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How safe are the new green energy resources for marine wildlife? The case of lithium
2020
Viana, Thainara | Ferreira, Nicole | Henriques, Bruno | Leite, Carla | De Marchi, Lucia | Amaral, Joana | Freitas, Rosa | Pereira, Eduarda
Considering the increasing use of Lithium (Li) and the necessity to fulfil this demand, labile Li occurrence in the environment will be enhanced. Thus, additional research is needed regarding the presence of this element in marine environment and its potential toxic impacts towards inhabiting wildlife. The aim of the present study was to evaluate Li toxicity based on the exposure of Mytilus galloprovincialis to this metal, assessing the biochemical changes related with mussels’ metabolism, oxidative stress and neurotoxicity. For this, organisms were exposed to different Li concentrations (100, 250, 750 μg/L) for 28 days. The results obtained clearly demonstrated that Li lead to mussels’ metabolism depression. The present study also revealed that, especially at the highest concentrations, antioxidant and biotransformation enzymes were not activated, leading to the occurrence of lipid peroxidation and loss of redox homeostasis, with increased content in oxidized glutathione in comparison to the reduced form. Furthermore, after 28 days, higher Li exposure concentrations induced neurotoxic effects in mussels, with a decrease in acetylcholinesterase enzyme activity. The responses observed were closely related with Li concentrations in mussels’ tissues, which were more pronounced at higher exposure concentrations. Such results highlight the potential toxic effects of Li to marine species, which may even be higher under predicted climate changes and/or in the presence of other pollutants.
Show more [+] Less [-]Waste-to-energy nexus: A sustainable development
2020
Sharma, Surbhi | Basu, Soumen | Shetti, Nagaraj P. | Kamali, Mohammadreza | Walvekar, Pavan | Aminabhavi, Tejraj M.
An upsurge in global population due to speedy urbanization and industrialization is facing significant challenges such as rising energy-demand, enormous waste-generation and environmental deterioration. The waste-to-energy nexus based on the 5R principle (Reduce, Reuse, Recycle, Recovery, and Restore) is of paramount importance in solving these Gordian knots. This review essentially concentrates on latest advancements in the field of ‘simultaneous waste reduction and energy production’ technologies. The waste-to-energy approaches (thermal and biochemical) for energy production from the agricultural residues are comprehensively discussed in terms environmental, techno-economic, and policy analysis. The review will assess the loopholes in order to come up with more sophisticated technologies that are not only eco-friendly and cost-effective, but also socially viable. The waste-to-energy nexus as a paradigm for sustainable development of restoring waste is critically discussed considering future advancement plans and agendas of the policy-makers.
Show more [+] Less [-]A facile approach for rapid on-site screening of nicotine in natural tobacco
2020
Yu, Chaofan | Yu, Jie | Zhang, Huirong | He, Ziyan | Sha, Yunfei | Liu, Baizhan | Wang, Ying
Nicotine (Nic) exposed to the environment which comes from tobacco products is the main addictive agent and specific classes of hazardous compound that merit concern. In this study, we have established a fast and reliable method to achieve specific detection of Nic in natural nicotiana tabacum within 30 s through a miniaturized platform based on screen printed gold electrode (SPE). A simple electrochemical pretreatment mean was employed on gold surface that led to the exposure of Au (111) facet and a convenient sample pretreatment method was adopted to realize the extraction of Nic in tobacco. The present electrochemical sensor exhibits an ample range of sensing from 10 μg/g to 200 μg/g, which is able to compliance with tobacco industry testing standards of actual samples. Over 60 sampling points from different origins in China or other countries were performed with direct analysis using this method and satisfactory results have been obtained. The proposed approach was demonstrated to be a very promising platform for significantly improving analytical efficiency in laboratories as well as for monitoring the source reduction control of Nic in the environment.
Show more [+] Less [-]Monitoring and environmental risk assessment of pesticide residues and some of their degradation products in natural waters of the Spanish vineyard region included in the Denomination of Origin Jumilla
2020
Herrero-Hernández, Eliseo | Simón-Egea, Ana B. | Sánchez-Martín, María J. | Rodríguez-Cruz, M Sonia | Andrades, M Soledad
Water pollution by pesticides used in agriculture is currently a major concern both in Spain and in Europe as a whole, prompting the need to evaluate water quality and ecological risk in areas of intensive agriculture. This study involved monitoring pesticide residues and certain degradation products in surface and ground waters of the Denomination of Origin (DO) Jumilla vineyard area in Spain. Sixty-nine pesticides were selected and evaluated at twenty-one sampling points using a multi-residue analytical method, based on solid-phase extraction (SPE) and analysis by liquid chromatography coupled with mass spectrometry (LC-MS), providing reliable results. Twenty-six compounds from those selected were detected in the samples analyzed (eleven insecticides including one degradation product, nine herbicides, and six fungicides) and fifteen of them were found in concentrations over 0.1 μg L⁻¹ (upper threshold established by the EU for pesticides detected in waters for human consumption). Indoxacarb was present in more than 70% of the samples, being the most frequently detected compound in water samples. Some pesticides were ubiquitous in all the water samples. Ecotoxicological risk indicators, toxic units (TUs) and risk quotients (RQs), for algae, Daphnia magna and fish were calculated to estimate the environmental risk of the presence of pesticides in waters. The compounds with the highest risk were the herbicides pendimethalin, with RQ values > 1 for the three aquatic organisms, and diflufenican, posing a high risk for algae and fish, and the insecticide chlorpyrifos, with a high risk for Daphnia magna and fish. The ∑TUi determined for water at each sampling point posed only a high risk for the three aquatic organisms in a sample. These results are important for considering the selection of pesticides with less environmental risk in intensive agricultural areas.
Show more [+] Less [-]Combined effect of polystyrene microplastics and dibutyl phthalate on the microalgae Chlorella pyrenoidosa
2020
Li, Zhaochuan | Yi, Xianliang | Zhou, Hao | Chi, Tongtong | Li, Wentao | Liu, Kaiming
The combined effect of polystyrene microplastics (mPS) and dibutyl phthalate (DBP), a common plastic additive, on the microalgae Chlorella pyrenoidosa was investigated in the present study. The 96 h-IC₅₀ value of DBP was 2.41 mg L⁻¹. Polystyrene microplastics exhibited size-dependent inhibitory effect to C. pyrenoidosa, with the 96 h-IC₅₀ at 6.90 and 7.19 mg L⁻¹ for 0.1 and 0.55 μm mPS respectively, but little toxicity was observed for 5 μm mPS. The interaction parameter ρ based on the response additive response surface (RARS) model varied from −0.309 to 5.845, indicating the interaction pattern varying with exposure concentrations of chemical mixtures. A modified RARS model (taking ρ as a function of exposure concentration) was constructed and could well predict the combined toxicity of mPS and DBP. More than 20% reduction of DBP was observed at 20 mg L⁻¹ mPS, while 1 mg L⁻¹ mPS had no significant effect on the bioavailability of DBP at different sampling time points. Volume, morphological complexity and chlorophyll fluorescence intensity of microalgal cells were disturbed by both DBP and mPS. The antagonistic effect of high concentrations of mPS might be partially attributed to the combination of hetero- and homo-aggregation and the reduced bioavailability of DBP. The overall findings of the present study profiled the combined toxic effects of mPS and DBP on marine phytoplankton species which will be helpful for further evaluation of ecological risks of mPS and DBP in marine environment.
Show more [+] Less [-]Occurrence, distribution, and risk assessment of pharmerciuticals in wastewater and open surface drains of peri-urban areas: Case study of Juja town, Kenya
2020
Muriuki, Cecilia W. | Home, Patrick G. | Raude, James M. | Ngumba, Elijah K. | Munala, Gerryshom K. | Kairigo, Pius K. | Gachanja, Anthony N. | Tuhkanen, Tuula A.
The occurrence of Active Pharmaceutical Ingredients (APIs) in the environment is becoming a major area of concern due to their undesirable effects on non-target organisms. This study investigated the occurrence and risk of contamination by five antibiotics and three antiretrovirals drugs in a fast-growing peri-urban area in Kenya, with inadequate sewer system coverage. Due to poor sewage connectivity and poorly designed decentralized systems, wastewater is directly released in open drains. Water and sediment samples were collected from open surface water drains, while wastewater samples were collected from centralized wastewater treatment plants (WWTP). Solid-phase extraction and ultrasonic-assisted extraction for the aqueous and sediment samples respectively were carried out and extracts analyzed by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) using isotopically labeled internal standards. APIs were observed with the detection frequency ranging from 36% to 100%. High mean concentrations of 48.7 μg L⁻¹, 108 μg L⁻¹, and 532 μg L⁻¹ were observed in surface drains for Lamivudine (3 TC), Sulfamethoxazole (SMX), Ciprofloxacin (CIP) respectively. Drain sediments also showed high concentrations of APIs ranging from 2.1 to 13,100 μg kg⁻¹. APIs in this study exceeded those observed in existing literature studies. JKUAT WWTP removal efficiencies varied from −90.68% to 72.67%. Total APIs emission load of the study area was 3550 mg d⁻¹ with WWTP effluent contributing higher loads (2620 mg d⁻¹) than surface water drains (640 mg d⁻¹). Zidovudine (ZDV), nevirapine (NVP), and trimethoprim (TMP) loads in drains, however, exceeded WWTP effluent. Low to high ecotoxicity risk of the individual APIs were observed to the aquatic environment, with high risks for the development of antibiotic resistance in microbiome as determined by the risk quotient (RQ) approach. Risk management through efficient wastewater collection, conveyance, and treatment is necessary to suppress the measured concentrations.
Show more [+] Less [-]Importance of the structure and micropores of sedimentary organic matter in the sorption of phenanthrene and nonylphenol
2020
Xu, Decheng | Hu, Shujie | Xiong, Yongqiang | Yang, Yu | Ran, Yong
The demineralized fraction (DM), lipid-free fraction (LF), nonhydrolyzable organic carbon fraction (NHC), and black carbon (BC) were isolated from five marine surface sediments, and they were characterized by elemental analysis as well as CO₂ and N₂ adsorption techniques, respectively. The NHC fractions were characterized using advanced solid-state ¹³C nuclear magnetic resonance (NMR) and x-ray photoelectron spectroscopy (XPS). Then, the sorption isotherms of phenanthrene (Phen) and nonylphenol (NP) on all of the samples were investigated by a batch technique. The CO₂ micropore volumes were corrected for the outer specific surface areas (SSAs) by using the N₂-SSA. Significant correlations between the micropore-filling volumes of Phen and NP and the micropore volumes suggested that the micropore-filling mechanism dominated the Phen and NP sorption. Meanwhile, the (O + N)/C atomic ratios were negatively and significantly correlated with the sorption capacities of Phen and NP, indicating that the sedimentary organic matter (SOM) polarity also played a significant role in the sorption process. In addition, a strong linear correlation was demonstrated between the aromatic C and the sorption capacity of Phen for the NHC fractions. This study demonstrates the importance of the micropores, polarity, and aromaticity on the sorption processes of Phen and NP in the sediments.
Show more [+] Less [-]Assessment of cadmium and lead contamination in rice farming soils and rice (Oryza sativa L.) from Guayas province in Ecuador
2020
Ochoa, Martín | Tierra, Wladimir | Tupuna-Yerovi, Diego Santiago | Guanoluisa, Danilo | Otero, Xosé Luis | Ruales, Jenny
Rice is the world’s most consumed and in-demand grain. Ecuador is one of the main rice-consuming countries in Latin America, with an average per capita consumption of 53.2 kg per year. Rice cultivation takes place under flooding conditions, which favors the mobilization and subsequent accumulation of heavy metals in the plant. This study’s principal objective was to evaluate the contamination of cadmium (Cd) and lead (Pb) in the rice cultivation system in the province of Guayas. To this end, extensive sampling of water, soil and rice grains was carried. Water samples were analyzed to determine physicochemical properties and concentrations of dissolved Cd and Pb. Physicochemical properties, total organic carbon (TOC), total content of nitrogen (N), iron (Fe), manganese (Mn), phosphorus (P), bioavailable phosphorus (P mehlich), Cd and Pb were determined in soil samples. In addition, to understand the dynamics of Cd and Pb mobility and bioavailability, an extraction of six randomly selected soil samples was carried out. The concentration values of the total Cd and Pb content in the rice cultivation system did not exceed the maximum recommended limit for soil, water and rice grains. However, 85% of the total Cd was in the soluble or exchangeable fraction of the soil, while the Pb was strongly bound to crystalline iron oxyhydroxides. It was established that the TOC, N, Fe, and P mehlich have a significant correlation (p < 0.05) with the overall concentration of Cd and Pb in the rice farming soil. The Cd and Pb present in rice do not represent a dietary health risk to the population of Ecuador.
Show more [+] Less [-]Glyphosate exposures and kidney injury biomarkers in infants and young children
2020
Trasande, Leonardo | Aldana, Sandra India | Trachtman, Howard | Kannan, Kurunthachalam | Morrison, Deborah | Christakis, Dimitri A. | Whitlock, Kathryn | Messito, Mary Jo | Gross, Rachel S. | Karthikraj, Rajendiran | Sathyanarayana, Sheela
The goal of this study was to assess biomarkers of exposure to glyphosate and assess potential associations with renal function in children. Glyphosate is used ubiquitously in agriculture worldwide. While previous studies have indicated that glyphosate may have nephrotoxic effects, few have examined potential effects on kidney function in children. We leveraged three cohorts across different phases of child development and measured urinary levels of glyphosate. We evaluated associations of glyphosate with three biomarkers of kidney injury: albuminuria (ACR), neutrophil gelatinase-associated lipocalin (NGAL), and kidney injury marker 1 (KIM-1). Multivariable regression analyses examined associations of glyphosate with kidney injury biomarkers controlling for covariates. We identified glyphosate in 11.1% of the total participants. The herbicide was detected more frequently in the neonate population (30%). Multivariable regression models failed to identify significant associations of log-transformed glyphosate with any of the kidney injury biomarkers, controlling for covariates age, sex, and maternal education. While we confirm detectability of glyphosate in children’s urine at various ages and stages of life, there is no evidence in this study for renal injury in children exposed to low levels of glyphosate. Further studies of larger sample size are indicated to better understand putative deleterious effects of the herbicide after different levels of exposure.
Show more [+] Less [-]Exposure of U.S. population to endocrine disruptive chemicals (Parabens, Benzophenone-3, Bisphenol-A and Triclosan) and their associations with female infertility
2020
Arya, Sushila | Dwivedi, Alok Kumar | Alvarado, Luis | Kupesic-Plavsic, Sanja
Ubiquitous exposure to endocrine disruptive chemicals (EDC) among women of reproductive age is alarming. Exposure to EDCs could be contributing to infertility. We determined the association between common EDCs and self-reported infertility among U.S. women, 18–45 years of age using the National Health and Nutrition Examination Surveys (NHANES) for periods 2013–2014 and 2015–2016. A cross-sectional study on reproductive age women was conducted. Available important sociodemographic variables, and urinary concentrations of parabens (methyl paraben [MP], ethyl paraben [EP], propyl paraben [PP], and butyl paraben [BP]), Benzophenone-3 (BP-3), Bisphenol-A (BPA), and triclosan (TCS) were obtained from the NHANES databases. Clustering among EDCs were obtained using variable cluster analysis. Relative risk regression models were used to estimate associations of individual and combined EDCs with self-reported infertility after applying appropriate survey weights to account for the complex survey design as well as to compensate for the four-year cycle. Results were summarized using prevalence ratio (PR) with 95% confidence interval (CI). Of total 789 individuals included in the study, 14% (95%CI: 11%–18%) had infertility. MP and PP were detected in 99% of urine samples, BP in 46%, EP and BP-3 in 96%, BPA in 94% and TCS in 73%. Self-reported infertility was significantly associated with combined score of BP-3, BPA and TCS (PR = 1.13, p = 0.007), and above detection level of EP (PR = 1.57, p = 0.025) even after adjusting for potential confounders. Our results suggested the EP and mixtures of benzophenones, TCS, and BPA were associated with infertility among the U.S. women. However, because of the limitations inherent to the cross-sectional study design, prospective cohort studies are warranted to confirm these findings.
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