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Perfluoroalkyl acids (PFAAs) in the aquatic food web of a temperate urban lake in East China: Bioaccumulation, biomagnification, and probabilistic human health risk
2022
Chu, Kejian | Lü, Ying | Hua, Zulin | Liu, Yuanyuan | Ma, Yixin | Gu, Li | Gao, Chang | Yu, Liang | Wang, Yifan
The bioaccumulation and biomagnification of perfluoroalkyl acids (PFAAs) in temperate urban lacustrine ecosystems is poorly understood. We investigated the occurrence and trophic transfer of and probabilistic health risk from 15 PFAAs in the food web of Luoma Lake, a temperate urban lake in East China. The target PFAAs were widely distributed in the water (∑PFAA: 77.09 ± 9.07 ng/L), suspended particulate matter (SPM) (∑PFAA: 284.07 ± 118.05 ng/g dw), and sediment samples (∑PFAA: 67.77 ± 17.96 ng/g dw) and occurred in all biotic samples (∑PFAA: 443.27 ± 124.89 ng/g dw for aquatic plants; 294.99 ± 90.82 for aquatic animals). PFBA was predominant in water and SPM, with 40.11% and 21.35% of the total PFAAs, respectively, while PFOS was the most abundant in sediments (14.11% of the total PFAAs) and organisms (14.33% of the total PFAAs). Sediment exposure may be the major route of biological uptake of PFAAs. The PFAA accumulation capacity was the highest in submerged plants, followed by emergent plants > bivalves > crustaceans > fish > floating plants. Long-chain PFAAs were biomagnified, and short-chain PFAAs were biodiluted across the entire lacustrine food web. PFOS exhibited the greatest bioaccumulation and biomagnification potential among the target PFAAs. However, biomagnification of short-chain PFAAs was also observed within the low trophic-level part of the food web. Human health risk assessment indicated that perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA) posed health risks to all age groups, while the other PFAAs were unlikely to cause immediate harm to consumers in the region. This study fills a gap in the knowledge of the transfer of PFAAs in the food webs of temperate urban lakes.
Show more [+] Less [-]Elemental composition of fine and coarse particles across the greater Los Angeles area: Spatial variation and contributing sources
2022
Oroumiyeh, Farzan | Jerrett, Michael | Del Rosario, Irish | Lipsitt, Jonah | Liu, Jonathan | Paulson, Suzanne E. | Ritz, Beate | Schauer, James J. | Shafer, Martin M. | Shen, Jiaqi | Weichenthal, Scott | Banerjee, Sudipto | Zhu, Yifang
The inorganic components of particulate matter (PM), especially transition metals, have been shown to contribute to PM toxicity. In this study, the spatial distribution of PM elements and their potential sources in the Greater Los Angeles area were studied. The mass concentration and detailed elemental composition of fine (PM₂.₅) and coarse (PM₂.₅₋₁₀) particles were assessed at 46 locations, including urban traffic, urban community, urban background, and desert locations. Crustal enrichment factors (EFs), roadside enrichments (REs), and bivariate correlation analysis revealed that Ba, Cr, Cu, Mo, Pd, Sb, Zn, and Zr were associated with traffic emissions in both PM₂.₅ and PM₂.₅₋₁₀, while Fe, Li, Mn, and Ti were affected by traffic emissions mostly in PM₂.₅. The concentrations of Ba, Cu, Mo, Sb, Zr (brake wear tracers), Pd (tailpipe tracer), and Zn (associated with tire wear) were higher at urban traffic sites than urban background locations by factors of 2.6–4.6. Both PM₂.₅ and PM₂.₅₋₁₀ elements showed large spatial variations, indicating the presence of diverse emission sources across sampling locations. Principal component analysis extracted four source factors that explained 88% of the variance in the PM₂.₅ elemental concentrations, and three sources that explained 86% of the variance in the PM₂.₅₋₁₀ elemental concentrations. Based on multiple linear regression analysis, the contribution of traffic emissions (27%) to PM₂.₅ was found to be higher than mineral dust (23%), marine aerosol (18%), and industrial emissions (8%). On the other hand, mineral dust was the dominant source of PM₂.₅₋₁₀ with 45% contribution, followed by marine aerosol (22%), and traffic emissions (19%). This study provides novel insight into the spatial variation of traffic-related elements in a large metropolitan area.
Show more [+] Less [-]The relationship between particulate matter and lung function of children: A systematic review and meta-analysis
2022
Zhang, Wenjing | Ma, Runmei | Wang, Yanwen | Jiang, Ning | Zhang, Yi | Li, Tiantian
There have been many studies on the relationship between fine particulate matter (PM₂.₅) and lung function. However, the impact of short-term or long-term PM₂.₅ exposures on lung function in children is still inconsistent globally, and the reasons for the inconsistency of the research results are not clear. Therefore, we searched the PubMed, Embase and Web of Science databases up to May 2022, and a total of 653 studies about PM₂.₅ exposures on children's lung function were identified. Random effects meta-analysis was used to estimate the combined effects of the 25 articles included. PM₂.₅ concentrations in short-term exposure studies mainly come from individual and site monitoring. And for every 10 μg/m³ increase, forced vital capacity (FVC), forced expiratory volume in the first second (FEV₁) and peak expiratory flow (PEF) decreased by 21.39 ml (95% CI: 13.87, 28.92), 25.66 ml (95% CI: 14.85, 36.47) and 1.76 L/min (95% CI: 1.04, 2.49), respectively. The effect of PM₂.₅ on lung function has a lag effect. For every 10 μg/m³ increase in the 1-day moving average PM₂.₅ concentration, FEV₁, FVC and PEF decreased by 14.81 ml, 15.40 ml and 1.18 L/min, respectively. PM₂.₅ concentrations in long-term exposure studies mainly obtained via ground monitoring stations. And for every 10 μg/m³ increase, FEV₁, FVC and PEF decreased by 61.00 ml (95% CI: 25.80, 96.21), 54.47 ml (95% CI: 7.29, 101.64) and 10.02 L/min (95% CI: 7.07, 12.98), respectively. The sex, body mass index (BMI), relative humidity (RH), temperature (Temp) and the average PM₂.₅ exposure level modify the relationship between short-term PM₂.₅ exposure and lung function. Our study provides further scientific evidence for the deleterious effects of PM₂.₅ exposures on children's lung function, suggesting that exposure to PM₂.₅ is detrimental to children's respiratory health. Appropriate protective measures should be taken to reduce the adverse impact of air pollution on children's health.
Show more [+] Less [-]Association of household air pollution with cellular and humoral immune responses among women in rural Bangladesh
2022
Raqib, Rubhana | Akhtar, Evana | Sultana, Tajnin | Ahmed, Shyfuddin | Chowdhury, Muhammad Ashique Haider | Shahriar, Mohammad Hasan | Kader, Shirmin Bintay | Eunus, Mahbbul | Haq, Md Ahsanul | Sarwar, Golam | Islam, Tariqul | Alam, Dewan Shamsul | Parvez, Faruque | Begum, Bilkis A. | Ahsan, Habibul | Yunus, Mohammed
Household air pollution (HAP) arising from combustion of biomass fuel (BMF) is a leading cause of morbidity and mortality in low-income countries. Air pollution may stimulate pro-inflammatory responses by activating diverse immune cells and cyto/chemokine expression, thereby contributing to diseases. We aimed to study cellular immune responses among women chronically exposed to HAP through use of BMF for domestic cooking. Among 200 healthy, non-smoking women in rural Bangladesh, we assessed exposure to HAP by measuring particulate matter 2.5 (PM₂.₅), black carbon (BC) and carbon monoxide (CO), through use of personal monitors RTI MicroPEM™ and Lascar CO logger respectively, for 48 h. Blood samples were collected following HAP exposure assessment and were analyzed for immunoprofiling by flow cytometry, plasma IgE by immunoassay analyzer and cyto/chemokine response from monocyte-derived-macrophages (MDM) and -dendritic cells (MDDC) by multiplex immunoassay. In multivariate linear regression model, a doubling of PM₂.₅ was associated with small increments in immature/early B cells (CD19⁺CD38⁺) and plasmablasts (CD19⁺CD38⁺CD27⁺). In contrast, a doubling of CO was associated with 1.20% reduction in CD19⁺ B lymphocytes (95% confidence interval (CI) = -2.36, −0.01). A doubling of PM₂.₅ and BC each was associated with 3.12% (95%CI = −5.85, −0.38) and 4.07% (95%CI = −7.96, −0.17) decrements in memory B cells (CD19⁺CD27⁺), respectively. Exposure to CO was associated with increased plasma IgE levels (beta(β) = 240.4, 95%CI = 3.06, 477.8). PM₂.₅ and CO exposure was associated with increased MDM production of CXCL10 (β = 12287, 95%CI = 1038, 23536) and CCL5 (β = 835.7, 95%CI = 95.5, 1576), respectively. Conversely, BC exposure was associated with reduction in MDDC-produced CCL5 (β = −3583, 95%CI = −6358, −807.8) and TNF-α (β = −15521, 95%CI = −28968, −2074). Our findings suggest that chronic HAP exposure through BMF use adversely affects proportions of B lymphocytes, particularly memory B cells, plasma IgE levels and functions of antigen presenting cells in rural women.
Show more [+] Less [-]Atmospheric particulate represents a source of C8–C12 perfluoroalkyl carboxylates and 10:2 fluorotelomer alcohol in tree bark
2021
Zhao, Nan | Zhao, Meirong | Liu, Weiping | Jin, Hangbiao
In this study, we analyzed 30 legacy and emerging poly- and perfluoroalkyl substances (PFASs) in paired atmospheric particulate and bark samples collected around a Chinese fluorochemical manufacturing park (FMP), with the aim to explore the sources of PFASs in tree bark. The results showed that PFASs in atmospheric particulate and tree bark samples were consistently dominated by perfluorooctanoate (mean 73 ng/g; 44 pg/m³), perfluorohexanoate (47 ng/g; 36 pg/m³), perfluorononanoate (9.1 ng/g; 8.8 pg/m³), and 10:2 fluorotelomer alcohol (10:2 FTOH; 5.6 ng/g; 12 pg/m³). Spatially, concentrations of C₈–C₁₂ perfluoroalkyl carboxylates (PFCAs) and 10:2 FTOH all showed a similar and exponentially decreased trend in both bark and atmospheric particulate samples with the increasing distance from the FMP. For the first time, we observed strongly significant (Spearman’s correlation coefficient = 0.53–0.79, p < 0.01) correlations between bark and atmospheric particulate concentrations for C₈–C₁₂ PFCAs and 10:2 FTOH over 1–2 orders of magnitude, suggesting that the continues trapping of atmospheric particulates resulted in the accumulation of these compounds in bark. Overall, this study provides the first evidence that atmospheric particulate is an obvious source of C₈–C₁₂ PFCAs and 10:2 FTOH in tree bark. This result may further contribute to the application of tree bark as an indicator of certain PFASs in atmospheric particulate.
Show more [+] Less [-]Assessing the oxidative potential of PAHs in ambient PM2.5 using the DTT consumption assay
2021
Kramer, Amber L. | Dorn, Shelby | Perez, Allison | Roper, Courtney | Titaley, Ivan A. | Cayton, Kaylee | Cook, Ronald P. | Cheong, Paul H-Y | Massey Simonich, Staci L.
The oxidative potential (OP) of atmospheric fine particulate matter (PM₂.₅) has been linked to organic content, which includes polycyclic aromatic hydrocarbons (PAHs). The OP of 135 individual PAHs (including six subclasses) was measured using the dithiolthreitol (DTT) consumption assay. The DTT assay results were used to compute the concentration of each PAH needed to consume 50% of the DTT concentration in the assay (DTT₅₀), and the reduction potential of the PAHs (ΔGᵣₓₙ). Computed reduction potential results were found to match literature reduction potential values (r² = 0.97), while DTT₅₀ results had no correlations with the computed ΔGᵣₓₙ values (r² < 0.1). The GINI equality index was used to assess the electron distribution across the surface of unreacted and reacted PAHs. GINI values correlated with ΔGᵣₓₙ in UPAH, HPAH, and OHPAH subclasses, as well as with all 135 PAHs in this study but did not correlate with DTT₅₀, indicating that electron dispersion is linked to thermodynamic reactions and structural differences in PAHs, but not linked to the OP of PAHs. Three ambient PM₂.₅ filters extracts were measured in the DTT assay, alongside mixtures of analytical standards prepared to match PAH concentrations in the filter extracts to test if the OP follows an additive model of toxicity. The additive prediction model did not accurately predict the DTT consumption in the assay for any of the prepared standard mixtures or ambient PM₂.₅ filter extracts, indicating a much more complex model of toxicity for the OP of PAHs in ambient PM₂.₅. This study combined computed molecular properties with toxicologically relevant assay results to probe the OP of anthropogenically driven portions of ambient PM₂.₅, and results in a better understanding of the complexity of ambient PM₂.₅ OP.
Show more [+] Less [-]Assessment of the ability of roadside vegetation to remove particulate matter from the urban air
2021
Kończak, B. | Cempa, M. | Pierzchała, Ł | Deska, M.
The development of urbanised areas together with the growing transport infrastructure and traffic volume are the main cause of air quality deterioration due to the increasing concentrations of particulate matter. Dust pollution is a threat to human health. It can cause the development of lung, larynx or circulatory system cancer. Due to the ability to accumulate dust particles on the leaf surface, the contribution of trees in the process of phytoremediation of air pollution has started to be appreciated. An analysis of the elemental composition of particulate matter (PM) stored on the leaves surface was also carried out, which showed high average concentration of: C > O > Si > Fe (above 8wt.%). It was also observed single particles with a high concentration of heavy metals: Ti, Mn, Ba, Zn, Cr, Pb, Sn, Ni and REE (rare earth elements). The major origin of PM are vehicular emissions, soil and re-suspended road dust. This paper presents also a comparison of selected tree, shrub and vine species differing in their ability to accumulate particulate matter. It was experimentally determined the average leaf surface of individual plant species and established the amount of particulate matter with aerodynamic diameter between 10 and 100 μm, 2.5 and 10 μm, and 0.2 and 2.5 μm deposited on the leaf surface and in waxes.Some species of vines (Parthenocissus quinquefolia), shrubs (Forsythia x intermediata) and coniferous trees, such as Betula pendula ‘Youngii’, Quercus rubra, Cratageus monogyna, Acer pseduoplatanus, Tilia cordata Mill. or Platanus orientalis turned out to be the most efficient in the process of phylloremediation.
Show more [+] Less [-]Long-term exposure to particulate matter and roadway proximity with age at natural menopause in the Nurses’ Health Study II Cohort
2021
Li, Huichu | Hart, Jaime E. | Mahalingaiah, Shruthi | Nethery, Rachel C. | Bertone-Johnson, Elizabeth | Laden, Francine
Evidence has shown associations between air pollution and traffic-related exposure with accelerated aging, but no study to date has linked the exposure with age at natural menopause, an important indicator of reproductive aging. In this study, we sought to examine the associations of residential exposure to ambient particulate matter (PM) and distance to major roadways with age at natural menopause in the Nurses’ Health Study II (NHS II), a large, prospective female cohort in US. A total of 105,996 premenopausal participants in NHS II were included at age 40 and followed through 2015. Time-varying residential exposures to PM₁₀, PM₂.₅₋₁₀, and PM₂.₅ and distance to roads was estimated. We calculated hazard ratios (HR) and 95% confidence intervals (CIs) for natural menopause using Cox proportional hazard models adjusting for potential confounders and predictors of age at menopause. We also examined effect modification by region, smoking, body mass, physical activity, menstrual cycle length, and population density. There were 64,340 reports of natural menopause throughout 1,059,229 person-years of follow-up. In fully adjusted models, a 10 μg/m³ increase in the cumulative average exposure to PM₁₀ (HR: 1.02, 95% CI: 1.00, 1.04), PM₂.₅₋₁₀ (HR: 1.03, 95% CI: 1.00, 1.05), and PM₂.₅ (HR: 1.03, 95% CI: 1.00, 1.06) and living within 50 m to a major road at age 40 (HR: 1.03, 95%CI: 1.00, 1.06) were associated with slightly earlier menopause. No statistically significant effect modification was found, although the associations of PM were slightly stronger for women who lived in the West and for never smokers. To conclude, we found exposure to ambient PM and traffic in midlife was associated with slightly earlier onset of natural menopause. Our results support previous evidence that exposure to air pollution and traffic may accelerate reproductive aging.
Show more [+] Less [-]HVAC filtration of particles and trace metals: Airborne measurements and the evaluation of quantitative filter forensics
2021
Mahdavi, Alireza | Dingle, Justin | Chan, Arthur W.H. | Siegel, Jeffrey A.
Filters installed in the heating, ventilation, and air-conditioning (HVAC) systems can serve as air-cleaning and sampling devices for indoor particles. The purpose of this article is to evaluate these dual roles. An occupied home with a central HVAC system equipped with a Minimum Efficiency Reporting Value (MERV, from ASHRAE Standard 52.2) 11 filter was monitored for six weeks. Weekly airborne gravimetric and real-time sampling was performed to measure the particle size distribution and the concentration of total suspended particles (TSP), PM₁₀, PM₂.₅, PM₁, and 12 trace metals. The weekly system runtimes were intentionally changed to provide a wide range of weekly filtration volumes. The quantitative filter forensics (QFF) concentrations of particulate matter (PM) and trace metals were calculated using the analysis of the dust collected on the HVAC filter, the filtration volume, and filter in-situ efficiency. The results indicated that filtration was not influential to remove PM and trace metals as the concentrations during the weeks with continuous HVAC operation were not consistently lower than those during the other weeks. This suggests the dominance of other particle and trace metal source and loss mechanisms weakens the influence of filtration in this home. The QFF evaluation results indicated that the concentration of TSP and over half of the tested trace metals (e.g., Pb, Cd, Ni, V, Sb, K, and Sr) could be estimated by QFF within a factor of two when compared to airborne sampling results. PM₁₀, PM₂.₅, and PM₁ concentrations were significantly underestimated by QFF potentially due to the limitations of size distribution analysis by a laser diffraction particle sizer (LDPS) for the detection of <1 μm particles. Overall, while QFF was promising for TSP and some trace metals, improvement in size distribution analysis could extend the application of QFF for airborne sampling.
Show more [+] Less [-]Simultaneous observation of atmospheric peroxyacetyl nitrate and ozone in the megacity of Shanghai, China: Regional transport and thermal decomposition
2021
Zhang, Gen | Jing, Shengao | Xu, Wanyun | Gao, Yaqin | Yan, Chao | Liang, Linlin | Huang, Cheng | Wang, Hongli
Atmospheric peroxyacetyl nitrate (PAN) and ozone (O₃) are two typical indicators for photochemical pollution that have adverse effects on the ecosystem and human health. Observation networks for these pollutants have been expanding in developed regions of China, such as North China Plain (NCP) and Pearl River Delta (PRD), but are sparse in Yangtze River Delta (YRD), meaning their concentration and influencing factors remain poorly understood. Here, we performed a one-year measurement of atmospheric PAN, O₃, particulate matter with aerodynamic diameter smaller than 2.5 μm (PM₂.₅), nitrogen oxides (NOₓ), carbon monoxide (CO), and meteorological parameters from December 2016 to November 2017 in Shanghai. Overall, high hourly maximum PAN and O₃ were found to be 7.0 and 185 ppbv in summer, 6.2 and 146 ppbv in autumn, 5.8 and 137 ppbv in spring, and 6.0 and 76.7 ppbv in winter, respectively. Continental air masses probably carried atmospheric pollutants to the sampling site, while frequent maritime winds brought in less polluted air masses. Furthermore, positive correlations (R: 0.72–0.85) between PAN and O₃ were found in summer, indicating a predominant role of photochemistry in their formation. Unlike in summer, weak or no correlations between PAN and O₃ were featured during the other seasons, especially in winter, due to their different loss pathways. Unexpectedly, positive correlations between PAN and PM₂.₅ were found in all seasons. During summer, moderate correlation could be attributed to the strong photochemistry acting as a common driver in the formation of secondary aerosols and PAN. During winter, high PM₂.₅ might promote PAN production through HONO production, hence resulting in a good positive correlation. Additionally, the loss of PAN by thermal decomposition (TPAN) only accounted for a small fraction (ca. 1%) of the total (PAN + TPAN) during a typical winter episode, while it significantly reached 14.4 ppbv (71.1% of the total) in summer.
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