particulate matter, sulfur dioxide, nitrogen dioxide, carbon monoxide and ground-level ozone."
This is problematic. China's API is derived only from the single pollutant with the highest reading, as stated here:
www.epd-asg.gov.hk/api_you/eng/api_youf.html
"APIs for each of these five pollutants are calculated and the highest API number is reported as the API of that hour."
The reader, or writer, who assumes that API is a mean or composite, or behaves as if it were such, would misinterpret or misrepresent the actual, effective air pollution levels.
If I may be permitted to reference my overview of the SARS problem, it is, "The SARS Epidemic: Are Viruses Taking The Rap For Industrial Air Pollution?", published online by the Weston A. Price Foundation.
Environmental Health
Explanation of API is not sufficient
13 March 2004
On the basis of my independent study, I concur with Cui, et al, in their article, "Air Pollution and Case Fatality of SARS in the People's Republic of China: An Ecologic Study". Cui, et al wrote in conclusion, "that air pollution was associated with increased risk of dying from SARS."
However, their explanation of "API" is deficient. They wrote, "Air pollution was evaluated by air pollution index (API) derived from the concentrations of particulate matter, sulfur dioxide, nitrogen dioxide, carbon monoxide and ground-level ozone."
This is problematic. China's API is derived only from the single pollutant with the highest reading, as stated here:
www.epd-asg.gov.hk/api_you/eng/api_youf.html
"APIs for each of these five pollutants are calculated and the highest API number is reported as the API of that hour."
The reader, or writer, who assumes that API is a mean or composite, or behaves as if it were such, would misinterpret or misrepresent the actual, effective air pollution levels.
If I may be permitted to reference my overview of the SARS problem, it is, "The SARS Epidemic: Are Viruses Taking The Rap For Industrial Air Pollution?", published online by the Weston A. Price Foundation.
Jim West
Chairman
Science Committee
NoSpray Coalition
New York City
Competing interests
None