A meta-analysis and multisite time-series analysis of the differential toxicity of major fine particulate matter constituents.
Ontology highlight
ABSTRACT:
SUBMITTER: Levy JI
PROVIDER: S-EPMC3491972 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:Exposure to fine particles (PM2.5) during pregnancy has been linked to lower birth weight; however, the chemical composition of PM2.5 varies widely. The health effects of PM2.5 constituents are unknown.We investigated whether PM2.5 mass, constituents, and sources are associated with birth weight for term births. PM2.5 filters collected in 3 Connecticut counties and 1 Massachusetts county from August 2000 through February 2004 were analyzed for more than 50 elements. Source apportionment was used to estimate daily contributions of PM2.5 sources, including traffic, road dust/crustal, oil combustion, salt, and regional (sulfur) sources. Gestational and trimester exposure to PM2.5 mass, constituents, and source contributions were examined in relation to birth weight and risk of small-at-term birth (term birth <2500 g) for 76,788 infants.Road dust and related constituents such as silicon and aluminum were associated with lower birth weight, as were the motor-vehicle-related species such as elemental carbon and zinc, and the oil-combustion-associated elements vanadium and nickel. An interquartile range increase in exposure was associated with low birthweight for zinc (12% increase in risk), elemental carbon (13%), silicon (10%), aluminum (11%), vanadium (8%), and nickel (11%). Analysis by trimester showed effects of third-trimester exposure to elemental carbon, nickel, vanadium, and oil-combustion PM2.5.Exposures of pregnant women to higher levels of certain PM2.5 chemical constituents originating from specific sources are associated with lower birth weight.
| S-EPMC3055585 | biostudies-literature
Project description:BackgroundNumerous studies have linked fine particles [? 2.5 µm in aerodynamic diameter (PM(2.5))] and health. Most studies focused on the total mass of the particles, although the chemical composition of the particles varies substantially. Which chemical components of fine particles that are the most harmful is not well understood, and research on the chemical composition of PM(2.5) and the components that are the most harmful is particularly limited in Asia.ObjectivesWe characterized PM(2.5) chemical composition and estimated the effects of cause-specific mortality of PM(2.5) mass and constituents in Seoul, Korea. We compared the chemical composition of particles to those of the eastern and western United States.MethodsWe examined temporal variability of PM(2.5) mass and its composition using hourly data. We applied an overdispersed Poisson generalized linear model, adjusting for time, day of week, temperature, and relative humidity to investigate the association between risk of mortality and PM(2.5) mass and its constituents in Seoul, Korea, for August 2008 through October 2009.ResultsPM(2.5) and chemical components exhibited temporal patterns by time of day and season. The chemical characteristics of Seoul's PM(2.5) were more similar to PM(2.5) found in the western United States than in the eastern United States. Seoul's PM(2.5) had lower sulfate (SO(4)) contributions and higher nitrate (NO(3)) contributions than that of the eastern United States, although overall PM(2.5) levels in Seoul were higher than in the United States. An interquartile range (IQR) increase in magnesium (Mg) (0.05 ?g/m³) was associated with a 1.4% increase (95% confidence interval: 0.2%, 2.6%) in total mortality on the following day. Several components that were among the largest contributors to PM(2.5) total mass--NO(3), SO(4), and ammonium (NH(4))--were moderately associated with same-day cardiovascular mortality at the p < 0.10 level. Other components with smaller mass contributions [Mg and chlorine (Cl)] exhibited moderate associations with respiratory mortality on the following day (p < 0.10).ConclusionsOur findings link PM(2.5) constituents with mortality and have implications for policy making on sources of PM(2.5) and on the relevance of PM(2.5) health studies from other areas to this region.
| S-EPMC3385433 | biostudies-literature
Project description:BACKGROUND:The link between PM2.5 exposure and adverse health outcomes is well documented from studies across the world. However, the reported effect estimates vary across studies, locations and constituents. We aimed to conduct a meta-analysis on associations between short-term exposure to PM2.5 constituents and mortality using city-specific estimates, and explore factors that may explain some of the observed heterogeneity. METHODS:We systematically reviewed epidemiological studies on particle constituents and mortality using PubMed and Web of Science databases up to July 2015.We included studies that examined the association between short-term exposure to PM2.5 constituents and all-cause, cardiovascular, and respiratory mortality, in the general adult population. Each study was summarized based on pre-specified study key parameters (e.g., location, time period, population, diagnostic classification standard), and we evaluated the risk of bias using the Office of Health Assessment and Translation (OHAT) Method for each included study. We extracted city-specific mortality risk estimates for each constituent and cause of mortality. For multi-city studies, we requested the city-specific risk estimates from the authors unless reported in the article. We performed random effects meta-analyses using city-specific estimates, and examined whether the effects vary across regions and city characteristics (PM2.5 concentration levels, air temperature, elevation, vegetation, size of elderly population, population density, and baseline mortality). RESULTS:We found a 0.89% (95% CI: 0.68, 1.10%) increase in all-cause, a 0.80% (95% CI: 0.41, 1.20%) increase in cardiovascular, and a 1.10% (95% CI: 0.59, 1.62%) increase in respiratory mortality per 10?g/m3 increase in PM2.5. Accounting for the downward bias induced by studies of single days, the all-cause mortality estimate increased to 1.01% (95% CI: 0.81, 1.20%). We found significant associations between mortality and several PM2.5 constituents. The most consistent and stronger associations were observed for elemental carbon (EC) and potassium (K). For most of the constituents, we observed high variability of effect estimates across cities. CONCLUSIONS:Our meta-analysis suggests that (a) combustion elements such as EC and K have a stronger association with mortality, (b) single lag studies underestimate effects, and (c) estimates of PM2.5 and constituents differ across regions. Accounting for PM mass in constituent's health models may lead to more stable and comparable effect estimates across different studies. SYSTEMATIC REVIEW REGISTRATION:PROSPERO: CRD42017055765.
| S-EPMC5689473 | biostudies-literature
Project description:Background:Maternal exposure to fine particulate air pollution (PM2.5) during pregnancy has been linked to lower newborn birthweight, making it a toxic exposure because lower birthweight is a risk factor for chronic disease and mortality. However, the toxicity of major constituents of PM2.5 and how they compare to each other remain uncertain. Methods:We assigned address-specific exposure to PM2.5, elemental carbon (EC), organic carbon (OC), nitrate, and sulfate averaged over the entire period of pregnancy for each birth in Massachusetts from 2001 to 2012 using a high-resolution exposure model. Using multivariate regression adjusted for total PM2.5, we estimated the relative toxicity of each constituent on continuous birthweight. Results:EC was more toxic per interquartile range increase compared with remaining PM2.5 in single constituent models that estimated the effect of a constituent with adjustment for PM2.5. OC, nitrate, and sulfate were each less toxic than their respective remaining PM2.5 per interquartile range increase. When all constituents and total PM2.5 were included in the same model, EC was most toxic, followed by nitrate, then OC and sulfate with similar toxicities. Sensitivity analyses using term low birth weight and small for gestational age also showed that EC was most detrimental as did averaging exposures over the third trimester of pregnancy. Scaling to unit mass increases also showed EC to be most toxic. Conclusion:Four major constituents of PM2.5 had different relative toxicities on continuous birthweight. Our findings suggest that EC was most toxic, followed by nitrate, OC, and sulfate.
| S-EPMC6571180 | biostudies-literature
Project description:BackgroundAlthough ambient fine particulate matter (PM(2.5); particulate matter ? 2.5 µm in aerodynamic diameter) has been linked to adverse human health effects, the chemical constituents that cause harm are unknown. To our knowledge, the health effects of PM(2.5) constituents have not been reported for a developing country.ObjectivesWe examined the short-term association between PM(2.5) constituents and daily mortality in Xi'an, a heavily polluted Chinese city.MethodsWe obtained daily mortality data and daily concentrations of PM(2.5), organic carbon (OC), elemental carbon (EC), and 10 water-soluble ions for 1 January 2004 through 31 December 2008. We also measured concentrations of fifteen elements 1 January 2006 through 31 December 2008. We analyzed the data using overdispersed generalized linear Poisson models.ResultsDuring the study period, the mean daily average concentration of PM(2.5) in Xi'an was 182.2 µg/m³. Major contributors to PM(2.5) mass included OC, EC, sulfate, nitrate, and ammonium. After adjustment for PM(2.5) mass, we found significant positive associations of total, cardiovascular, or respiratory mortality with OC, EC, ammonium, nitrate, chlorine ion, chlorine, and nickel for at least one lag period. Nitrate demonstrated stronger associations with total and cardiovascular mortality than PM(2.5) mass. For a 1-day lag, interquartile range increases in PM(2.5) mass and nitrate (114.9 and 15.4 µg/m³, respectively) were associated with 1.8% [95% confidence interval (CI): 0.8%, 2.8%] and 3.8% (95% CI: 1.7%, 5.9%) increases in total mortality.ConclusionsOur findings suggest that PM(2.5) constituents from the combustion of fossil fuel may have an appreciable influence on the health effects attributable to PM(2.5) in Xi'an.
| S-EPMC3295342 | biostudies-literature
Project description:Limited evidence is available on the effects of various fine particulate matter (PM2.5) components on inflammatory cytokines and DNA methylation. We examined whether 16 PM2.5 components are associated with changes in four blood biomarkers, that is, tumor necrosis factor-? (TNF-?), soluble cluster of differentiation 40 ligand (sCD40L), soluble intercellular adhesion molecule-1 (sICAM-1), and fibrinogen, as well as their corresponding DNA methylation levels in a panel of 36 healthy college students in Shanghai, China. We used linear mixed-effect models to evaluate the associations, with controls of potential confounders. We further conducted mediation analysis to evaluate the potential mediation effects of components on inflammatory markers through change in DNA methylation. We observed that several components were consistently associated with TNF-? and fibrinogen as well as their DNA hypomethylation. For example, an interquartile range increase in personal exposure to PM2.5-lead (Pb) was associated with 65.20% (95% CI: 37.07, 99.10) increase in TNF-? and 2.66 (95% CI: 37.07, 99.10) decrease in TNF-? methylation, 30.51% (95% CI: 0.72, 69.11) increase in fibrinogen and 1.25 (95% CI: 0.67, 1.83) decrease in F3 methylation. PM2.5 components were significantly associated with sICAM-1 methylation but not with sICAM-1 protein. DNA methylation mediated 19.89%-41.75% of the elevation in TNF-? expression by various PM2.5 constituents. Our findings provide clues that personal PM2.5 constituents exposure may contribute to increased systemic inflammation through DNA hypomethylation.
| S-EPMC7092684 | biostudies-literature
Project description:BackgroundEpidemiological studies have examined the association between PM2.5 and mortality, but uncertainty remains about the seasonal variations in PM2.5-related effects and the relative importance of species.ObjectivesWe estimated the effects of PM2.5 species on mortality and how infiltration rates may modify the association.MethodsUsing city-season specific Poisson regression, we estimated PM2.5 effects on approximately 4.5 million deaths for all causes, cardiovascular disease (CVD), myocardial infarction (MI), stroke, and respiratory diseases in 75 U.S. cities for 2000-2006. We added interaction terms between PM2.5 and monthly average species-to-PM2.5 proportions of individual species to determine the relative toxicity of each species. We combined results across cities using multivariate meta-regression, and controlled for infiltration.ResultsWe estimated a 1.18% (95% CI: 0.93, 1.44%) increase in all-cause mortality, a 1.03% (95% CI: 0.65, 1.41%) increase in CVD, a 1.22% (95% CI: 0.62, 1.82%) increase in MI, a 1.76% (95% CI: 1.01, 2.52%) increase in stroke, and a 1.71% (95% CI: 1.06, 2.35%) increase in respiratory deaths in association with a 10-?g/m3 increase in 2-day averaged PM2.5 concentration. The associations were largest in the spring. Silicon, calcium, and sulfur were associated with more all-cause mortality, whereas sulfur was related to more respiratory deaths. County-level smoking and alcohol were associated with larger estimated PM2.5 effects.ConclusionsOur study showed an increased risk of mortality associated with PM2.5, which varied with seasons and species. The results suggest that mass alone might not be sufficient to evaluate the health effects of particles.
| S-EPMC4123030 | biostudies-literature
Project description:Specification of PM2.5 spatial and temporal characteristics is important for understanding PM2.5 adverse effects and policymaking. We applied network analysis to studying the dataset MIX, which contains PM2.5 emissions recorded from 2168 monitoring stations in China in 2008 and 2010. The results showed that for PM2.5 emissions from industrial sector 8 clusters were found in 2008 but they merged together into a huge cluster in 2010, suggesting that industrial sector underwent an integrating process. For PM2.5 emissions from electricity generation sector, strong locality of clusters was revealed, implying that each region had its own electricity generation system. For PM2.5 emissions from residential sector, the same pattern of 10 clusters was uncovered in both years, implicating the household energy consumption unchanged from 2008 to 2010. For PM2.5 emissions from transportation sector, the same pattern of 5 clusters with many connections in-between was unraveled, indicating the high-speed development of transportation nationalwidely. Except for the known elements, mercury (Hg) surfaced as an element for particle nucleation. To our knowledge, this is the first network study in this field.
| S-EPMC5016853 | biostudies-other
Project description:OBJECTIVE:Higher traffic-related air pollution has been associated with higher body mass index (BMI) among children. However, few studies have assessed the associations among adults. METHODS:Participants (N?=?2,372) from the Framingham Offspring and Third Generation cohorts who underwent multidetector-computed tomography scans (2002-2005) were included. Residential-based proximity to the nearest major roadway and 1-year average levels of fine particulate matter (PM2.5 ) air pollution were estimated. BMI was measured at Offspring examination 7 (1998-2001) and Third Generation examination 1 (2002-2005); subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) were measured using multidetector-computed tomography. Linear regression models were used for continuous BMI, SAT, and VAT and logistic models for the binary indicator of obesity (BMI ?30 kg/m2 ), adjusting for demographic variables, individual- and area-level measures of socioeconomic position, and clinical and lifestyle factors. RESULTS:Participants who lived 60 m from a major roadway had 0.37 kg/m2 higher BMI (95% CI: 0.10 to 0.65 kg/m2 ), 78.4 cm3 higher SAT (95% CI: 4.5 to 152.3 cm3 ), and 41.8 cm3 higher VAT (95% CI: -4.7 to 88.2 cm3 ) than those who lived 440 m away. CONCLUSIONS:Living closer to a major roadway was associated with higher overall and abdominal adiposity.
| S-EPMC5125859 | biostudies-literature
Project description:We examined associations between ambient air pollution and hepatic steatosis among 2,513 participants from the Framingham (Massachusetts) Offspring Study and Third Generation Cohort who underwent a computed tomography scan (2002-2005), after excluding men who reported >21 drinks/week and women who reported >14 drinks/week. We calculated each participant's residential-based distance to a major roadway and used a spatiotemporal model to estimate the annual mean concentrations of fine particulate matter. Liver attenuation was measured by computed tomography, and liver-to-phantom ratio (LPR) was calculated. Lower values of LPR represent more liver fat. We estimated differences in continuous LPR using linear regression models and prevalence ratios for presence of hepatic steatosis (LPR ? 0.33) using generalized linear models, adjusting for demographics, individual and area-level measures of socioeconomic position, and clinical and lifestyle factors. Participants who lived 58 m (25th percentile) from major roadways had lower LPR (? = -0.003, 95% confidence interval: -0.006, -0.001) and higher prevalence of hepatic steatosis (prevalence ratio = 1.16, 95% confidence interval: 1.05, 1.28) than those who lived 416 m (75th percentile) away. The 2003 annual average fine particulate matter concentration was not associated with liver-fat measurements. Our findings suggest that living closer to major roadways was associated with more liver fat.
| S-EPMC5860476 | biostudies-literature