Exposure to ambient fine air particulate matter (PM2.5) pollution may pose an adverse health hazard risk to infants and children. The under-5 mortality rate serves as an estimate of probability that a child might die between birth and age of five following exposure. This rate has been used by the United Nations as a prime indicator of exposure when setting and evaluating sustainable development goals (SDGs). These particular SDGs targets were set to avoid preventable deaths in this age group. Few investigators examined the relationship between post-birth exposure to PM2.5 and under-5 mortality. To examine this association, the mean annual PM2.5 levels of 65 municipal districts were measured in Taiwan from 2013 to 2022 and then divided into tertiles. The under-5 mortality rates per 1000 live births included the following parameters PM2.5 levels, urbanization, physician density, and mean annual household income. Weighted-multiple linear regression was used to compute the adjusted risk ratios (RRs) and their 95% confidence intervals (CIs). Data demonstrated that children living in districts with the highest PM2.5 levels to be at significantly increased risk of mortality at under-5, with adjusted RR (95% CI) calculated at 1.12 (1.02-1,23) for those residing in municipalities with mean PM2.5 between 23.7 and 27.49 ug/m3 compared to those living in districts with the lowest PM2.5 levels. An increase a 0.7% in under-5 child mortality per each 1 ug/m3 rise in PM2.5, suggested long-term exposure to PM2.5 enhances the risk of mortality under-5 children in Taiwan.

Infants and children may be potentially susceptible to harm from ambient fine particulate matter (PM2.5) pollution because of the following characteristics (1) immature immune systems (2) not yet fully developed respiratory systems (3) possess a higher absorption rate of pollutants, and (4) and daily activities may expose infants to varying levels. However, few studies have examined the possible correlation between exposure to PM2.5 and mortality in infants. Therefore, the aim of this study was to investigate the association between long-term exposure to ambient PM2.5 and post-neonatal mortality in 65 municipal areas across Taiwan. The mean annual PM2.5 levels of each municipality were categorized from 2013 to 2022 and divided into tertiles. The natural logarithm of the annual post-neonatal mortality rates per 1000 live births was assessed with respect to PM2.5 level, urbanization level, physician density, and mean annual average household income. Weighted-multiple linear regression was utilized to compute the adjusted RRs and their 95% confidence intervals (CIs). When data were not stratified by PM2.5 levels, a significant positive association was observed between long-term lifetime exposure to ambient PM2.5 and post-neonatal mortality rates after adjustment for physician density, urbanization level, and average household income. When PM2.5 levels (in tertiles) were stratified, a positive but nonsignificant trend was found in post-neonatal mortality frequency from the lowest to the highest PM2.5 category. These findings suggest that long-term exposure to PM2.5 increases the risk of post-neonatal mortality rates in Taiwan.

Over the past 5 decades, sex ratio at birth (SRB) has declined significantly. It is noteworthy that SRBs may vary considerably across geographical regions and time periods, making them a valuable indicator of general population health and a potential signal of adverse environmental conditions. Long-term exposure to fine particulate matter (PM2.5) was associated with higher SRBs as well as increased lung cancer risk. It is unclear whether the relationship between these two parameters is coincidental or whether elevated SRBs in PM2.5 air-polluted areas might serve as a predictor of lung cancer risk. The aim of this study was to examine the possible association between SRBs and the likelihood of death attributed to lung cancer. In order to achieve this aim, studies were conducted, in which PM2.5 levels, number of SRBs, and standardized mortality ratio (SMR) for lung cancer were determined for 66 municipalities in Taiwan from 2010 to 2023. SRBs were found to display a non-significant positive association with lung cancer mortality risk in women. The relative risks (RRs) in the second, third, and fourth quartiles of SRB were 1.019 (95% CI = 0.961-1.080), 1.031 (95% CI = 0.973-1.093), and 1.028 (95% CI = 0.970-1.090), respectively, compared with the lowest quartile of SRB. For men, they were 0.992 (95% CI = 0.946-1.040), 0.996 (95% CI = 0.950-1.045), and 1.03 (95% CI = 0.982-1.081). Data suggested that routine monitoring of SRBs may not be sufficiently sensitive to serve as a reliable screening measure for detection of population-level health risk based upon lung cancer findings, particularly in areas with high levels of PM2.5 air pollution.

Infants' and children's health is particularly susceptible to exposure to various environmental contaminant insults as their immune systems are immature and daily activities may present differing patterns of exposure. Although some studies noted an association between long-term exposure to ambient fine particulate matter (PM2.5) and increased infant mortality frequency, few investigations examined the relationship between reduced exposure to PM2.5 and changes in infant mortality rates. Therefore, this study was conducted to determine whether diminished levels of PM2.5 in Taiwan improved post-neonatal infant health. Avoidable premature post-neonatal infant mortality was employed as an indicator of health impact. A mean value was calculated for annual PM2.5 levels across Taiwan for the years 2006, 2015, and 2023. Using these averages and following WHO methodology, differences in the number of post-neonatal infant deaths attributed to ambient PM2.5 exposure were determined. PM2.5 concentrations fell markedly throughout Taiwan over the 20-year study period. In conjunction with this decline, a lowered health burden was noted, which was represented as a fall in post-neonatal infant deaths (14.8% in 2006 to 10.3% in 2023). Reduction in annual levels of PM2.5 to 10 mu g/m(3) was associated with a decrease in the total burden of post-neonatal infant mortality occurrence, with a 5.58-9.31% decline in PM2.5-related deaths during that period. Evidence indicates that exposure to PM2.5 air pollution poses a significant burden to Taiwan children's health. Our findings indicate that the potential benefits to children's health need to be given importance when considering improving air quality policies.

Sex ratio at birth (SRB) is a simple, noninvasive way to monitor the reproductive health of a population. Sex ratio at birth tends to vary across regions and time periods and has been declining globally over the last 50 years possibly due to exposure to environmental toxins, including endocrine-disrupting chemicals (EDCs) and other pollutants. The findings of few studies that assessed the relationship between ambient air pollution and SRBs have been inconsistent. The aim of this study was to investigate the possible association between long-term exposure to ambient PM2.5 and number of SRBs across 66 municipalities in Taiwan. Our data on annual numbers of male and female births were obtained from Taiwan's Department of Household Registration, Ministry of Interior Affairs, while PM2.5 data were obtained from Taiwan's Environmental Protection Administration (TEPA). Mean PM2.5 levels and number of SRBs were calculated for each municipality from 2010 to 2023. The municipalities were categorized into PM2.5 tertiles (low, medium, and high levels) and the relationship assessed between these tertile levels and number of SRB using a linear logistic regression model. Compared to the lowest PM2.5 level, the adjusted ORs for the middle and the highest tertile of PM2.5 levels were 1.015 (1.006-1.024) and 1.018 (1.008-1.029), respectively, noting a significant trend linking increased number of SRBs with higher PM2.5 levels. This finding is inconsistent with the known fact that male fetuses are more susceptible to environmental threats compared to female fetuses.

Many epidemiologic studies have reported an association between high concentrations of fine particulate matter (PM2.5) and increased mortality rates. Concurrently an association between decreased concentration of these airborne PM(2.5 )pollutants and a decline in mortality frequency was noted in certain investigations globally; however, only a very few of these studies were conducted in Asia. Taiwan was found to exhibit a 30% decline in ambient PM2.5 levels over the last 20 years. The aim of this ecological investigation was to examine the contribution of annual reductions in ambient PM2.5 to changes in age-standardized natural-cause mortality rates (ASRs) in 65 townships in Taiwan from 2006 to 2020 controlling for lung cancer mortality rate, physician density, and annual household income. Data demonstrated a 0.9/105 fall in adjusted ASR for every 10 ug/m(3) reduction in mean annual PM2.5 level in Taiwan during this 14-year period, suggesting a significant association between reductions in ambient PM2.5 levels and decreases in natural-cause mortality rates.

Sex ratio at birth (SRB) is a simple, noninvasive way to monitor the reproductive health of a population. Apparently only a few studies have assessed the relationship between ambient air pollution and SRBs. The studies that investigated this relationship have yielded inconsistent results. Ambient air pollution levels, including particulate matter (PM2.5) levels, have decreased in Taipei city after a mass rapid transit (MRT) system commenced operations in 1996. The aim of this study was to determine whether the changes in levels of PM2.5 after the implementation of the MRT system in Taipei may have influenced the concurrent alterations noted in the SRB. In order to assess this potential association, annual numbers of male and female births were obtained from Taiwan's Department of Household Registration, Ministry of Interior Affairs from 1992 to 2023. Mean yearly SRBs were calculated for 4 time periods, 1992-1995, 1996-2004, 2005-2015, and 2016-2023. Linear logistic regression was employed to evaluate the variation in officially reported PM2.5 levels during those periods and alterations in the ratios. The ratios for time periods 1 to 4 were 52.61%, 52.22%, 51.78%, and 51.67%, respectively. Compared to Period 1 (pre-MRT), the odds ratios for Periods 2, 3, and 4 were 0.98 (0.97-0.99), 0.97 (0.96-0.98), and 0.96 (0.95-0.98), respectively. The trend toward the decreased SRB was found to be gradual but significant.

The relationship between breast cancer mortality and air pollution was examined using an ecological design. The study areas consisted of 61 municipalities in Taiwan. Air quality data for recorded concentrations of fine particulate matter (PM2.5) from study municipalities for 2006–2009 were obtained as a marker of traffic emissions and were used as a proxy for polycyclic aromatic hydrocarbons (PAHs) exposure. Age-standardized mortality rates for breast cancer mortality were calculated for the study municipalities for the years 1999–2008. A weighted multiple regression model was used to calculate the adjusted risk ratio in relation to PM2.5 levels. Results showed that individuals who resided in municipalities with the highest PM2.5 were at an increased risk of death from breast cancer. This study is the first to suggest that exposure to high levels of PM2.5, a proxy measure of PAHs, may be associated with an increased risk of death from breast cancer. The findings of this study warrant further investigation into the role of air pollutants in the risk of breast cancer.

ABSTRACT According to the International Agency for Research on Cancer (IARC), airborne fine particulate matter (PM2.5), which is categorized as a Group I carcinogen, was found to lead to predominantly lung as well as other cancer types in humans. Hepatocellular carcinoma (HCC) is endemic in Taiwan where it is the second and fourth foremost cause of cancer deaths in men and women, respectively. Taiwan’s mortality rates for liver cancer vary considerably from one region to another, suggesting that the environment may exert some influence on deaths attributed to liver cancer. The aim of this investigation was to perform an ecologic study to examine the possible link between ambient PM2.5 levels and risk of liver cancer in 66 in Taiwan municipalities. To undertake this investigation, annual PM2.5 levels and age-standardized liver cancer mortality rates were calculated for male and female residents of these areas from 2010 to 2019. Data were tested using weighted-multiple regression analyses to compute adjusted risk ratio (RR) controlling for urbanization level and physician density. Annual PM2.5 levels of each municipality were divided into tertiles. The adjusted RRs for males residing in those areas with intermediate tertile levels (21.85 to 28.21 ug/m3) and the highest tertiles levels (28.22–31.23 ug/m3) of PM2.5 were 1.29 (95% CI = 1.25–1.46) and 1.41 (95% CI = 1.36–1.46), respectively. Women in these locations shared a similar risk, 1.32 (1.25–1.4) and 1.41 (1.34–1.49), respectively. Evidence indicated that PM2.5 increased risk of mortality rates attributed to liver cancer in both men and women in Taiwan.

While numerous studies have found a relationship between long-term exposure to airborne fine particulate matter (PM2.5) and higher risk of death, few investigations examined the contribution that a reduction of exposure to ambient PM2.5 levels might exert on mortality rates. This study aimed to collect data on changes in annual average ambient levels of PM2.5 from 2006 to 2020 and consequent health impact in public health in 65 municipalities in Taiwan. Avoidable premature mortality was used here as an indicator of adverse health impact or health benefits. Annual PM2.5 levels were averaged for the years 2006, 2010, and 2020. In accordance with World Health Organization (WHO) methodology, differences were estimated in the number of deaths attributed to ambient PM2.5 exposure which were derived from concentration-response data from prior epidemiological studies. PM2.5 concentrations were found to have been decreased markedly throughout Taiwan over the two-decade study. As the PM2.5 concentrations fell, so was the health burden as evidenced by number of deaths concomitantly reduced from 22.4% in 2006 to 8.47% in 2020. Data demonstrated that reducing annual mean levels of PM2.5 to PM10 ug/m3 was associated with decrease in the total burden of mortality, with a 2.22-13.18% fall in estimated number of PM2.5-related deaths between 2006 and 2020. Based upon these results, these declines in ambient PM2.5 levels were correlated with significant improvement in public health (health benefits) and diminished number of deaths in Taiwan.

ABSTRACT According to the US Environmental Protection Agency’s Integrated Science Assessment (ISA), there is a causal relationship between fine particulate matter (PM2.5) exposure and increased mortality rates. A similar association was also reported by the International Agency for Research on Cancer (IARC). While many studies are available on this relationship between PM exposure and elevated mortality frequency in Europe and North America, there are limited investigations in Asia. Thus, the aim of this study was to perform an ecological investigation to determine the relationship between exposure to ambient PM2.5 levels and all-cause mortality in 66 in Taiwan municipalities. To undertake this investigation, annual PM2.5 levels and age-standardized all-cause mortality rates were calculated for male and female residents of these areas from 2010 to 2020. Weighted-multiple regression analyses were used to obtain adjusted risk ratio (RR) controlling for possible confounding by urbanization level, physician density, and annual mean household income. Annual PM2.5 levels of each municipality were divided into tertiles. Data demonstrated that men residing in areas with intermediate tertile PM2.5 levels (21.06 to 27.29 µg/m3) and the highest tertiles levels (27.30–33.11 µg/m3) exhibited adjusted RRs of 1.06 (95% CI = 1.03–1.08) and 1.13 (95% CI = 1.10–1.16), respectively. Women in these locations displayed a similar risk, 1.03 (0.99–1.06) and 1.07 (1.04–1.11), respectively. These findings indicate that ambient exposure to PM2.5 increased risk for all-cause mortality rates in both men and women in Taiwan during this time period.

Airborne fine particulate matter (PM2.5) has been classified as a Group I carcinogen leading to lung cancer in humans by the International Agency for Research on Cancer (IARC). In Taiwan, where there is a growing incidence of this disease, lung cancer is currently the leading cause of cancer-associated deaths in women and second leading cause of deaths in men. Because tobacco use is rare in Taiwan, especially amongst women, the high incidence of this type of cancer was suggested to be attributed to the other external contaminants, including airborne PM2 pollution. In this ecologic study, a possible association between ambient air PM2.5 exposure and likelihood of death attributed to lung cancer was examined in Taiwan in 66 municipalities. Annual PM2.5 levels and age-standardized lung cancer mortality rates for male and female residents were calculated for years 2010 to 2019. Weighted-multiple regression was applied to analyze our data, adjusting for level of urbanization and physician density. For males, the adjusted risk ratios (RRs) for lung cancer mortality were 1.01 for municipalities with PM2.5 levels 21.85-28.21 ug/m3 and 1.07 for municipalities with 28.22-31.23 ug/m3, compared to those with the lowest PM2.5 levels. For females, these adjusted RRs were 0.99 and 1.06, respectively. Data demonstrated an association between chronic exposure to high levels of PM2.5 and increased likelihood of death attributed to lung cancer for both men and women in Taiwan. Further studies are needed to explore the relationship between PM2.5 air pollution exposure and risk of lung cancer histologic subtype.

A number of studies investigating the possibility that air pollutant exposures increases the risk of adverse effects on mental health including frequency of suicide and depression, is a major growing public health concern. Human data demonstrated that exposure to various ambient air contaminants including ozone (O3) adversely affected nervous system functions. It is also well-established that substance abuse produces central nervous system dysfunctions with resultant increase in suicide rates. However, the role of substance abuse in combination with O3 exposure on mental health remained to be determined. The aim of this investigation was to conduct a time-stratified case-crossover study to examine the possible correlation between short-term ambient O3 exposure and daily hospital admissions for substance abuse, including alcohol dependence syndrome and non-dependent abuse of drugs, in Taipei from 2009 to 2013. In our single pollutant model, a 35% rise in interquartile (IQR) O3 levels on cool days and a 12% elevation on warm days was associated with increase in mental health hospitalizations. In our two-pollutant models, O3 remained significantly associated with elevated number of hospitalizations after adding any one of possible air pollutants, PM10, PM2.5, SO2, NO2, and CO, to our model on cool and warm days. Data suggested that temperature may affect the association between outdoor ambient air O3 exposure and enhanced risk of hospitalization for substance abuse. Further study is needed to better understand these findings.

Fine particulate matter, particles less than 2.5 um in diameter (PM2.5), is an important environmental human health factor to consider. The long- and short-term influence of PM2.5 on health has been extensively studied in relation to many health outcomes, although few investigations examined the consequences of chronic ambient PM2.5 on life expectancy, which constitutes an important gauge of public human health status. Therefore, the aim of this study was to investigate the effects of reducing ambient PM2.5 levels in Taiwan on life expectancy there from 2000 to 2020. Officially reported island-wide annually average concentrations of ambient PM2.5, county-level life expectancies, and demographic and socioeconomic and proxy variable were collected for the prevalence of smoking from various national public agencies and organizations, since variables these might potentially confound life expectancy results. The relationship between changes in ambient PM2.5 levels and life expectancy were determined using linear regression. Data demonstrated that counties with greater reductions in ambient PM2.5 concentrations were associated with higher life expectancies. Adjusting for alterations in demographic and socioeconomic variables and proxy parameter, the prevalence of smoking data from a multiple regression model, it was found that a 0.3-year rise in life expectancy was noted for each 10 ug/m3 decrease in PM2.5 in those counties. Our findings show that reducing ambient PM2.5 levels play an important role for prolongation of life expectancy in Taiwan.

Although Taipei City has encountered a fall in ambient air pollutant levels since 1996, the year its mass rapid transit (MRT) system commenced operation, no apparent study investigated changes in risks of death attributed to respiratory, cardiovascular, and cerebrovascular diseases in Taipei during this 23-year period. In order to examine the relationship between MRT and occurrence of respiratory and cardiovascular illnesses attributed to air contaminants, exposure over the 23 year duration was subdivided into the following periods: reference period 1 (1992-1995); period 2 (1996-2004), a time when there was a total track length of 67 km; period 3 (2005-2015), when the total track length was lengthened to 131.1 km; and period 4 (2016-2020), when it was further extended to 146.2 km. Taichung City, no MRT system, was used as an external reference population. The effect of Taipei's MRT system on rates of cause-specific death rates was analyzed using robust generalized Poisson regression models. After adjusting for age-standardized rates (ASRs), a decrease in relative risks (RRs) was found for non-trauma death and respiratory disease from periods 2 to 4. Even though the RRs were greater than 1.0 for cardiovascular and cerebrovascular diseases for periods 2 to 4, a downward trend was still noted in these RRs in Taipei. These findings suggest a relationship exists between air pollutant exposure and mortality. In addition, data demonstrated that implementation of the MRT in Taipei exerted beneficial health effects as evidenced by lower mortality rates.

There are few apparent studies regarding the association between fine particulate matter (PM2.5) air pollution and development of depression. Data obtained from epidemiological studies are inconsistent and controversial. The aim of this case-crossover study was to examine the association between short-term exposure to PM2.5 alone and in combination with other pollutants and frequency of hospitalizations for depression from 2009 to 2013 in Taipei, Taiwan. In the single pollutant model without adjustment for other pollutants, 17% and 4% increase in admissions attributed to depression correlated with interquartile range (IQR) rise in PM2.5 levels was noted on warm and cool days, respectively. Data were also analyzed using two-pollutant models and it was found that on warm days, the association continued to be significant after including one of the following pollutants: sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3) or carbon monoxide (CO). On cool days, the significance was lost. In conclusion, the relationship between ambient outdoor PM2.5 exposure and rates of hospitalization for depression appeared to be temperature dependent in Taipei. Further research is needed to verify these observations as well as to distinguish the relative contributions of PM2.5 and temperature to development for hospital admissions for depression.

Background/Purposes: Human rhinovirus type C (HRV-C) has been associated with asthma exacerbation (AE) in children in several countries. However, in Taiwan the association between HRV, especially HRV-C, and AE in children has yet to be elucidated. We sought to investigate the prevalence of respiratory viruses in children with acute lower respiratory tract infection (ALRTI) in Taiwan and the association between different types of HRV and AE in children. Methods: This prospective study was conducted from 2011 to 2013, and enrolled children with ALRTI, including an asthma exacerbation group (AE; n = 28) and a Non-asthma group (n = 66). Viruses were detected by culture, reverse transcription-polymerase chain reaction, and molecular sequencing of nasopharyngeal swabs. Results: The prevalence of identified respiratory viruses was 78.6% in the AE group and 65.2% in the Non-asthma group. The prevalence rates of HRV and HRV-C were significantly higher in the AE group than in the Non-asthma group (67.9% vs. 33.3% in HRV, p = 0.002; and 50% vs. 15.2% in HRV-C, p < 0.001). Among the children with HRV, the prevalence of HRV-C (68.4%) was higher than that of the other types of HRV (31.6%, including HRV-A 26.3%, and HRV-B 5.3%) in the AE group but not in the Non-asthma group (40.9% vs. 59.1%). Conclusions: HRV is the most predominant viral infection responsible for pediatric AE in Taiwan, and HRV-C is responsible for more of these exacerbations than HRV-A or HRV-B. Copyright (C) 2018, Taiwan Society of Microbiology. Published by Elsevier Taiwan LLC.

Numerous epidemiologic studies demonstrated an association between an increase in levels of fine particles (particulate matter less than 2.5 um in diameter, PM2.5) and elevation in the number of hospital admissions for cardiovascular diseases. Air pollution levels including PM2.5 clearly decreased in Taipei City after the mass rapid transit (MRT) system began operations in 1996. The aim of this study was to investigate the extent of changes in the risk of daily hospital admissions for ischemic heart disease (IHD) over a 17-year period after the installation of a MRT system in Taipei. The full study was divided into Period 1 (1997-2000), total track length 65.1 km; Period 2 (2001-2008), total track length 75.8 km; and Period 3 (2009-2013), total track length 121.3 km. A time-stratified case-crossover analysis was conducted to estimate relative risk (RR) of hospital admissions for IHD for each 10 ug/m3 increase in PM2.5 for different periods. On cool days, the associated RR of IHD for Period 3 was consistently lower compared to period 2 in both our single- and two-pollutant models. However, the daily risk for IHD admissions was found to be significantly higher for period 3 compared to period 2 in our single-pollutant model and in our two-pollutant models (PM2.5+ SO2) on warm days. The basis for this difference is unknown. Data suggests that an MRT system may provide substantial health benefits, a finding that may be helpful to urban communities, urban planners, and public health specialists.

Epidemiologic studies reported an association between exposure to ambient air pollutants and increased mortality rate attributed to suicide and suicide attempts. The investigation sought to determine whether there is an association between short-term ambient ozone (O3) level exposure and daily hospital admissions for depression in Taipei from 2009 to 2013 using a time-stratified case-crossover design. In our single-pollutant model (with no adjustment for other pollutants), the % increase in daily hospital admissions for depression was 12% on warm days and 30% on cool days, per interquartile range (IQR) rise in O3 levels, respectively. Ozone levels were significantly correlated with daily number of depression admissions both on warm and cool days. In our two-pollutant models, O3 levels remained significant after adjusting for other air pollutants, including particulate matter (PM10, PM2.5), sulfur dioxide (SO2), nitrogen dioxide (NO2), and carbon monoxide (CO) both on warm and cool days. Although O3 levels tended to be higher on warm days, admissions for depression were higher on cool days, suggesting that the relationship between O3 concentrations and depression may be affected by temperature. Further study is needed to better understand these findings.