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Revealing ecological risks of priority endocrine disrupting chemicals in four marine protected areas in Hong Kong through an integrative approach Full text
2016
Xu, Elvis Genbo | Ho, Philip Wing-Lok | Tse, Zero | Ho, Shu-Leong | Leung, Kenneth Mei Yee
Marine Protected Areas (MPAs) in Hong Kong are situated in close proximity to urbanized areas, and inevitably influenced by wastewater discharges and antifouling biocides leached from vessels. Hence, marine organisms inhabiting these MPAs are probably at risk. Here an integrative approach was employed to comprehensively assess ecological risks of eight priority endocrine disrupting chemicals (EDCs) in four MPAs of Hong Kong. We quantified their concentrations in environmental and biota samples collected in different seasons during 2013–2014, while mussels (Septifer virgatus) and semi-permeable membrane devices were deployed to determine the extent of accumulation of the EDCs. Extracts from the environmental samples were subjected to the yeast estrogen screen and a novel human cell-based catechol-O-methyltransferase ELISA to evaluate their estrogenic activities. The results indicated ecological risks of EDCs in the Cape d'Aguilar Marine Reserve. This integrated approach can effectively evaluate ecological risks of EDCs through linking their concentrations to biological effects.
Show more [+] Less [-]Trophic transfer and effects of DDT in male hornyhead turbot (Pleuronichthys verticalis) from Palos Verdes Superfund site, CA (USA) and comparisons to field monitoring Full text
2016
Crago, Jordan | Xu, Elvis Genbo | Kupsco, Allison | Jia, Fang | Mehinto, Alvine C. | Lao, Wenjian | Maruya, Keith A. | Gan, Jay | Schlenk, Daniel
High concentrations of DDT and metabolites (ΣDDT) have been detected in sediment and the demersal flatfish hornyhead turbot (Pleuronichtys verticalis) collected from Palos Verdes (PV), California, USA, a site contaminated with over 100 metric tons of DDT throughout 1960s–70s. This study was conducted to assess the transfer of ΣDDT from PV-sediment into polychaetes (Neanthes arenaceodentata) and hornyhead turbot, and to investigate if the responses in turbots from two different laboratory exposures mimic those in turbots caught in PV (PV-turbot). Turbot fed PV-sediment-contaminated polychaete for 7 days had liver concentrations of ΣDDT similar to PV-turbot. After 28 days, ΣDDT also accumulated in livers of turbot gavaged with a ΣDDT mixture. In vitro cell bioassays indicated significant increases of 17β-estradiol equivalents (EEQ) in turbot bile extracts as compared to the control in the 7-day study. These responses corresponded to those measured in PV-fish. Glucocorticoid receptor (GR), anti-androgen receptor (anti-AR), estrogen receptor (ER) or aryl hydrocarbon receptor (AhR) activities were also observed in extracts of PV-sediment, and PV-sediment-exposed worm. Anti-AR, AhR and GR activities were significantly higher in PV-sediment than reference sediment (San Diego, SD). Higher transcripts of hepatic VTG, ERα and ERβ were found in PV-turbot than SD-turbot, but were unaltered in fish exposed to sediment-contaminated worms for the 7-day study. In contrast, liver extracts from the 28-day treatment of ΣDDT showed lower EEQ but similar hepatic VTG and ERβ transcripts relative to those of PV-turbot. These data indicated that trophic transfer of sediment-associated DDT in 7-day exposures corresponded to field measurements of DDT residues and in vitro ER bioactivities, but failed to mimic in vivo biological effects observed in field fish. In contrast, treatment with ΣDDT alone for 28 days mimicked in vivo biological effects of DDTs in PV fish, but did not correspond to liver concentrations or in vitro bioactivities.
Show more [+] Less [-]Selenium exposure results in reduced reproduction in an invasive ant species and altered competitive behavior for a native ant species Full text
2016
De La Riva, Deborah G. | Trumble, John T.
Competitive ability and numerical dominance are important factors contributing to the ability of invasive ant species to establish and expand their ranges in new habitats. However, few studies have investigated the impact of environmental contamination on competitive behavior in ants as a potential factor influencing dynamics between invasive and native ant species. Here we investigated the widespread contaminant selenium to investigate its potential influence on invasion by the exotic Argentine ant, Linepithema humile, through effects on reproduction and competitive behavior. For the fecundity experiment, treatments were provided to Argentine ant colonies via to sugar water solutions containing one of three concentrations of selenium (0, 5 and 10 μg Se mL−1) that fall within the range found in soil and plants growing in contaminated areas. Competition experiments included both the Argentine ant and the native Dorymyrmex bicolor to determine the impact of selenium exposure (0 or 15 μg Se mL−1) on exploitation- and interference-competition between ant species. The results of the fecundity experiment revealed that selenium negatively impacted queen survival and brood production of Argentine ants. Viability of the developing brood was also affected in that offspring reached adulthood only in colonies that were not given selenium, whereas those in treated colonies died in their larval stages. Selenium exposure did not alter direct competitive behaviors for either species, but selenium exposure contributed to an increased bait discovery time for D. bicolor. Our results suggest that environmental toxins may not only pose problems for native ant species, but may also serve as a potential obstacle for establishment among exotic species.
Show more [+] Less [-]Cadmium-induced immune abnormality is a key pathogenic event in human and rat models of preeclampsia Full text
2016
Zhang, Qiong | Huang, Yinping | Zhang, Keke | Huang, Yanjun | Yan, Yan | Wang, Fan | Wu, Jie | Wang, Xiao | Xu, Zhangye | Chen, Yongtao | Cheng, Xue | Li, Yong | Jiao, Jinyu | Ye, Duyun
With increased industrial development, cadmium is an increasingly important environmental pollutant. Studies have identified various adverse effects of cadmium on human beings. However, the relationships between cadmium pollution and the pathogenesis of preeclampsia remain elusive. The objective of this study is to explore the effects of cadmium on immune system among preeclamptic patients and rats. The results showed that the cadmium levels in the peripheral blood of preeclamptic patients were significantly higher than those observed in normal pregnancy. Based on it, a novel rat model of preeclampsia was established by the intraperitoneal administration of cadmium chloride (CdCl2) (0.125 mg of Cd/kg body weight) on gestational days 9–14. Key features of preeclampsia, including hypertension, proteinuria, placental abnormalities and small foetal size, appeared in pregnant rats after the administration of low-dose of CdCl2. Cadmium increased immunoglobulin production, mainly angiotensin II type 1-receptor-agonistic autoantibodies (AT1-AA), by increasing the expression of activation-induced cytosine deaminase (AID) in B cells. AID is critical for the maturation of antibody and autoantibody responses. In addition, angiotensin II type 1-receptor-agonistic autoantibody, which emerged recently as a potential pathogenic contributor to PE, was responsible for the deposition of complement component 5 (C5) in kidneys of pregnant rats via angiotensin II type 1 receptor (AT1R) activation. C5a is a fragment of C5 that is released during C5 activation. Selectively interfering with C5a signalling by a complement C5a receptor-specific antagonist significantly attenuated hypertension and proteinuria in Cd-injected pregnant rats. Our results suggest that cadmium induces immune abnormalities that may be a key pathogenic contributor to preeclampsia and provide new insights into treatment strategies of preeclampsia.
Show more [+] Less [-]Dandelion Taraxacum linearisquameum does not reflect soil metal content in urban localities Full text
2016
Kováčik, Jozef | Dudáš, Matej | Hedbavny, Josef | Mártonfi, Pavol
Accumulation of selected heavy metals (Cd, Pb, Ni, Cr, Fe, and Zn) and phenolic metabolites (total soluble phenols, cichoric and caftaric acid) in dandelion organs (leaves, roots, inflorescences/anthodia) collected from six localities within the industrial town Košice (eastern Slovakia) were studied. Localities from the vicinity of a steel factory (Cd, Fe) and heavy traffic (Pb, Ni, Cr, Zn) contained the highest amount of individual metals in the soil but a significant correlation between soil and organ metal content was found only for Cr in the leaves (r2 = 0.7679). The amount of Cd and partially Pb differed among localities in all organs and especially in the leaves and anthodia, indicating probably the impact of atmospheric pollution. The bioaccumulation factor was <1 for almost all metals, suggesting that given dandelion species is not metal accumulator. Translocation factor did not reach values close to or over 1 only for Cd, indicating a root-to-shoot movement of Pb, Ni and Zn though the impact of air pollution on leaves cannot be excluded. A strong correlation between leaf Cd and leaf total phenols, cichoric and caftaric acids was observed (r2 = 0.7926, 0.8682 and 0.8830, respectively), indicating that phenolic metabolites act in the protection of dandelion against Cd excess. Overall, our data indicate low pollution of urban soil by Cd (5.53–113.8 ng g−1) and partially by Cr and the suitability of above-ground organs of dandelion species for the monitoring of air pollution mainly by Cd.
Show more [+] Less [-]Increase in dust storm related PM10 concentrations: A time series analysis of 2001–2015 Full text
2016
Krasnov, Helena | Katra, Itzhak | Friger, Michael
Over the last decades, changes in dust storms characteristics have been observed in different parts of the world. The changing frequency of dust storms in the southeastern Mediterranean has led to growing concern regarding atmospheric PM10 levels. A classic time series additive model was used in order to describe and evaluate the changes in PM10 concentrations during dust storm days in different cities in Israel, which is located at the margins of the global dust belt. The analysis revealed variations in the number of dust events and PM10 concentrations during 2001–2015. A significant increase in PM10 concentrations was identified since 2009 in the arid city of Beer Sheva, southern Israel. Average PM10 concentrations during dust days before 2009 were 406, 312, and 364 μg m−3 (median 337, 269,302) for Beer Sheva, Rehovot (central Israel) and Modi'in (eastern Israel), respectively. After 2009 the average concentrations in these cities during dust storms were 536, 466, and 428 μg m−3 (median 382, 335, 338), respectively. Regression analysis revealed associations between PM10 variations and seasonality, wind speed, as well as relative humidity. The trends and periodicity are stronger in the southern part of Israel, where higher PM10 concentrations are found. Since 2009 dust events became more extreme with much higher daily and hourly levels. The findings demonstrate that in the arid area variations of dust storms can be quantified easier through PM10 levels over a relatively short time scale of several years.
Show more [+] Less [-]Data concurrency is required for estimating urban heat island intensity Full text
2016
Zhao, Shuqing | Zhou, Decheng | Liu, Shuguang
Urban heat island (UHI) can generate profound impacts on socioeconomics, human life, and the environment. Most previous studies have estimated UHI intensity using outdated urban extent maps to define urban and its surrounding areas, and the impacts of urban boundary expansion have never been quantified. Here, we assess the possible biases in UHI intensity estimates induced by outdated urban boundary maps using MODIS Land surface temperature (LST) data from 2009 to 2011 for China's 32 major cities, in combination with the urban boundaries generated from urban extent maps of the years 2000, 2005 and 2010. Our results suggest that it is critical to use concurrent urban extent and LST maps to estimate UHI at the city and national levels. Specific definition of UHI matters for the direction and magnitude of potential biases in estimating UHI intensity using outdated urban extent maps.
Show more [+] Less [-]Cross-sectional association between exposure to particulate matter and inflammatory markers in the Japanese general population: NIPPON DATA2010 Full text
2016
Michikawa, Takehiro | Okamura, Tomonori | Nitta, Hiroshi | Nishiwaki, Yuji | Takebayashi, Toru | Ueda, Kayo | Kadota, Aya | Fujiyoshi, Akira | Ohkubo, Takayoshi | Ueshima, Hirotsugu | Okayama, Akira | Miura, Katsuyuki
A suggestive mechanism behind the association between particulate matter and cardiovascular disease is inflammatory response. Earlier population-based studies investigating the association between particulate matter and inflammatory biological markers, in particular C-reactive protein (CRP), showed inconsistent results. In addition, evidence from the Asian population, in which CRP levels are typically lower than those observed in Western populations, was sparse. We examined the cross-sectional association between short- and long-term exposure to particulate matter and inflammatory markers, including high-sensitivity CRP (hs-CRP) and white blood cell (WBC) count, in a representative population of Japanese community dwellers (NIPPON DATA2010). We analysed data from 2360 participants (1002 men and 1358 women), aged 20 years or older, who resided in 300 randomly selected districts (222 public health centre areas) throughout Japan. We used background concentrations of suspended particulate matter (SPM, defined as particles with a 100% cut-off level at 10 μm aerodynamic diameter) and co-pollutants within the public health centre area. A logistic regression model was applied to estimate odds ratios (ORs) of elevated hs-CRP (> 0.3 mg/dl) or WBC (> 9000/μl). Since smoking is an important confounding factor, we firstly included this in the models, and additionally conducted the analyses after excluding current smokers. The one-month average concentration of SPM was positively associated with hs-CRP (OR per 10 μg/m3 increase in SPM = 1.42, 95% confidence interval = 1.00–2.04), and high exposure to SPM on the day of blood draw was associated with increased WBC count, after excluding current smokers (OR = 1.13, 1.01–1.28). Similar association patterns were observed for ozone. In conclusion, exposure to particulate matter was associated with inflammatory markers in the general Japanese population. Systemic inflammation may play a role in the link between particulate matter and cardiovascular disease.
Show more [+] Less [-]The way forward for risk assessment of nanomaterials in solid media Full text
2016
Scott-Fordsmand, Janeck J. | Peijnenburg, Willie | Amorim, Mónica J.B. | Landsiedel, Robert | Oorts, Koen
There is an urgent need for sufficient knowledge to allow reliable assessment of the risks associated with engineered nanomaterials (ENPs). Significant advances in basic understanding of nano safety have been made, but there is still no clear systematic basis for risk-related research, and major uncertainties remain in the absence of uniform procedures. The following papers provide the guidance on how to proceed within the area of fate and hazard assessment, and how this links into grouping, testing and risk assessment of nanomaterials. This guidance is coupled with an industrial view on the most important research areas for nanomaterials.
Show more [+] Less [-]PM2.5 source attribution for Seoul in May from 2009 to 2013 using GEOS-Chem and its adjoint model Full text
2016
Lee, Hyung-Min | Park, Rokjin J. | Henze, Daven K. | Lee, Seungun | Shim, Changsub | Shin, Hye-Jung | Moon, Kwang-Joo | Woo, Jung-Hun
Enforcement of an air quality standard for PM2.5 in the Seoul metropolitan area (SMA) was enacted in 2015. From May to June of 2016, an international airborne and surface measurement campaign took place to investigate air pollution mechanisms in the SMA. The total and speciated PM2.5 concentrations since 2008 have been measured at an intensive monitoring site for the SMA operated by the National Institute of Environmental Research (NIER). To gain insight on the trends and sources of PM2.5 in the SMA in May, we analyze PM2.5 concentrations from 2009 to 2013 using the measurements and simulations from a 3-dimensional global chemical transport model, GEOS-Chem and its adjoint. The model is updated here with the latest regional emission inventory and diurnally varying NH3 emissions. Monthly average PM2.5 concentration measured by β-ray attenuation ranges from 28 (2010) to 45 (2013) μg/m3, decreased from 2009 to 2010, and then continuously increased until 2013. The model shows good agreement with the measurements for the daily average PM2.5 concentrations (R ≥ 0.5), and reproduces 10 out of 17 measured episodes exceeding the daily air quality standard (50 μg/m3). Using the GEOS-Chem adjoint model, we find that anthropogenic emissions from the Shandong region have the largest modeled influence on PM2.5 in Seoul in May. Average contributions to the high PM2.5 episodes simulated by the model are 39% from the Shandong region, 16% from the Shanghai region, 14% from the Beijing region, and 15% from South Korea. Anthropogenic SO2 emissions from South Korea are negligible with 90% of the total contribution originating from China. Findings from this study may guide interpretation of observations obtained in the KORUS-AQ measurement campaign.
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