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Cited by 339Air Quality and Health ImpactsIndoor Air Quality and Microbial ExposureClimate Change and Health Impacts

Differentiating the effects of fine and coarse particles on daily mortality in Shanghai, China

Open access
Kan, Haidong, London, Stephanie J., Chen, Guohai, Zhang, Yunhui, Song, Guixiang, Zhao, Naiqing, Jiang, Lili, Chen, Bingheng·2007·Environment International
DOI 10.1016/j.envint.2006.12.001PMC PMC2094002
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Abstract

The findings on health effects of ambient fine particles (PM2.5) and coarse particles (PM10-2.5) remain inconsistent. In China, PM2.5 and PM10-2.5 are not the criteria air pollutants, and their monitoring data are scarce. There have been no epidemiological studies of health effects of PM2.5 and PM10-2.5 simultaneously in China. We conducted a time series study to examine the acute effects of PM2.5 and PM10-2.5 on daily mortality in Shanghai, China from Mar. 4, 2004 to Dec. 31, 2005. We used the generalized additive model (GAM) with penalized splines to analyze the mortality, air pollution and covariate data. The average concentrations of PM2.5 and PM10-2.5 were 56.4 microg/m3 and 52.3 microg/m3 in our study period, and PM2.5 constituted around 53.0% of the PM10 mass. Compared with the Global Air Quality Guidelines set by World Health Organization (10 microg/m3 for annual mean) and U.S. National Ambient Air Quality Standards (15 microg/m3 for annual mean), the PM2.5 level in Shanghai was much higher. We found that PM2.5 was associated with the death rates from all causes and from cardiorespiratory diseases in Shanghai. We did not find a significant effect of PM10-2.5 on mortality outcomes. A10 microg/m3 increase in the 2-day moving average (lag01) concentration of PM2.5 corresponded to 0.36% (95% CI 0.11%, 0.61%), 0.41% (95% CI 0.01%, 0.82%) and 0.95% (95% CI 0.16%, 1.73%) increase of total, cardiovascular and respiratory mortality. For PM10-2.5, the effects were attenuated and less precise. Our analyses provide the first statistically significant evidence in China that PM2.5 has an adverse effect on population health and strengthen the rationale for further limiting levels of PM2.5 in outdoor air in Shanghai.

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Written from the paper’s full text.

TL;DR

This time-series study in Shanghai found that fine particulate matter (PM2.5) was associated with increased daily all-cause, cardiovascular, and respiratory mortality, while coarse particles (PM10-2.5) showed no significant associations. The authors report the first statistically significant evidence in China that PM2.5 adversely affects population health.

Key findings

  • Over 668 days (Mar. 4, 2004–Dec. 31, 2005), mean PM2.5 was 56.4 µg/m³ and mean PM10-2.5 was 52.3 µg/m³; PM2.5 constituted about 53.0% of PM10 mass.
  • A 10 µg/m³ increase in lag01 PM2.5 was associated with 0.36% (95% CI 0.11%, 0.61%) higher total mortality, 0.41% (95% CI 0.01%, 0.82%) higher cardiovascular mortality, and 0.95% (95% CI 0.16%, 1.73%) higher respiratory mortality.
  • PM10-2.5 effects were attenuated and not statistically significant: total mortality 0.12% (95% CI −0.13%, 0.36%), cardiovascular 0.34% (95% CI −0.05%, 0.73%), respiratory 0.40% (95% CI −0.34%, 1.13%).
  • PM10 was significantly associated with total mortality (0.16%, 95% CI 0.02%, 0.30%) and cardiovascular mortality (0.31%, 95% CI 0.10%, 0.53%), but not respiratory mortality.

Methods

  • Time-series analysis using a generalized additive model (GAM) with penalized splines, log link, and Poisson error; adjusted for time trend, day of week, temperature, relative humidity, and ozone.
  • Mortality data came from the Shanghai Municipal Center of Disease Control and Prevention for nine urban districts; air pollution data came from a fixed-site Shanghai Environmental Monitoring Center station; PM10-2.5 was estimated by subtracting PM2.5 from PM10.
  • Primary exposure was the 2-day moving average (lag01) of particles; sensitivity analyses varied lag structures, degrees of freedom, and exclusion of extreme concentrations; analyses used R 2.1.1 with the MGCV package.

Limitations

  • The paper states that outdoor monitoring data were used to represent population exposure, which may introduce measurement error, generally biasing estimates downward, but personal exposure data were unavailable to quantify this.
  • The paper states that particle assessment came from one monitoring station, and the single-city, limited time period may have limited power to detect significant PM10-2.5 associations.
  • The paper states that only current-day weather was adjusted for and indoor particle sources were not considered; the text also makes evident that PM10-2.5 was estimated by subtraction rather than directly measured, and PM2.5/PM10-2.5 data were available for 661 of 668 days with no missing-data imputation.

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Integrity signals

Registry

Crossref · 10.1016/j.envint.2006.12.001

Cites

82 of 82 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 52 cited sources checked · 0 supported · 0 flagged

  • Findingown data
    § Abstract

    PM10-2.5 had no significant effect on mortality outcomes.

    “We did not find a significant effect of PM10-2.5 on mortality outcomes.”
    • Also stated in: § 4. Discussion · plain
      “We did not find significant effects of PM10-2.5 on mortality outcomes.”
    Quote in the paperSubstantial claim
  • Findingown data
    § Abstract

    A 10μg/m3 increase in the 2-day moving average (lag01) concentration of PM2.5 corresponded to a 0.36% (95%CI 0.11%, 0.61%) increase in total mortality.

    “A10µg/m3 increase in the 2-day moving average (lag01) concentration of PM2.5 corresponded to 0.36% (95%CI 0.11%, 0.61%), 0.41% (95% CI 0.01%, 0.82%) and 0.95% (95% CI 0.16%, 1.73%) increase of total, cardiovascular and respiratory mortality.”
    • Also stated in: § 3.2 Regression results · plain
      “total mortality increased 0.16% (95%CI 0.02% - 0.30%) for PM10, 0.36% (95%CI 0.11% - 0.61%) for PM2.5 and 0.12% (95%CI -0.13% - 0.36%) for PM10-2.5.”
    Quote in the paperSubstantial claim
  • Findingown data
    § Abstract

    A 10μg/m3 increase in the 2-day moving average (lag01) concentration of PM2.5 corresponded to a 0.95% (95% CI 0.16%, 1.73%) increase in respiratory mortality.

    “A10µg/m3 increase in the 2-day moving average (lag01) concentration of PM2.5 corresponded to 0.36% (95%CI 0.11%, 0.61%), 0.41% (95% CI 0.01%, 0.82%) and 0.95% (95% CI 0.16%, 1.73%) increase of total, cardiovascular and respiratory mortality.”
    • Also stated in: § 3.2 Regression results · plain
      “Respiratory mortality 0.95 0.16 to 1.73”
    Quote in the paperSubstantial claim
  • Findingown data
    § Abstract

    A 10μg/m3 increase in the 2-day moving average (lag01) concentration of PM2.5 corresponded to a 0.41% (95% CI 0.01%, 0.82%) increase in cardiovascular mortality.

    “A10µg/m3 increase in the 2-day moving average (lag01) concentration of PM2.5 corresponded to 0.36% (95%CI 0.11%, 0.61%), 0.41% (95% CI 0.01%, 0.82%) and 0.95% (95% CI 0.16%, 1.73%) increase of total, cardiovascular and respiratory mortality.”
    • Also stated in: § 3.2 Regression results · plain
      “Cardiovascular mortality 0.41 0.01 to 0.82”
    Quote in the paperSubstantial claim
  • Findingcitation
    § 4. Discussion

    In Shanghai, PM2.5 was more strongly associated with cardio-respiratory mortality than with all-cause mortality.

    “Our study confirmed previous findings that fine particle was more strongly associated with cardio-respiratory mortality than with all-cause mortality risk (Ostro et al. 2006; Stolzel et al. 2006; Wichmann et al. 2000).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Ostro et al. 2006 source

      Not checked in the free run.

    • cites Stolzel et al. 2006

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    • cites Wichmann et al. 2000

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  • May combine two claims. 25
  • Classified as probably not a substantial claim. 26

  • May combine two claims.

    Findingown data
    § Abstract

    The average concentrations of PM2.5 and PM10-2.5 were 56.4μg/m3 and 52.3μg/m3 in the study period.

    “The average concentrations of PM2.5 and PM10-2.5 were 56.4µg/m3 and 52.3µg/m3 in our study period”
    • Also stated in: § 3.1 Data description · plain
      “During our research period, the mean daily concentrations of PM2.5 and PM10-2.5 were 56.4µg/m3 and 52.3µg/m3 respectively.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § Abstract

    PM2.5 constituted around 53.0% of the PM10 mass.

    “PM2.5 constituted around 53.0% of the PM10 mass.”
    • Also stated in: § 3.1 Data description · plain
      “the ratio of daily concentrations of PM2.5 and PM10 ranged from 12% to 97%, with an average of 53.0%.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Abstract

    PM2.5 was associated with the death rates from all causes and from cardio-respiratory diseases in Shanghai.

    “We found that PM2.5 was associated with the death rates from all causes and from cardio-respiratory diseases in Shanghai.”
    • Also stated in: § 4. Discussion · plain
      “We found that the current level of PM2.5 was associated with elevated death rates from all causes and from cardio-respiratory diseases in Shanghai.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § Abstract

    For PM10-2.5, the effects on mortality were attenuated and less precise.

    “For PM10-2.5, the effects were attenuated and less precise.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § Abstract

    The PM2.5 level in Shanghai was much higher than the WHO Global Air Quality Guidelines (10μg/m3 annual mean) and U.S. National Ambient Air Quality Standards (15μg/m3 annual mean).

    “Compared with the Global Air Quality Guidelines set by World Health Organization (10µg/m3 for annual mean) and U.S. National Ambient Air Quality Standards (15µg/m3 for annual mean), the PM2.5 level in Shanghai was much higher.”
    • Also stated in: § 3.1 Data description · plain
      “Compared with the Global Air Quality Guidelines set by World Health Organization (10µg/m3 for annual mean and 25µg/m3 for 24-hour mean) and U.S. National Ambient Air Quality Standards (15µg/m3 for annual mean and 35µg/m3 for 24-hour mean), the PM2.5 level in Shanghai was much higher.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § 4. Discussion

    In Shanghai, PM2.5 was significantly associated with total and cardio-respiratory mortality.

    “Consistent with most prior studies (Englert 2004), we found significant effects of PM2.5 on both total and cardio-respiratory outcomes.”
    • Also stated in: § 5. Conclusions · plain
      “In summary, we found significant associations of daily mortality with PM2.5, but not with PM10-2.5 in Shanghai.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The exposure-response curves for PM2.5 and total and cardiovascular mortality were positive nonlinear relationships, with risks not increasing monotonically and curves becoming nonlinear and flat at lower and higher concentrations.

    “For total and cardiovascular mortality, the exposure–response curves associated with PM2.5 exposure present positive nonlinear relationships, although the risks did not increase monotonically. The curves tend to become nonlinear and flat at lower and higher concentrations (Figures 2a and 2b).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    PM10-2.5 was not significantly associated with total and respiratory mortality, but was marginally associated with cardiovascular mortality.

    “We did not find significant associations of PM10-2.5 with total and respiratory mortality outcomes; however, PM10-2.5 was marginally associated with cardiovascular mortality (Table 3).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The effects of PM2.5 on total and cardiovascular mortality were statistically significant in single-day lag 0 and multi-day lag 01.

    “The effects of PM2.5 on total and cardiovascular mortality were statistically significant in single-day lag 0 and multi-day lag 01 (Figures 1a and 1b).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    For respiratory mortality, the effect of PM2.5 was significant on single-day lag 1 and multi-day lag 01.

    “For respiratory mortality, the effect of PM2.5 was significant on single-day lag 1 and multi-day lag 01 (Figure 1c).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    For total and cardiovascular mortality, there were significant effects of both PM10 and PM2.5; for respiratory mortality, only PM2.5 had a significant association.

    “For total and cardiovascular mortality, we found significant effects of both PM10 and PM2.5; for respiratory mortality, only PM2.5 had a significant association.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § 4. Discussion

    In Shanghai, PM10-2.5 was not significantly associated with total or respiratory mortality.

    “Of note, we did not find a significant effect of PM10-2.5 on either total or respiratory mortality.”
    • Also stated in: § 5. Conclusions · plain
      “In summary, we found significant associations of daily mortality with PM2.5, but not with PM10-2.5 in Shanghai.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Premisecitation
    § 1. Introduction

    Short-term exposure to outdoor air pollution contributes to increased cardiorespiratory mortality and morbidity.

    “Numerous epidemiological studies during the past 20 years have confirmed that short-term exposure to outdoor air pollution contributes to increased cardiorespiratory mortality and morbidity (Brunekreef and Holgate 2002).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Brunekreef and Holgate 2002

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S1 (asserted).

    Premisereasoning
    § 1. Introduction

    PM2.5 and PM10-2.5 may have different biologic effects and toxicity.

    “These characteristics, combined with a different pattern of deposition in the lung, support the hypothesis that PM2.5 and PM10-2.5 may have different biologic effects and toxicity.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductcitation

    O3 was controlled in the regression models because a previous study showed that O3 had an independent effect on daily mortality in Shanghai and the correlation between PM and O3 was low.

    “To examine the independent effects of PM2.5 and PM10-2.5, O3 was also controlled in the regression models because our previous study showed that O3 had independent effect on daily mortality in Shanghai and the correlation between PM and O3 was low (Zhang et al. 2006).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Zhang et al. 2006 source

      Not checked in the free run.

  • May combine two claims.

    Study design and conductcitation

    SO2 and NO2 were not adjusted for because PM was highly correlated with SO2 and NO2 in Shanghai and simultaneously entering SO2 (or NO2) into the models can yield unstable parameter estimates when the pollutants involved suffer high inter-correlation.

    “We did not adjust for sulfur dioxide (SO2) and nitrogen dioxide (NO2) in our regression models because PM was highly correlated with SO2 and NO2 in Shanghai (Zhang et al. 2006) and simultaneously entering SO2 (or NO2) into the models can yield unstable parameter estimates when the pollutants involved suffer high inter-correlation (Roberts 2006).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites Zhang et al. 2006 source

      Not checked in the free run.

    • cites Roberts 2006 source

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data

    Only actual collected data were used, and missing data of PM2.5 and PM10-2.5 were not filled in.

    “We only used the actual collected data, and did not fill in the missing data of PM2.5 and PM10-2.5.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductreasoning
    § 4. Discussion

    The measurement was conducted at a fixed-site monitoring station under China National Quality Control, mandated not to be in direct proximity to traffic, industrial sources, buildings or residential sources of emissions; thus the monitoring results reflect the background urban particle level in Shanghai.

    “In addition, our measurement was conducted at a fix-site monitoring station under China National Quality Control. The station is mandated to not be in direct proximity to traffic, industrial sources, buildings or residential sources of emissions from the burning of coal-, waste-, or oil. Thus our monitoring results reflect the background urban particle level in Shanghai.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductown data
    § 4. Discussion

    The study used data from continuous monitoring of PM2.5 and PM10-2.5 in Shanghai and had data for 668 consecutive days.

    “We used data from the continuous monitoring of PM2.5 and PM10-2.5 in Shanghai and had data for 668 consecutive days.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Sensitivity analysis excluded days with extremely high or low particle concentrations (the highest and lowest 1% values).

    “In addition to the whole-period (Mar. 4, 2004 to Dec. 31, 2005) analysis, we also did sensitivity analysis excluding days with extremely high or low particle concentrations (the highest and lowest 1% values).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation
    § 1. Introduction

    Fewer studies have evaluated associations with PM10-2.5 than with PM2.5 or PM10, largely due to lack of monitoring data.

    “While many epidemiological studies have reported associations of mortality and morbidity with ambient PM2.5 or PM10 (Pope and Dockery 2006), fewer studies have evaluated associations with PM10-2.5, which is largely due to lack of monitoring data.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Pope and Dockery 2006

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    A smoothing function was used to graphically analyze the relationship between mortality and particles because the assumption of linearity between the log of mortality and particles may not be justified.

    “Because the assumption of the linearity between the log of mortality and particles may not be justified, we used the smoothing function to graphically analyze their relations (Bell et al. 2006; Daniels et al. 2004).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Bell et al. 2006 source

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    • cites Daniels et al. 2004

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    Study design and conductnone given

    For calculation of 24-hour average concentration of PM10, PM2.5 and PM10-2.5, at least 75% of the one-hour values on that particular day have to be available.

    “For the calculation of 24-hour average concentration of PM10, PM2.5 and PM10-2.5, at least 75% of the one-hour values on that particular day have to be available.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning
    § 4. Discussion

    Shanghai offers advantages for the investigation of the particle-mortality relationship because the study area is densely populated, a lower proportion of residents have access to or use air conditioning, and monitored air pollution data from summer months may be more closely associated with average population exposures than in North America.

    “Shanghai offers advantages for the investigation of the particle-mortality relationship. Our study area, nine urban districts of Shanghai, is densely populated. More than six-million permanent residents reside within 279 square kilometers. In addition, compared with the residents in North America, a lower proportion of Shanghai residents have access to or use air conditioning. Thus, the monitored”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § 1. Introduction

    Particulate matter has the most consistent association with mortality among pollutants in the ambient mix.

    “Among the pollutants in the ambient mix, particulate matter (PM) has the most consistent association with mortality (Bell et al. 2004).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Bell et al. 2004

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  • May combine two claims.

    Study design and conductown data

    The regression results did not change significantly after excluding days with extremely high and low concentrations, although the estimated effects of PM2.5 and PM10-2.5 increased slightly.

    “Generally, the regression results did not change significantly, although the estimated effects of PM2.5 and PM10-2.5 increased slightly after excluding extreme concentrations.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation
    § 4. Discussion

    These studies measured PM2.5 concentrations weekly, with monitoring duration no more than one year.

    “These studies measured PM2.5 concentrations weekly, with monitoring duration no more than one year.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § 4. Discussion

    Another advantage of the study is the ability to use cumulative exposure to PM, which is not always possible in the United States where PM is often measured every few days.

    “Another advantage of our study is the ability to use cumulative exposure to PM, which is not always possible in the United States where PM is often measured every few days.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    Sensitivity analysis tested the impact of degrees of freedom selection on the regression results.

    “Given that it is not easy to determine the optimal values of df for time trend and weather conditions in the models whether from statistical or biological plausibility perspectives, we did sensitivity analysis to test the impact of df selection on the regression results.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductown data

    Changes in degrees of freedom for time trend (within 5-25) and weather conditions (within 3-12) did not affect the regression results much, suggesting that the findings on the effects of particle concentrations on total mortality are relatively robust.

    “Clearly, the changes of df for time trend (within the range of 5-25) and for weather conditions (within the range of 3-12) do not affect the regression results much, which suggest that our findings on the effects of particle concentrations on total morality are relatively robust in this respect.”
    Quote in the paperSubstantial claim

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    Premisecitation
    § 4. Discussion

    The measurement error would generally tend to bias estimates downward.

    “The resulting measurement error may have implications for interpreting the effect of particles (Zeger et al. 2000), although a study suggested that this measurement error would generally tend to bias estimates downward (Samet et al. 2000).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Samet et al. 2000

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    Premisecitation
    § 4. Discussion

    PM2.5 can produce oxidative stress, in part because of lung inflammation.

    “Subjects who develop COPD, an important cause of respiratory mortality, may have weakened antioxidant defenses (Rahman et al. 1996), and PM2.5 can produce oxidative stress, in part because of lung inflammation (Dagher et al. 2005; Zeka et al. 2006).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Dagher et al. 2005 source

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    • cites Zeka et al. 2006 source

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    Interpretationcitation
    § 4. Discussion

    These findings provide possible pathways by which PM2.5 can affect the cardiovascular system.

    “These findings provide possible pathways by which PM2.5 can affect the cardiovascular system.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation
    § 4. Discussion

    In vivo pulmonary toxicity of urban particles varies with size, with greatest toxicity from particles <1.7 μm and lowest from those >3.5 μm.

    “For instance, Costa et al found that the in vivo pulmonary toxicity of urban particles varied with size, with the greatest toxicity from particles <1.7µm and the lowest toxicity from those >3.5µm (Costa and Dreher 1997).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Costa and Dreher 1997

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    Premisecitation
    § 4. Discussion

    The acute effect of PM on daily mortality is robust to the lag structure of weather conditions.

    “We only adjusted for the current-day weather conditions; previous study suggests that the acute effect of PM on daily mortality is robust to the lag structure of weather conditions (Samet et al. 2000).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Samet et al. 2000

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    Premisecitation
    § 4. Discussion

    Ambient particles have been associated with increased plasma viscosity.

    “For example, ambient particles have been associated with increased plasma viscosity (Peters et al. 1997), sequestration of red cells in the circulation (Seaton et al. 1999), and indicators of cardiac autonomic dysfunction including increased heart rate, decreased heart rate variability, and increased cardiac arrhythmias (Dockery 2001).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Peters et al. 1997 source

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    Premisecitation
    § 4. Discussion

    The daily population average concentrations of fine particles derived from indoor sources are approximately independent of ambient levels.

    “However, some studies suggested that the daily population average concentrations of fine particles derived from indoor sources are approximately independent of ambient levels (Wilson and Suh 1997).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Wilson and Suh 1997

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  • May combine two claims.

    Interpretationreasoning
    § 4. Discussion

    Local PM level, population sensitivity, age distribution, and particle components may strongly affect exposure-response relationships.

    “Local PM level, population sensitivity to PM, age distribution and especially different particle components may strongly affect the exposure-response relationships.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § 4. Discussion

    Ambient particles have been associated with indicators of cardiac autonomic dysfunction including increased heart rate, decreased heart rate variability, and increased cardiac arrhythmias.

    “For example, ambient particles have been associated with increased plasma viscosity (Peters et al. 1997), sequestration of red cells in the circulation (Seaton et al. 1999), and indicators of cardiac autonomic dysfunction including increased heart rate, decreased heart rate variability, and increased cardiac arrhythmias (Dockery 2001).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Dockery 2001 source

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § 4. Discussion

    Ambient particles have been associated with sequestration of red cells in the circulation.

    “For example, ambient particles have been associated with increased plasma viscosity (Peters et al. 1997), sequestration of red cells in the circulation (Seaton et al. 1999), and indicators of cardiac autonomic dysfunction including increased heart rate, decreased heart rate variability, and increased cardiac arrhythmias (Dockery 2001).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Seaton et al. 1999 source

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § 4. Discussion

    Various regression models and parameter settings affect regression coefficients.

    “Earlier simulation studies have shown that various regression models and parameter setting in the models (e.g. df selection, convergence criteria) would affect the regression coefficients (Dominici et al. 2002; Peng et al. 2006).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Dominici et al. 2002 source

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    • cites Peng et al. 2006 source

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  • May combine two claims.

    Interpretationcitation
    § 4. Discussion

    The null association of PM10-2.5 with mortality is consistent with most prior studies but in contrast to several others.

    “This is consistent with most prior studies (Anderson et al. 2001; Fairley 1999; Klemm and Mason 2000; Klemm et al. 2000; Lipfert et al. 2000; Ostro et al. 2000; Schwartz et al. 1996; Villeneuve et al. 2003), but in contrast to several others (Burnett et al. 2000; Cifuentes et al. 2000; Mar et al. 2000).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Anderson et al. 2001 source

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    • cites Fairley 1999 source

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    • cites Klemm and Mason 2000

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    Premisecitation
    § 4. Discussion

    COPD patients may be susceptible to particulate air pollution because obstructive airways disease leads to enhanced deposition of inhaled particles.

    “COPD patients may also be susceptible to particulate air pollution because obstructive airways disease leads to enhanced deposition of inhaled particles (Kim and Kang 1997).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Kim and Kang 1997

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation
    § 4. Discussion

    Failure to measure indoor sources will not introduce further bias in the estimated effects of ambient particles when indoor fine particle concentrations are independent of ambient levels.

    “When this is true, failure to measure indoor sources will not introduce further bias in the estimated effects of ambient particles (Zeger et al. 2000).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Zeger et al. 2000 source

      Not checked in the free run.

  • May combine two claims.

    Study design and conductown data
    § 4. Discussion

    The data were limited by virtue of the single city and limited time period.

    “Compared with studies in Europe and North America, the data we collected were also limited by virtue of the single city and limited time period.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § 4. Discussion

    Subjects who develop COPD may have weakened antioxidant defenses.

    “Subjects who develop COPD, an important cause of respiratory mortality, may have weakened antioxidant defenses (Rahman et al. 1996), and PM2.5 can produce oxidative stress, in part because of lung inflammation (Dagher et al. 2005; Zeka et al. 2006).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Rahman et al. 1996 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation
    § 4. Discussion

    The resulting measurement error may have implications for interpreting the effect of particles.

    “The resulting measurement error may have implications for interpreting the effect of particles (Zeger et al. 2000), although a study suggested that this measurement error would generally tend to bias estimates downward (Samet et al. 2000).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Zeger et al. 2000 source

      Not checked in the free run.

47 of 47

  • The paper relies on this without support.

    There have been no epidemiological studies of health effects of PM2.5 and PM10-2.5 simultaneously in China.

    “There have been no epidemiological studies of health effects of PM2.5 and PM10-2.5 simultaneously in China.”

  • The paper relies on this without support.

    There have been no epidemiological studies investigating the health effect of PM10-2.5 in China.

    “To our knowledge, there have been no epidemiological studies investigating the health effect of PM10-2.5 in China.”

  • The paper relies on this without support.

    In China, PM2.5 and PM10-2.5 are not the criteria air pollutants.

    “In China, PM2.5 and PM10-2.5 are not the criteria air pollutants, and their monitoring data are scarce.”

  • The paper relies on this without support.

    Particle levels in Shanghai are much higher than in developed countries.

    “Compared with developed countries, particle levels in Shanghai are much higher.”
    “Compared with developed countries, the level of PM2.5 in Shanghai is much higher.”

  • The paper relies on this without support.

    The composition of the motor vehicle fleet in developed countries differs substantially from that in Shanghai.

    “In addition, the composition of the motor vehicle fleet in developed countries differs substantially from that in Shanghai.”

  • The paper relies on this without support.

    Most prior air pollution time-series studies have been based on the GAM model in S-PLUS.

    “Most prior air pollution time-series studies have been based on the GAM model in S-PLUS.”

  • The paper relies on this without support.

    PM10-2.5 is typically mechanically generated by crushing or grinding, and is often dominated by re-suspended dusts and crustal material from paved or unpaved roads or from construction, farming, and mining activities.

    “PM10-2.5 is typically mechanically generated by crushing or grinding, and is often dominated by re-suspended dusts and crustal material from paved or unpaved roads or from construction, farming, and mining activities.”

  • The paper relies on this without support.

    Generally, nature-generated particles are less toxic to the cardio-respiratory system than combustion-related particles, such as oil fly ash particles.

    “Generally, these nature-generated particles are less toxic to the cardio-respiratory system than combustion-related particles, such as oil fly ash particles.”

  • The paper relies on this without support.

    In Shanghai, little or no indoor air monitoring data are available.

    “In Shanghai, little or no indoor air monitoring data are available.”
9 of 9

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Conflicting study-area sizes

    Minor

    The methods give the nine urban districts an area of 289 km2, while the discussion gives 279 square kilometers for the same study area.

  • Tables end one day before the stated study period

    Minor

    The methods state that mortality data run through December 31, 2005, but the summary-statistics table labels its period as ending December 30, 2005. The correlation table uses the December 30 end date as well.

  • Particle measurements are not reported for all 668 days

    Minor

    The discussion says it had PM2.5 and PM10-2.5 data for 668 consecutive days, whereas Table 1 reports 661 observations for each measure.

  • Conflicting Chinese PM10 limits

    Minor

    The introduction gives the daily and annual PM10 limits as 50 and 150 μg/m3, respectively; the results give them as 150 and 100 μg/m3, respectively.

4 of 4

Cites

Flagged first, then by citations

1 of the 83 references couldn’t be matched to a known paper.

Cited by

Sorted by citations

Related

Authors
Kan, H., London, S. J., Chen, G., Zhang, Y., Song, G., Zhao, N., Jiang, L., & Chen, B.
Affiliations
  • Fudan University (CN)
  • National Institute of Environmental Health Sciences (US)
  • Shanghai Municipal Center For Disease Control Prevention (CN)
Corresponding author
Kan, Haidong
ORCID
Venue
Environment International
Publisher
Elsevier BV
Published
2007-04
Volume
33
Issue
3
Pages
376-384
ISSN
0160-4120 (ISSN-L)
DOI
10.1016/j.envint.2006.12.001
PMC
PMC2094002
OpenAlex
W2138898408
Semantic Scholar
efe61f85b1a1287012c7318b32129ae3a7a47a46
Cited by
339
References
83
Citations by year
2026: 1 · 2025: 6 · 2024: 10 · 2023: 5 · 2022: 18 · 2021: 18 · 2020: 22 · 2019: 27 · 2018: 33 · 2017: 19 · 2016: 25 · 2015: 27 · 2014: 27 · 2013: 26 · 2012: 17
FWCI
9.34
Type
journal article
Language
en
Open access
Licence
www.elsevier.com/tdm/userlicense/1.0/ (tdm)
Locations
  • Environment International (publishedVersion)
  • PubMed (publishedVersion)
  • PubMed Central (acceptedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion)
Funders
  • National Institutes of Health
  • National Institute of Environmental Health Sciences (Z01ES043012)
Topics
  • Physical Sciences › Environmental Science › Health, Toxicology and Mutagenesis › Air Quality and Health Impacts
  • Physical Sciences › Environmental Science › Health, Toxicology and Mutagenesis › Indoor Air Quality and Microbial Exposure
  • Physical Sciences › Environmental Science › Health, Toxicology and Mutagenesis › Climate Change and Health Impacts
Keywords
PM2.5, PM2.5-10, coarse particles, air pollution health effects, daily mortality, cardiovascular mortality, respiratory mortality, all-cause mortality, Shanghai, air quality guidelines, air quality standards
MeSH terms
Air Pollutants, Cardiovascular Diseases, China, Cities, Environmental Exposure, Humans, Mortality, Ozone, Particle Size, Respiratory Tract Diseases, Urban Health, Particulate Matter

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Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-10.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-10.

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