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Can the Air Pollution Index be used to communicate the health risks of air pollution? 全文
2015
Li, Li | Lin, Guo-Zhen | Liu, Hua-Zhang | Guo, Yuming | Ou, Chun-Quan | Chen, Ping-Yan
The validity of using the Air Pollution Index (API) to assess health impacts of air pollution and potential modification by individual characteristics on air pollution effects remain uncertain. We applied distributed lag non-linear models (DLNMs) to assess associations of daily API, specific pollution indices for PM10, SO2, NO2 and the weighted combined API (APIw) with mortality during 2003–2011 in Guangzhou, China. An increase of 10 in API was associated with a 0.88% (95% confidence interval (CI): 0.50, 1.27%) increase of non-accidental mortality at lag 0–2 days. Harvesting effects appeared after 2 days’ exposure. The effect estimate of API over lag 0–15 days was statistically significant and similar with those of pollutant-specific indices and APIw. Stronger associations between API and mortality were observed in the elderly, females and residents with low educational attainment. In conclusion, the API can be used to communicate health risks of air pollution.
显示更多 [+] 显示较少 [-]Concentration and chiral signature of chlordane in soils and sediments of the Central Tibetan Plateau, China: Transformation in the surficial process 全文
2015
Yuan, Guo-Li | Wu, Ming-Zhe | Sun, Yong | Li, Jun | Han, Peng | Wang, Gen-Hou
The fraction of trans-chlordane (TC) in chlordane was used to indicate racemic degradation while the enantiomer fractions (EFs) indicated enantioselective depletion. In 44 soils of the Central Tibetan Plateau, the fractions of TC ranged from 0.368 to 0.411. The EFs ranged from 0.174 to 0.696 for TC and from 0.483 to 0.672 for cis-chlordane (CC). (−) enantiomer excess (ee) was found to be 80.0% in the soils for TC and (+) ee was 86.5% for CC. The fraction of TC changed with the clay content while the EFs changed with the soil organic carbon. Meanwhile, the fractions of TC and the EFs were determined for the surficial sediments in Yamzhog Yumco Lake, which were compared with those in the soils at its catchment area. The composition and chiral signature of chlordane did not vary between soils and sediments. Our results will help to elucidate the transformation of chlordane in soils and in surficial transport.
显示更多 [+] 显示较少 [-]City as a major source area of fine particulate (PM2.5) in China 全文
2015
Han, Lijian | Zhou, Weiqi | Li, Weifeng
The PM2.5 concentration in 31% of China's territorial areas was less than 10 μg/m3, and in 26% of China's territorial areas was higher than 35 μg/m3. High concentrations of PM2.5 were found in the East China Plain, Sichuan province, and the Taklimakan desert. East China Plain was also found with strong significant positive trends. 73% of artificial surface (L01) was found with significant positive trends, but only 2% with significant negative trends. 76% of cropland (L02) was observed with significant positive trends, but only 2% with significant negative trends. The mean significant trends of PM2.5 concentration were 1.81 μg/m3·year for L01 and 1.71 μg/m3·year for L02, higher than that for the rest land covers. The PM2.5 pollution brought potential health risk to susceptible population: only 1% of thm lives at a safe level (<10 μg/m3), but 69% of them were exposed to heavy PM2.5 pollution (>35 μg/m3).
显示更多 [+] 显示较少 [-]Urban phenological studies – Past, present, future 全文
2015
Jochner, Susanne | Menzel, Annette
Phenology is believed to be a suitable bio-indicator to track climate change. Based on the strong statistical association between phenology and temperature phenological observations provide an inexpensive means for the temporal and spatial analysis of the urban heat island. However, other environmental factors might also weaken this relationship. In addition, the investigation of urban phenology allows an estimation of future phenology from current information since cities with their amplified temperatures may serve as a proxy for future conditions. Nevertheless, the design of spatial compared to long-term studies might be influenced by different factors which should be taken into consideration when interpreting results from a specific study. In general, plants located in urban areas tend to flush and bloom earlier than in the countryside. What are the consequences of these urban–rural differences? This review will document existing findings on urban phenology and will highlight areas in which further research is needed.
显示更多 [+] 显示较少 [-]Exposure to hazardous air pollutants and the risk of amyotrophic lateral sclerosis 全文
2015
Malek, Angela M. | Barchowsky, Aaron | Bowser, Robert | Heiman-Patterson, Terry | Lacomis, David | Rana, Sandeep | Ada Youk, | Talbott, Evelyn O.
Background: Amyotrophic lateral sclerosis (ALS) is a serious and rapidly fatal neurodegenerative disorder with an annual incidence of 1–2.6/100,000 persons. Few known risk factors exist although gene–environment interaction is suspected. We investigated the relationship between suspected neurotoxicant hazardous air pollutants (HAPs) exposure and ALS. Methods: A case–control study involving sporadic ALS cases (n = 51) and matched controls (n = 51) was conducted from 2008 to 2011. Geocoded residential addresses were linked to U.S. EPA NATA data (1999, 2002, and 2005) by census tract. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression. Results: Residential exposure to aromatic solvents significantly elevated the risk of ALS among cases compared to controls in 2002 (OR = 5.03, 95% CI: 1.29, 19.53) and 1999 (OR = 4.27, 95% CI: 1.09, 16.79) following adjustment for education, smoking, and other exposure groups. Metals, pesticides, and other HAPs were not associated with ALS. Conclusions: A potential relationship is suggested between residential ambient air aromatic solvent exposure and risk of ALS in this study.
显示更多 [+] 显示较少 [-]Atrazine triggers developmental abnormality of ovary and oviduct in quails (Coturnix Coturnix coturnix) via disruption of hypothalamo-pituitary-ovarian axis 全文
2015
Qin, Lei | Du, Zheng-Hai | Zhu, Shi-Yong | Li, Xue-Nan | Li, Nan | Guo, Jing-Ao | Li, Jin-Long | Zhang, Ying
There has been a gradual increase in production and consumption of atrazine (ATR) in agriculture to meet the population rising demands. Female reproduction is necessary for growth and maintenance of population. However, ATR impact on females and particularly ovarian developmental toxicity is less clear. The aim of this study was to define the pathways by which ATR exerted toxic effects on ovarian development of ovary and hypothalamo-pituitary-ovarian (HPO) axis. Female quails were dosed by oral gavage from sexual immaturity to maturity with 0, 50, 250 and 500 mg ATR/kg/d for 45 days. ATR had no effect on mortality but depressed feed intake and growth and influenced the biochemical parameters. Notably, the arrested development of ovaries and oviducts were observed in ATR-exposed quails. The circulating concentrations of E2, P, LH and PRL were unregulated and FSH and T was downregulated in ATR-treated quails. The mRNA expression of GnRH in hypothalamo and LH in pituitary and FSH in ovary was downregulated significantly by ATR exposure and FSH and PRL in pituitary were upregulated. ATR exposure upregulated the level of P450scc, P450arom, 3β-HSD and 17β-HSD in ovary and downregulated ERβ expression in female quails. However, ATR did not change ERα expression in ovary. This study provides new insights regarding female productive toxicology of ATR exposure. Ovary and oviduct in sexually maturing females were target organs of ATR-induced developmental toxicity. We propose that ATR-induced developmental abnormality of ovary and oviduct is associated with disruption of gonadal hormone balance and HPO axis in female quails.
显示更多 [+] 显示较少 [-]Polycyclic aromatic hydrocarbons in soils of the central Tibetan Plateau, China: Distribution, sources, transport and contribution in global cycling 全文
2015
Yuan, Guo-Li | Wu, Li-Juan | Sun, Yong | Li, Jun | Li, Jing-Chao | Wang, Gen-Hou
Forty-four soil samples were collected across the central Tibetan Plateau (CTP) at altitudes between 3711 m and 5352 m, and their polycyclic aromatic hydrocarbons (PAHs) contents were measured to be from 0.43 to 26.66 ng/g. The main sources of PAHs were identified for each of four sub-areas, and their concentrations in soils were determined to be mainly influenced by local sources. Along a 600 km sampling trajectory from Lhasa, which served as the biggest local source, the concentrations of PAHs decreased logarithmically with increasing distances from the source. Meanwhile, the fractional proportions of PAHs were observed to change logarithmically according to the transport distances. Conclusively, PAHs from local sources were transported within the CTP and dominated PAHs concentrations in the soils, but few of them were transported outside the CTP. In global cycling, the soils in the CTP mainly serve as background and a “sink” for PAHs.
显示更多 [+] 显示较少 [-]Size-dependent distribution and inhalation cancer risk of particle-bound polycyclic aromatic hydrocarbons at a typical e-waste recycling and an urban site 全文
2015
Luo, Pei | Bao, Lian-Jun | Li, Shao-Meng | Zeng, E. Y. (Eddy Y.)
Atmospheric particle size distribution of polycyclic aromatic hydrocarbons (PAHs) in a typical e-waste recycling zone and an urban site (Guangzhou) in southern China featured a unimodal peak in 0.56–1.8 μm for 4–6 ring PAHs but no obvious peak for 2–3 ring PAHs at both sites. The atmospheric deposition fluxes of PAHs were estimated at 5.4 ± 2.3 μg m−2 d−1 in the e-waste recycling zone and 3.1 ± 0.6 μg m−2 d−1 in Guangzhou. In addition, dry and wet deposition fluxes of PAHs were dominated by coarse (Dp > 1.8 μm) and fine particles (Dp < 1.8 μm), respectively. Fine particles predominated the deposition of PAHs in the lung. The results estimated by incremental inhalation cancer risk suggested that particle-bound PAHs posed serious threat to human health within the e-waste recycling zone and Guangzhou.
显示更多 [+] 显示较少 [-]Human disturbance affects the long-term spatial synchrony of freshwater invertebrate communities 全文
2015
Feio, M.J. | Dolédec, S. | Graça, M.A.S.
Taxonomic and trait composition of invertebrate communities were investigated for 4 reference and 5 disturbed Mediterranean stream sites over a 18 y period, to test the hypotheses that: 1) human disturbance reduces the resilience of communities to extreme climatic events by affecting their functional structure; 2) and as a result, extreme climatic events could lead to asynchronous responses of communities from streams with similar environmental characteristics but differently affected by human disturbance. In reference sites, trait compositions changed differently (were less similar over time) in response to extreme events and variation was less synchronic than taxonomic compositions in the same sites. Oppositely, in disturbed sites there was a marked synchrony in trait composition indicating a functional homogenization in response to human pressures. This limitation in “functional diversity” may involve a lower ability to respond to climatic extreme events and also a reduced potential in ecosystem services.
显示更多 [+] 显示较少 [-]Growth overcompensation against O3 exposure in two Japanese oak species, Quercus mongolica var. crispula and Quercus serrata, grown under elevated CO2 全文
2015
Kitao, Mitsutoshi | Komatsu, Masabumi | Yazaki, Kenichi | Kitaoka, Satoshi | Tobita, Hiroyuki
To assess the effects of elevated concentrations of carbon dioxide (CO2) and ozone (O3) on the growth of two mid-successional oak species native to East Asia, Quercus mongolica var. crispula and Quercus serrata, we measured gas exchange and biomass allocation in seedlings (initially 1-year-old) grown under combinations of elevated CO2 (550 μmol mol−1) and O3 (twice-ambient) for two growing seasons in an open-field experiment in which root growth was not limited. Both the oak species showed a significant growth enhancement under the combination of elevated CO2 and O3 (indicated by total dry mass; over twice of ambient-grown plants, p < .05), which probably resulted from a preferable biomass partitioning into leaves induced by O3 and a predominant enhancement of photosynthesis under elevated CO2. Such an over-compensative response in the two Japanese oak species resulted in greater plant growth under the combination of elevated CO2 and O3 than elevated CO2 alone.
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