| Summary: | 碩士 === 台北醫學院 === 醫學研究所 === 85 === Lung cancer has become prevalent since early 1950s. The
standardized mortalities of lung cancer have been obviously
increased in Taiwan year by year, came up to 8 times level from
1954 to 1990 in Taiwan with sex ratio of male to female around
2.0 and with a rather obvious area -specific distribu-tion.
Some carcinogenic and mutagenic substances of air-suspended
particulates were probably the important pathogenic risk
factor of lung cancer,this may also be considered to being
related with urbanization and industrialization. However the
health hazard effects of air pollution are principally
detected out from respiratory diseases. There are more and
more evidences showed the close relationship between high air
pollution and lung cancer incidence. Owing to the
multiple causations of lung cancer, we first try to assess
rather directly the genotoxic responses of air suspended
particulate samples.The sampling areas of urban and rural
townships around the Formosa island were selected according to
the high,middle and low levels of standardized mortality rates
of female lung cancer in Taiwan from 1972 to 1983 for mostly
preclude the confounding effect of personally smoking.
A routine air sampling procedure by 24 hrs suction with the high
volume airsampler(Model GMWL-2000) was carried out once a time
at each selected township from Jan. to April, 1990. The glass
fiber filters were extracted by Hoffman's method. Then the
mutageni-cities of extracted tars were assayed by the Ames
Salmonella/Mammalian Microsome Mutagenicity Test using
Samonella typhimurium TA98 with S9 mix addition. We also
checked and correlated the corresponding pollution data with
the meteorological conditions on precipitation and win speed.
Meanwhile, those female lung cancer mortality rates of 1994-1995
were used as the probable outcome indices.
The average weights of particulate matters were increased with
the ascend-ing order of mortality levels of lung cancer, and the
mutagenicities come out rather proportional to the levels of
pollution when we calcu-lated the total mutagenicity by
mutation responses timing together with the sample particu-late
weight. There were found a good correlation between the total
mutageni-city and the levels of female lung cancer mortality (
p<0.025). We also found that these total mutagenicities were
rather area-specifically distributed ( p = 0.033).
Our cross-sectional analysis on the total mutagenicity indicates
that there is a significant relationship between the incidence
of lung cancer and thelevel of air pollution.We need a more
long-term follow-up study to confirm the exact causal
relationship between air pollution and lung cancer.
|
|---|
