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Characterization of phthalates exposure and risk for cosmetics and perfume sales clerks Полный текст
2018
Huang, Po-Chin | Liao, Kai-Wei | Chang, Jung-Wei | Chan, Shiou-Hui | Lee, Ching-Chang
High levels of phthalates in name-brand cosmetics products have raised concerns about phthalate exposure and the associated risk for cosmetics sales clerks. We assessed the exposure and risk of phthalates in 23 cosmetics, 4 perfume, and 9 clothing department store sales clerks. We collected 108 urine samples pre- and post-shift and analyzed for phthalate monoesters through liquid chromatography–electrospray ionization–tandem mass spectrometry. Phthalates in 32 air samples were collected and analyzed through gas chromatography–mass spectrometry. Demographic characteristics and information on the exposure scenarios were obtained through questionnaires. Principal component analysis, cluster and risk analysis were applied to identify the exposure profile and risk of phthalate.Median post-shift levels of urinary mono-2-ethylhexyl phthalate (MEHP) and monomethyl phthalate (MMP) were significantly higher than the corresponding pre-shift levels in cosmetics group (53.3 vs. 30.9 μg/g-c for MEHP; 34.4 vs. 22.5 μg/g-c for MMP; both P < 0.05) and the post-shift levels of urinary MMP was significantly higher than the corresponding pre-shift levels in perfume group (26.6 vs. 14.9 μg/g-c, P < 0.05). Median levels of air diethyl phthalate (DEP) in cosmetics (1.77 μg/m³) and perfume (1.75 μg/m³) groups and di-(2-ethylhexyl) phthalate (DEHP) in perfume group (6.98 μg/m³) were higher than those in clothing group (DEP: 0.89; DEHP: 2.16 μg/m³). Over half of cosmetic (70%) and perfume sale clerks had exceeded cumulative risk of phthalate exposure for anti-androgenic effect. We concluded that cosmetic and perfume workers had increased risks of reproductive or hepatic effects for DBP and DEHP exposure. We suggest that not only inhalation but dermal exposure is important route of phthalate exposure for cosmetics and perfume workers.
Показать больше [+] Меньше [-]Ozone risk assessment is affected by nutrient availability: Evidence from a simulation experiment under free air controlled exposure (FACE) Полный текст
2018
Zhang, Lu | Hoshika, Yasutomo | Carrari, Elisa | Badea, Ovidiu | Paoletti, Elena
Assessing ozone (O3) risk to vegetation is crucial for informing policy making. Soil nitrogen (N) and phosphorus (P) availability could change stomatal conductance which is the main driver of O3 uptake into a leaf. In addition, the availability of N and P could influence photosynthesis and growth. We thus postulated that the sensitivity of plants to O3 may be changed by the levels of N and P in the soil. In this study, a sensitive poplar clone (Oxford) was subject to two N levels (N0, 0 kg N ha−1; N80, 80 kg N ha−1), three P levels (P0, 0 kg P ha−1; P40, 40 kg P ha−1; P80, 80 kg P ha−1) and three levels of O3 exposure (ambient concentration, AA; 1.5 × AA; 2.0 × AA) for a whole growing season in an O3 free air controlled exposure (FACE) facility. Flux-based (POD0 to 6) and exposure-based (W126 and AOT40) dose-response relationships were fitted and critical levels (CLs) were estimated for a 5% decrease of total annual biomass. It was found that N and P availability modified the dose-response relationships of biomass responses to O3. Overall, the N supply decreased the O3 CLs i.e. increased the sensitivity of poplar to O3. Phosphorus alleviated the O3-caused biomass loss and increased the CL. However, such mitigation effects of P were found only in low N and not in high N conditions. In each nutritional treatment, similar performance was found between flux-based and exposure-based indices. However, the flux-based approach was superior, as compared to exposure indices, to explain the biomass reduction when all nutritional treatments were pooled together. The best O3 metric for risk assessments was POD4, with 4.6 mmol m−2 POD4 as a suitable CL for Oxford poplars grown under various soil N and P conditions.
Показать больше [+] Меньше [-]Predicting the effects of polychlorinated biphenyls on cetacean populations through impacts on immunity and calf survival Полный текст
2018
Hall, Ailsa J. | McConnell, Bernie J. | Schwacke, Lori H. | Ylitalo, Gina M. | Williams, Rob | Rowles, Teri K.
The potential impact of exposure to polychlorinated biphenyls (PCBs) on the health and survival of cetaceans continues to be an issue for conservation and management, yet few quantitative approaches for estimating population level effects have been developed. An individual based model (IBM) for assessing effects on both calf survival and immunity was developed and tested. Three case study species (bottlenose dolphin, humpback whale and killer whale) in four populations were taken as examples and the impact of varying levels of PCB uptake on achievable population growth was assessed. The unique aspect of the model is its ability to evaluate likely effects of immunosuppression in addition to calf survival, enabling consequences of PCB exposure on immune function on all age-classes to be explored. By incorporating quantitative tissue concentration-response functions from laboratory animal model species into an IBM framework, population trajectories were generated. Model outputs included estimated concentrations of PCBs in the blubber of females by age, which were then compared to published empirical data. Achievable population growth rates were more affected by the inclusion of effects of PCBs on immunity than on calf survival, but the magnitude depended on the virulence of any subsequent encounter with a pathogen and the proportion of the population exposed. Since the starting population parameters were from historic studies, which may already be impacted by PCBs, the results should be interpreted on a relative rather than an absolute basis. The framework will assist in providing quantitative risk assessments for populations of concern.
Показать больше [+] Меньше [-]Can in vitro assays account for interactions between inorganic co-contaminants observed during in vivo relative bioavailability assessment? Полный текст
2018
Ollson, Cameron J. | Smith, Euan | Juhasz, Albert L.
In vitro assays act as surrogate measurements of relative bioavailability (RBA) for inorganic contaminants. The values derived from these assays are routinely used to refine human health risk assessments (HHRA). Extensive in vitro research has been performed on three major inorganic contaminants; As, Cd and Pb. However, the majority of these studies have evaluated the contaminants individually, even in cases when they are found as co-contaminants. Recently, in vivo studies (animal model) have determined that when the three aforementioned contaminants are present in the same soil matrix, they have the ability to influence each other's individual bioavailability. Since in vitro assays are used to inform HHRA, this study investigated whether bioaccessibility methods including the Solubility/Bioavailability Research Consortium (SBRC) assay, and physiologically based extraction test (PBET), have the ability to detect interactions between As, Cd and Pb. Using a similar dosing methodology to recently published in vivo studies, spiked aged (12 years) soil was assessed by evaluating contaminant bioaccessibility individually, in addition to tertiary combinations. In two spiked aged soils (grey and brown chromosols), there was no influence on contaminant bioaccessibility when As, Cd and Pb we present as co-contaminants. However, in a red ferrosol, the presence of As and Pb significantly decreased (p < 0.05) the bioaccessibility of Cd when assessed using gastric and intestinal phases of the SBRC assay and the PBET. Conceivable, differences in key physico-chemical properties (TOC, Fe, Al, P) between the study soils influenced contaminant interactions and bioaccessibility outcomes. Although bioaccessibility methods may not account for interactions between elements as demonstrated in in vivo models, in vitro assessment provides a conservative prediction of contaminant RBA under co-contaminant scenarios.
Показать больше [+] Меньше [-]Combined impact of fishmeal and tetracycline on resistomes in mariculture sediment Полный текст
2018
Han, Ying | Wang, Jing | Zhao, Zelong | Chen, Jingwen | Lu, Hong | Liu, Guangfei
Mariculture sediment has been recognized as a major contributor of environmental antibiotic resistance genes (ARGs), which are challenging the treatment of infections worldwide. Both antibiotics and fishmeal are used in aquaculture, and each has the potential to facilitate ARG dissemination, however their combined impact on the sediment resistome and their relative contribution remain unclear. In this study, microcosms were exposed to varying concentrations of tetracycline with or without fishmeal (0.1% wt/wt) for 14 days. Sediment genomic DNA was analyzed using high throughput quantitative PCR and 16S rRNA gene amplicon sequencing to compare the contribution of fishmeal and tetracycline to antibiotic resistomes and bacterial communities in mariculture sediment. Sixty-seven ARGs were detected potentially correlating to resistance for several major antibiotics. Fishmeal, but not the dose of tetracycline, contributed to the significant increase of both ARG abundance and diversity in the sediment. Based on principle coordinate analysis and hierarchical clustering, ARGs were clustered into two groups depending on whether fishmeal was added. Aminoglycoside, macrolide–lincosamide–streptogramin b (MLSb) and tetracycline resistance genes were the most abundant when fishmeal was used, while a significant increase in mobile genetic element (MGE) abundance was also detected (P < 0.05). Meanwhile, bacterial community structures were detected with distinct patterns between the two groups (Adonis, P < 0.05). Using the Mantel test and partial least squares path modeling, we identified that sediment resistomes were significantly correlated with microbial community structures (P < 0.05) which were mainly driven by nutrients in fishmeal. Together our findings suggested that fishmeal plays a more important role than tetracycline in proliferation of ARGs in mariculture sediment. This study may provide new insights into the mitigation of ARG propagation in mariculture operations.
Показать больше [+] Меньше [-]Bioaugmentation of thiabendazole-contaminated soils from a wastewater disposal site: Factors driving the efficacy of this strategy and the diversity of the indigenous soil bacterial community Полный текст
2018
Papadopoulou, Evangelia S. | Genitsaris, Savvas | Omirou, Michalis | Perruchon, Chiara | Stamatopoulou, Anastasia | Ioannides, Ioannis | Karpouzas, Dimitrios G.
The application of the fungicide thiabendazole (TBZ) in fruit packaging plants (FPP) results in the production of effluents which are often disposed in adjacent field sites. These require remediation to prevent further environmental dispersal of TBZ. We assessed the bioaugmentation potential of a newly isolated TBZ-degrading bacterial consortium in a naturally contaminated soil (NCS) exhibiting a natural gradient of TBZ levels (12000, 400, 250 and 12 mg kg⁻¹). The effect of aging on bioaugmentation efficacy was comparatively tested in a soil with similar physicochemical properties and soil microbiota, which was artificially, contaminated with the same TBZ levels (ACS). The impact of bioaugmentation and TBZ on the bacterial diversity in the NCS was explored via amplicon sequencing. Bioaugmentation effectively removed TBZ from both soils at levels up to 400 mg kg⁻¹ but failed at the highest contamination level (12000 mg kg⁻¹). Dissipation of TBZ in bioaugmented samples showed a concentration-dependent pattern, while aging of TBZ had a slight effect on bioaugmentation efficiency. Bioaugmentation had no impact on the soil bacterial diversity, in contrast to TBZ contamination. Soils from the hotspots of TBZ contamination (12000 mg kg⁻¹) showed a drastically lower α-diversity driven by the dominance of β- and γ-proteobacteria at the expense of all other bacterial phyla, especially Actinobacteria. Overall, bioaugmentation with specialized microbial inocula could be an effective solution for the recovery of disposal sites contaminated with persistent chemicals like TBZ.
Показать больше [+] Меньше [-]Comparison of PM2.5 chemical composition and sources at a rural background site in Central Europe between 1993/1994/1995 and 2009/2010: Effect of legislative regulations and economic transformation on the air quality Полный текст
2018
Pokorná, Petra | Schwarz, Jaroslav | Krejci, Radovan | Swietlicki, Erik | Havránek, Vladimír | Ždímal, Vladimír
From December 1993 to January 1995 and from October 2009 to October 2010, a total of 320 and 365 daily samples of the PM2.5 were collected at a rural background site (National Atmospheric Observatory Košetice) in Central Europe. The PM2.5 samples were analyzed for 29 and 26 elements respectively by Particle-Induced X-ray Emission (PIXE) and water-soluble inorganic ions by Ion Chromatography (IC) in 2009/2010. The Positive Matrix Factorization (PMF) was applied to the chemical composition of PM2.5 to determine its sources. The decreasing trends of almost all elements concentrations, especially the metals regulated by the EU Directive (2004/107/EC) are evident. The annual median ratios indicate a decrease in concentrations of the PM2.5 elements. The slight increase of K concentrations and Spearman's rank correlation coefficient rs 0.09 K/Se points to a rise in residential wood combustion. The S concentrations are nearly comparable (higher mean in 2009/2010, while the annual median ratio is under 1). The five major source types in the mid-1990s were ascribed to brown coal combustion, oil combustion, sea salt and dust – long-range transport, re-suspended dust and black coal combustion. The industrial combustion of brown and/or black coal (rs 0.75 Se/As, rs 0.57 Ga/Ge and rs 0.20 As/Zn) and oil (rs 0.72 V/Ni) of the regional origin dominated. In the 1990s, the potential source regions were the border area of Czech Republic, German and Poland (brown coal), the Moravia-Silesia region at the Czech-Polish border (black coal), and Slovakia, Austria, Hungary, and the Balkans (oil). In 2009/2010, the apportioned sources were sulfate, residential heating, nitrate, industry, re-suspended dust, and sea salt and dust – long-range transport. The secondary sulfate from coal combustion and residential biomass burning (rs 0.96, K/K+) of local origin dominated.The declining trend of the elemental concentrations and change in the source pattern of the regional background PM2.5 in Central Europe between the mid-1990s and 2009/10 reflects the economic transformation and impact of stricter legislation in Central Europe.
Показать больше [+] Меньше [-]Ants and their nests as indicators for industrial heavy metal contamination Полный текст
2018
Skaldina, Oksana | Peräniemi, Sirpa | Sorvari, Jouni
Ants accumulate heavy metals and respond to pollution with modification in species composition, community structure, altered behaviour and immunity. However, the levels of heavy metals in ants’ nests and explicit individual-level responses towards heavy metals have not been revealed. We found that red wood ants Formica lugubris accumulate high and correlated values of such heavy metals as Al, Cd, Co, Cu, Fe, Ni, Pb and Zn both in ants and nest material near cobalt smelter in Finland. Relative differences in metal concentrations were higher in nests than in ants. The highest values were obtained for elements such as Co (36.6), Zn (14.9), Cd (9.7), Pb (8.5), Cu (7.4), Ni (6.4), As (4.7), Cr (2.9) and Fe (2.4) in nest material, and Co (32.7), Cd (6.3), Pb (6), Fe (2.8), Ni (2.9) and Zn (2.1) in ants. In industrial and reference areas, ants have no differences in size, but differed in dry and residual body mass. In polluted areas, F. lugubris had less melanised heads, but not thoraxes. The sensitivity of cuticular colouration in red wood ants subjected to heavy metal pollution might be related to metal-binding properties of melanins. The overall results are useful for the improvement of biomonitoring techniques using ants as indicators of industrial contamination and for further discovery of novel ecotoxicological biomarkers.
Показать больше [+] Меньше [-]Human health risk assessment for nanoparticle-contaminated aquifer systems Полный текст
2018
Tosco, Tiziana | Sethi, Rajandrea
Nanosized particles (NPs), such as TiO₂, Silver, graphene NPs, nanoscale zero-valent iron, carbon nanotubes, etc., are increasingly used in industrial processes, and releases at production plants and from landfills are likely scenarios for the next years. As a consequence, appropriate procedures and tools to quantify the risks for human health associated to these releases are needed.The tiered approach of the standard ASTM procedure (ASTM-E2081-00) is today the most applied for human health risk assessment at sites contaminated by chemical substances, but it cannot be directly applied to nanoparticles: NP transport along migration pathways follows mechanisms significantly different from those of chemicals; moreover, also toxicity indicators (namely, reference dose and slope factor) are NP-specific. In this work a risk assessment approach modified for NPs is proposed, with a specific application at Tier 2 to migration in groundwater. The standard ASTM equations are modified to include NP-specific transport mechanisms. NPs in natural environments are typically characterized by a heterogeneous set of NPs having different size, shape, coating, etc. (all properties having a significant impact on both mobility and toxicity). To take into account this heterogeneity, the proposed approach divides the NP population into classes, each having specific transport and toxicity properties, and simulates them as independent species. The approach is finally applied to a test case simulating the release of heterogeneous Silver NPs from a landfill. The results show that taking into account the size-dependent mobility of the particles provides a more accurate result compared to the direct application of the standard ASTM procedure. In particular, the latter tends to underestimate the overall toxic risk associated to the nP release.
Показать больше [+] Меньше [-]Estimating hourly PM1 concentrations from Himawari-8 aerosol optical depth in China Полный текст
2018
Zang, Julin | Mao, Feiyue | Guo, Jianping | Gong, Wei | Wang, Wei | Pan, Zengxin
Particulate matter with diameter less than 1 μm (PM1) has been found to be closely associated with air quality, climate changes, and even adverse human health. However, a large gap in our knowledge concerning the large-scale distribution and variability of PM1 remains, which is expected to be bridged with advanced remote-sensing techniques. In this study, a hybrid model called principal component analysis-general regression neural network (PCA-GRNN) is developed to estimate hourly PM1 concentrations from Himawari-8 aerosol optical depth in combination with coincident ground-based PM1 measurements in China. Results indicate that the hourly estimated PM1 concentrations from satellite agree well with the measured values at national scale, with R2 of 0.65, root-mean-square error (RMSE) of 22.0 μg/m3 and mean absolute error (MAE) of 13.8 μg/m3. On daily and monthly time scales, R2 increases to 0.70 and 0.81, respectively. Spatially, highly polluted regions of PM1 are largely located in the North China Plain and Northeast China, in accordance with the distribution of industrialisation and urbanisation. In terms of diurnal variability, PM1 concentration tends to peak in rush hours during the daytime. PM1 exhibits distinct seasonality with winter having the largest concentration (31.5±3.5 μg/m3), largely due to peak combustion emissions. We further attempt to estimate PM2.5 and PM10 with the proposed method and find that the accuracies of the proposed model for PM1 and PM2.5 estimation are significantly higher than that of PM10. Our findings suggest that geostationary data is one of the promising data to estimate fine particle concentration on large spatial scale.
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