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Arsenic accumulation in edible vegetables and health risk reduction by groundwater treatment using an adsorption process
2019
Spognardi, Sara | Bravo, Ilenia | Beni, Claudio | Menegoni, Patrizia | Pietrelli, Loris | Papetti, Patrizia
The heavy metals transfer from the soil, where they accumulate, to the edible parts of the plants, and then, their entrance in the food chain can represent a source of concern for human health. Among heavy metals, arsenic is one of the most widespread in the soil of Lazio (central region of Italy), where the phytoavailable geogenic arsenic enters the food chain, with a dangerous exposition of the local population. In the first part of this work, plants of radish (Raphanus sativus L.) and lettuce (Lactuca sativa L.) were grown in protected culture in the experimental farm of CREA-AA, where they were daily treated with different concentrations of sodium arsenate dibasic heptahydrate in order to investigate differences in their arsenic accumulation capacities. In order to confirm the results achieved, in the second part of this study, the arsenic concentration was determined in commercial products obtained from contaminated areas of Lazio, and the potential exposition risk for human health through consumption of these widely consumed vegetables was estimated. The highest arsenic concentrations were found in the samples of lettuce. To evaluate the potential health risk from consumption of L. sativa and R. sativus, the estimated daily intake (EDI) for adults, adolescents, and elderly was calculated, finding that HRI (health risk index) index value for arsenic was low (< 1) in the case of chronic consumptions for all samples of radishes, and for the lettuces grown in the area of Viterbo. On the contrary, the lettuces obtained from Tuscania and Tarquinia presented very high concentrations of arsenic and a worrying HRI value. In order to reduce the risk of As toxicity in the people through consumption of the vegetables, the irrigation water should contain less than 0.1 mg As L⁻¹. For this reason, the authors tested the application of red mud (RM) to remove As from groundwater before using it for the irrigation of radish and lettuce in greenhouse production.
显示更多 [+] 显示较少 [-]Partial ameliorative effect of Moringa leaf ethanolic extract on the reproductive toxicity and the expression of steroidogenic genes induced by subchronic cadmium in male rats
2019
Elblehi, Samar S. | El Euony, Omnia I. | El-Nahas, Abeer F.
The impact of Moringa oleifera leaf ethanol extract (MOLEE) was assessed on the expression of the steroidogenic genes (steroidogenic acute regulatory protein (StAR) and cytochrome P450c17 subfamily a (CYP17a) and luteinizing hormone receptor (LHR) gene) as well as on the cadmium chloride (CdCl₂)–induced reproductive toxicity for 56 days in male rats. Four groups were used: control, Moringa-treated (MOLEE), CdCl₂-treated, and CdCl₂ + MOLEE groups. The reproductive toxicity of CdCl₂ was confirmed; it caused a significant decrease in the accessory sex organ weights, testosterone level, testicular GST level, elevated MDA level (lipid peroxidation indicator), and histopathological alterations in seminiferous tubules, prostate, seminal vesicles, and epididymis as well as sperm characteristics. It also induced downregulation in the expression of StAR and CYP17a genes without change in the expression LHR gene. Eleven active compounds were detected in the GC-MS analysis of MOLEE; six of them have antioxidant properties, and five new compounds presented variable activities. MOLEE alone induced a stimulatory effect on the expression of steroidogenic and LHR genes. It restored the weight of reproductive organs to the control level; however, the recovery in sperm count, motility, abnormalities, percentage of alive sperm, testosterone, and MDA level are still comparable with the control level. Similar findings were also reported at the histological structure of the testes, epididymis, and accessory sex glands. Complete recovery of the GST enzyme activity was observed. Additionally, a restoration in the expression level of the steroidogenic genes was also reported. Our results indicated that the concurrent administration of MOLEE with CdCl₂ can partially mitigate its harmful effects on male fertility.
显示更多 [+] 显示较少 [-]Evaluation of geostatistical techniques and their hybrid in modelling of groundwater quality index in the Marand Plain in Iran
2019
Rostami, Ali Asghar | Isazadeh, Mohammad | Shahabi, Mahmoud | Nozari, Hamed
In many parts of the world, groundwater is considered as one of the main sources of urban and rural drinking water. Over the past three decades, the qualitative and quantitative characteristics of aquifers have been negatively affected by different factors such as excessive use of chemical fertilizers in agriculture, indiscreet, and over-exploitation use of groundwater. Therefore, finding the effective method for mapping the water quality index (WQI) is important for locating suitable and non-suitable areas for urban and rural drinking waters. In the present paper, the best method to estimate the spatial distribution of WQI was assessed using the inverse distance weighted, kriging, cokriging, geographically weighted regression (GWR), and hybrid models. Creating hybrid models can increase modeling capabilities. Hybrid methods make use of a combination of estimated model capabilities. In addition, to improve the results of cokriging, GWR, and hybrid methods, the auxiliary parameters of land slope, groundwater table, and groundwater transmissibility were used. In order to assess the proposed methodology, 11 qualitative parameters obtained from 63 observation wells in Marand Plain (Iran) were utilized. Four statistical measures, namely the root mean square error (RMSE), the mean absolute error (MAE), the Akaike coefficient (AIC), and the correlation coefficient (R²) along with the Taylor diagram, have been done. Classification of the WQI index showed that the quality of a number of 1, 27, 18, and 17 wells was, respectively, in excellent, good, moderate, and poor grades. The results of modeling the WQI index based on IDW, kriging, cokriging, GWR, and hybrid methods showed that the best estimate of WQI was obtained by using hybrid GWR-kriging method with three input parameters of land slope, groundwater table, and groundwater transmissibility. Therefore, hybrid kriging and GWR methods have been fairly well able to simulate the WQI index.
显示更多 [+] 显示较少 [-]Effect of aquatic macrophyte growth on landscape water quality improvement
2019
Zhang, Hengfeng | Zhao, Yixi | Yin, Hang | Wang, Yuanyuan | Li, Huixian | Wang, Zhanshen | Geng, Yongbo | Liang, Wenyan | Wang, Hongjie
The water of urban landscape park is often confronted with microalgal blooms due to its stagnancy. Bioremediation using the combined emergent and submerged plants to control the microalgae growth was investigated in the present study. Two water bodies (Bei and Xin) of Yuyuantan Park in Beijing were selected for the field experiments, and the other lakes with different vegetation of macrophytes were selected as the comparison. The concentrations of chlorophyll a (chl a), chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP), and water temperature and transparency were monitored before and after bioremediation from 2015 to 2017. Results showed that the effects of microalgal inhibition were more significant 2 years after bioremediation. Specifically, the chl a of Dong Lake without any vegetation of macrophytes was up to 65.1 μg/L in summer of 2017, while the Bei and Xin Lakes was only 6.2 and 11.3 μg/L, respectively. In addition, the water quality and transparency also improved, with water bodies being crystal clear. Submerged plants played major roles in microalgal control and water quality improvement, compared to the lakes with only emergent plants. The intensity of humic acid-like substances in three-dimensional fluorescent spectra was stronger for the lakes with submerged plants.
显示更多 [+] 显示较少 [-]Organohalogenated pollutants in raw and UHT cow’s milk from Turkey: a risk assessment of dietary intake
2019
Aydin, Senar | Aydin, Mehmet Emin | Beduk, Fatma | Ulvi, Arzu
In this study, health risk of human exposure to organohalogenated pollutants (OHPs) through milk consumption was determined. Conventionally produced, unprocessed cow’s milk samples taken from Konya District, in Turkey, and 15 different brand ultra-high-temperature (UHT) processed cow’s milk samples taken from supermarkets of Turkey were analyzed for organochlorine pesticides (OCPs, α-, β-, γ-, and δ-HCHs, p,p’-DDE, p,p’-DDD, and p,p’-DDT, heptachlor, heptachlor epoxide, endosulfan I, endosulfan II, endosulfan sulfate, endrin, endrin aldehyde, endrin ketone, aldrin + dieldrin, methoxychlor), polychlorinated biphenyls (PCBs, PCB 28, 52, 101, 153, 138, and 180), and polybrominated diphenyl ethers (PBDEs, PBDE 47, 99, 100, 153, and 154 congeners). Estimated daily intake (EDI) values calculated for both adults and children consuming raw or UHT milk were determined to exceed maximum residue limits (MRLs) set for γ-HCH, ∑Heptachlor, and endrin. EDI values also exceeded admissible daily intake (ADI) values given for ∑HCH, ∑Heptachlor, ∑Endrin aldrin + dieldrin, and ∑PCBs. p,p’-DDT/p,p’-DDE ratio was 1 or higher for 66% of the milk samples, which is an indication of sustaining illegal use of DDT. A health risk is determined for dietary intake of OHPs via consumption of milk.
显示更多 [+] 显示较少 [-]A novel approach for assessing watershed susceptibility using weighted overlay and analytical hierarchy process (AHP) methodology: a case study in Eagle Creek Watershed, USA
2019
Jabbar, Fadhil K. | Grote, Katherine | Tucker, Robert E.
Watershed vulnerability and the characterization of potential risk are important inputs for decision support tools in assessing watershed health. Most previous studies have focused on the assessment of the environmental risk using physicochemical properties of surface water and mathematical models to predict the health of a watershed. Here, we present a new methodology for evaluating watershed vulnerability using the analytic hierarchy process (AHP) and weighted overlay analysis. The new methodology provides an inexpensive approach for assessing areas that need more investigation based on known factors such hydrogeological, geological, and climate parameters without the need for site-specific physicochemical data. The proposed method was implemented using six main factors that influence water quality: land use, soil type, precipitation, slope, depth to groundwater, and bedrock type. Vulnerability was predicted for ten sub-watersheds within the Eagle Creek Watershed in Indiana using publicly available data input into geographic information system. Combination of watershed susceptibility assessment and GIS spatial analysis tools was used to produce the maps that show the susceptible zones within a watershed. A comparison of the resulting vulnerability estimates showed the expected significant positive correlations with measurements of nitrate, phosphate, temperature, and electrical conductivity. Likewise, the vulnerability estimates negatively correlated with dissolved oxygen and E. coli. Furthermore, the validation of the proposed approach revealed that the areas predicted to have high vulnerability did have lower water quality indices; the results showed a high negative correlation (r² = 0.77, p < 0.05) between water quality index (WQI) and vulnerability which strongly suggests this method can be used successfully to assess a watershed’s susceptibility.
显示更多 [+] 显示较少 [-]Study of optimal conditions in semi-continuous anaerobic co-digestion of table olive effluents and pig manure in a perfectly stirred reactor
2019
González, Juan F. | Parralejo, Ana I. | Bolívar, Heidi M. | Gonzalez, Jeronimo
Brines from table olive elaboration were co-digested with pig manure, obtaining high methane productions. In particular, the methane yields obtained for pig manure total solid (TS) initial concentrations of 2%, 7%, 9% (wet basis, wt.) were 106, 213 and 247 mL CH₄ gVS⁻¹ₐdd, respectively, using mixtures of two types of brine (acid (A) and basic (B)) generated in the elaboration process. Moreover, an experiment with only basic brine was made, using a pig manure TS concentration of 7% wt. In this case, a methane yield of 224 mL CH₄ gVS⁻¹ₐdd was obtained. The methane production rate was calculated in experiments of 7% pig manure TS concentration and a high kinetic constant of 0.31 d⁻¹ was obtained for the mixture of residual brine. Finally, the effect of Na⁺ cation concentration was evaluated in the mixture A:B during co-digestion processes with a 7% wt. pig manure TS concentration and inhibition was detected in this process with a [Na⁺] of 0.56% wt. of the total sample. An energy and economical study on the treatment of these wastewaters by means of anaerobic co-digestion demonstrated a great economic benefit for the producer industry, a reduction in the diesel consumption used to produce its energetic demand and a reduction cost of 3.63 €/m³ generated of A:B brines mixture with ratio 2:1.
显示更多 [+] 显示较少 [-]Indoor formaldehyde removal by three species of Chlorphytum Comosum under the long-term dynamic fumigation system
2019
Li, Jian | Zhong, Jiaochan | Zhan, Ting | Liu, Qinghui | Yan, Liushui | Lu, Mingming
Gaseous formaldehyde removal efficiency and physiological characteristics of leaves were investigated through a dynamic fumigation system. Three different species of potted Chlorophytum Comosum, (Green Chlorophytum Comosum for its green leaves), CC (Combined the leaves of Chlorophytum Comosum with leaves half green and half white) and PC (Purple Chlorophytum Comosum for its purple leaves), were exposed to formaldehyde for 7 days. The results showed formaldehyde removal efficiencies in the daytime were 71.07% ± 0.23, 84.66% ± 0.19, and 46.73% ± 0.15 at 1 ppm for GC, CC, and GC plants, respectively, and were 36.21% ± 0.24, 62.15% ± 0.19, and 34.97% ± 0.11 at night. This might be due to higher plant physiological activities (e.g., photosynthesis, respiration, and transpiration) during the daytime than at night. Ten physiological indicators of leaves were chosen to evaluate the 7-day fumigation process, which were chlorophyll, free protein, relative conductivity, malondialdehyde (MDA), hydrogen peroxide (H₂O₂), hydroxyl radical, superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and total antioxidant capacity (T-AOC). Eight of these indicators increased, while chlorophyll decreased by 22.16%, 6.95%, and 25.32%, and CAT decreased by 18.9%, 17.8%, and 25.30% for GC, CC, and PC respectively. Among all the increasing physiological indicators, relative conductivity and MDA showed the greatest increase by 279.32% and 155.56% for PC. A 15-day recovery study was also conducted using MDA and T-AOC as indicators. The results showed that all the tested plants could be tolerant up to the 8 ppm of formaldehyde concentration for 7 days under dynamic fumigation and needed 10–15 days for self-recovery.
显示更多 [+] 显示较少 [-]Scale and process design for sewage treatment plants in airports using multi-objective optimization model with uncertain influent concentration
2019
Yao, Liming | He, Linhuan | Chen, Xudong
The treatment of airport sewage has posed many novel challenges because of its huge impact on the surrounding environment. This paper proposes a multi-objective decision model to optimize the scale design and process selection of sewage treatment plants in airports. In this model, we consider the conflict among the process cost, environmental protection, and benefits of recycled water. In addition, the uncertainty in influent concentration and passenger throughput is also incorporated. Airport sewage treatment has its own unique features, such as the concentration of airport sewage is higher than that of ordinary urban sewage, the change in passenger throughput impacts the volume of the airport sewage treatment, and the utilization rate of the entire sewage treatment plant must be higher than or equal to 70%. Only in this case can the airport sewage treatment plant pass the acceptance test. The Tianfu International Airport, the largest civil transportation hub airport project in southwestern China, is used to prove the efficiency of the proposed model. Finally, some significant insights are suggested for the design of wastewater treatment plants in airports.
显示更多 [+] 显示较少 [-]Procaine penicillin alters swimming behaviour and physiological parameters of Daphnia magna
2019
Bownik, Adam | Ślaska, Brygida | Bochra, Justyna | Gumieniak, Katarzyna | Gałek, Kinga
Procaine penicillin (PP) is a β-lactam antibiotic widely used in human and veterinary medicine. Although PP is detected in surface water, little is known on its effects on aquatic invertebrates. Our aim was to determine the influence of PP on swimming behaviour (track density, swimming speed, turning angle, hopping frequency) and physiological activity (oxygen consumption, heart rate, thoracic limb movement) of a freshwater invertebrate Daphnia magna exposed to PP at concentrations of 11.79 mg/L, 117.9 mg/L and 1179 mg/L for 2 h and 24 h. The results showed no mortality; however, reduction of swimming activity manifested by the decreased track density, swimming speed and turning angle noted in Daphnia exposed to all the concentrations of PP. Increase of oxygen consumption was observed after 2-h exposure; however, decrease of this parameter was found after 24 h. PP also reduced heart rate and thoracic limb movement in a concentration-dependent manner. The results suggest that the antibiotic should not induce mortality; however, it may affect swimming behaviour and physiological parameters of Daphnia magna particularly inhabiting aquaculture facilities with intensive antibiotic treatment. On the basis of the present results, we also suggest higher sensitivity of behavioural and physiological parameters of cladocerans than the commonly used endpoints: mortality or immobilisation and their possible application as a part of early warning systems in monitoring of surface water toxicity.
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