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A chemical elements
balance (CEB) method and a factor analysis (FA)
method were used to estimate the contribution of
particle sources to ambient suspended particulate
matters (SPM).
The SPM samples were
collected simultaneously at four sites around Nagoya
city in November and December 1990. Elements and
ions were analyzed using an organic element analyzer,
ICP-AES, AAS and ion chromatography.
The contributions of six major sources (soil, sea
salt, heavy oil combustion, iron and steel industry,
refuse incinerator and diesel engine) and secondary
particulate were calculated by the CEB method using
seven elements of elemental carbon, Na, Al, K, V,
Fe and Zn. Nearly 75% of the SPM can be a accounted
for by primary and secondary aerosols. On the other
hand, those of diesel engine, secondary particulate
and soil were considerably large. The contribution
of iron and steel industry, heavy oil combustion
and refuse incineration were less than 5%.
On factor analysis
of the data of 16 samples for 15 chemical components,
four factors were identified. These factors were
associated with not only source types but also weather
conditions and regional feature. Therefore it is
necessary to take this fact into consideration in
estimating source contributions from the absolute
factor score. However, FA method is very useful
in determining the source apportionment of the SPM
in the area with no source profile data. Since precision
of the source contributions calculated using the
CEB method depends on the reliability of the data
of source emission composition it is extremely important
to accumulate that source data.
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