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Colony field test reveals dramatically higher toxicity of a widely-used mito-toxic fungicide on honey bees (Apis mellifera) Full text
2021
Fisher, Adrian | DeGrandi-Hoffman, Gloria | Smith, Brian H. | Johnson, Meredith | Kaftanoglu, Osman | Cogley, Teddy | Fewell, Jennifer H. | Harrison, Jon F.
Honey bees (Apis mellifera) and other pollinator populations are declining worldwide, and the reasons remain controversial. Based on laboratory testing, fungicides have traditionally been considered bee-safe. However, there have been no experimental tests of the effects of fungicides on colony health under field conditions, and limited correlational data suggests there may be negative impacts on bees at levels experienced in the field. We tested the effects of one of the most commonly used fungicides on colony health by feeding honey bee colonies pollen containing Pristine® (active ingredients: 25.2% boscalid, 12.8% pyraclostrobin) at four levels that bracketed concentrations we measured for pollen collected by bees in almond orchards. We also developed a method for calculating per-bee and per-larva dose. Pristine® consumption significantly and dose-dependently reduced worker lifespan and colony population size, with negative health effects observed even at the lowest doses. The lowest concentration we tested caused a 15% reduction in the worker population at an estimated dosage that was three orders of magnitude below the estimated LD₁₅ values for previous acute laboratory studies. The enhanced toxicity under field conditions is at least partially due to activation of colonial nutritional responses missed by lab tests. Pristine® causes colonies to respond to perceived protein malnutrition by increasing colony pollen collection. Additionally, Pristine induces much earlier transitioning to foraging in individual workers, which could be the cause of shortened lifespans. These findings demonstrate that Pristine® can negatively impact honey bee individual and colony health at concentrations relevant to what they experience from pollination behavior under current agricultural conditions.
Show more [+] Less [-]ZIF-8 templated assembly of La3+-anchored ZnO distorted nano-hexagons as an efficient active photocatalyst for the detoxification of rhodamine B in water Full text
2021
Karuppasamy, K. | Rabani, Iqra | Vikraman, Dhanasekaran | Bathula, Chinna | Theerthagiri, J. | Bose, Ranjith | Yim, Chang-Joo | Kathalingam, A. | Seo, Young-Soo | Kim, Hyun-Seok
The use of lanthanum-anchored zinc oxide distorted hexagon (La@ZnO DH) nanoclusters as an active material for the photodegradation of rhodamine B (Rh–B) dye via hydrogen bonding, electrostatic, and π-π interactions is examined herein. The active photocatalyst is derived from porous zeolite imidazole frameworks (ZIF-8) via a combined ultrasonication and calcination process. The distorted hexagon nanocluster morphology with controlled surface area is shown to provide excellent catalytic activity, chemical stability and demarcated pore volume. In addition, the low bandgap (3.57 eV) of La@ZnO DH is shown to expand the degradation of Rh–B under irradiation of UV light as compared to the pristine ZIF-8-derived ZnO photocatalyst due to inhibited recombination of electrons and holes. The outstanding physicochemical stability and enhanced performance of La@ZnO DH could be ascribed to the synergistic interaction among La3+ particles and the ZnO nanoclusters and provide a route for their utilization as a promising catalyst for the detoxification of Rh–B.
Show more [+] Less [-]Ferrihydrite–organo composites are a suitable analog for predicting Cd(II)–As(V) coexistence behaviors at the soil solid-liquid interfaces Full text
2021
Du, Huihui | Nie, Ning | Rao, Wenkai | Lü, Lei | Lei, Ming | Tie, Boqing
Organomineral assemblages are building units of soil micro-aggregates and exert their essential roles in immobilizing toxic elements. Currently, our knowledge of the adsorption and partitioning behaviors of coexisting Cd–As onto organomineral composites is limited. Herein, we carefully studied Cd–As cosorption onto ferrihydrite organomineral composites made with either living or non-living organics, i.e., bacteria (Delftia sp.) or humic acid (HA), using batch adsorption and various spectroscopies. Batch results show that As(V) only enhances Cd(II) sorption on pure Fh at pH < 6 but cannot promote Cd(II) sorption to Fh–organo composites. However, Cd(II) noticeably promotes As(V) sorption at pH>~5–6. Synchrotron micro X-ray fluorescence indicates that Cd(II) adsorbs predominately to the bacterial fraction (Cd versus P, r = 0.924), whereas As(V) binds mainly to the Fh fraction (As versus Fe, r = 0.844) of the Fh–bacteria composite. On Fh–HA composite, however, Cd(II) and As(V) are both primarily sorbed by the Fh fraction (Cd/As versus P, r > 0.8), based on the scanning transmission electron microscopy-energy disperse spectroscopy analyses. Elemental distribution characterization also manifests the co-localization of Cd(II) and As(V) within the organomineral composite, particular in Fh–HA composite (Cd versus As, r = 0.8), which is further identified as the Fh–As–Cd ternary complex based on the observations (higher frequencies at ~753–761 cm⁻¹) of attenuated total reflection Fourier-transform infrared spectroscopy. Moreover, this ternary interaction is more pronounced in Fh–HA than in Fh–bacteria. In summary, our results suggest that Cd–As coadsorption behaviors on Fh–organo composites are different from those on pure minerals, and the presence of bacteria/HA can significantly affect metal (loid)s speciation, distribution, and ternary interaction. Therefore organomineral composites are a more suitable analog than pure mineral phases to predict the mobility and fate of Cd–As in natural environments.
Show more [+] Less [-]Potential effects of biodegradable single-use items in the sea: Polylactic acid (PLA) and solitary ascidians Full text
2021
Anderson, Guillermo | Shenkar, Noa
With conventional plastics posing a great threat to marine organisms, and potentially also to humans, bio-based, biodegradable plastics are being offered as an ecological solution by which to reduce the environmental impact. Inside compost facilities, bioplastics that comply with the EN 13432:2000 international standard biodegrade almost completely within 180 days. However, outside compost facilities, and specifically in marine environments, these bioplastics may have a similar effect to that of fossil-fuel based plastics. Here we investigated the effects of polyethylene terephthalate (PET) and polylactic acid (PLA) single-use cups and plates on a solitary ascidian’s biological and ecological features. Both PET and PLA microparticles reduced the fertilization rate of Microcosmus exasperatus, with no significant difference between materials. Accumulation rates in adult M. exasperatus exposed to micronized PET and PLA particles at two concentrations were similar for both the bioplastic material and the conventional plastic particles, with no significant difference between the two materials. A microbial-based digestive protocol was developed in order to recover the bioplastic material from ascidian tissue and reduce any material-loss caused by the known digestion protocols. Finally, PET plates submerged for three months in the Red Sea exhibited a significantly higher community richness and cover area in comparison to PLA plates, which did not provide a firm substrate for settlers. Indeed, coverage by the solitary ascidian Herdmania momus was significantly higher on PET plates. The current study demonstrates that discarded bioplastic products may have similar effects to those of conventional plastics on marine organism fertilization and biological accumulation, emphasizing the need to revise both the production and marketing of “biodegradable” and “compostable” plastics in order to prevent a further negative impact on ecosystems due to the mismanagement of bioplastic products.
Show more [+] Less [-]SARS-CoV-2 in water services: Presence and impacts Full text
2021
Langone, M. | Petta, L. | Cellamare, C.M. | Ferraris, M. | Guzzinati, R. | Mattioli, D. | Sabia, G.
The occurrence of human pathogenic viruses in aquatic ecosystems and, in particular, in internal water bodies (i.e., river, lakes, groundwater, drinking water reservoirs, recreational water utilities, and wastewater), raises concerns regarding the related impacts on environment and human health, especially in relation to the possibility of human exposure and waterborne infections. This paper reviews the current state of knowledge regarding severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) presence and persistence in human excreta, wastewaters, sewage sludge as well as in natural water bodies, and the possible implications for water services in terms of fecal transmission, public health, and workers’ risk. Furthermore, the impacts related to the adopted containment and emergency management measures on household water consumptions are also discussed, together with the potential use of wastewater-based epidemiology (WBE) assessment as a monitoring and early warning tool, to be applied in case of infectious disease outbreaks. The knowledge and tools summarized in this paper provide a basic information reference, supporting decisions makers in the definition of suitable measures able to pursue an efficient water and wastewater management and a reduction of health risks. Furthermore, research questions are provided, in order to direct technical and public health communities towards a sustainable water service management in the event of a SARS-CoV-2 re-emergence, as well as a future deadly outbreak or pandemic.
Show more [+] Less [-]Behavioral changes occur earlier than redox alterations in developing zebrafish exposed to Mancozeb Full text
2021
Paganotto Leandro, Luana | Siqueira de Mello, Renata | da Costa- Silva, Dennis Guilherme | Medina Nunes, Mauro Eugênio | Rubin Lopes, Andressa | Kemmerich Martins, Illana | Posser, Thaís | Franco, Jeferson Luis
As agriculture expands to provide food and wellbeing to the world’s growing population, there is a simultaneous increasing concern about the use of agrochemicals, which can harm non-target organisms, mainly in the aquatic environment. The fungicide Mancozeb (MZ) has been used on a large-scale and is a potent inducer of oxidative stress. Therefore, there is an urgent need for the development of more sensitive biomarkers designed to earlier biomonitoring of this compound. Here we tested the hypothesis that behavioral changes induced by sublethal MZ concentrations would occur first as compared to biochemical oxidative stress markers. Embryos at 4 h post-fertilization (hpf) were exposed to Mancozeb at 5, 10 and 20 μg/L. Controls were kept in embryo water only. Behavioral and biochemical parameters were evaluated at 24, 28, 72, and 168 hpf after MZ exposure. The results showed that MZ significantly altered spontaneous movement, escape responses, swimming capacity, and exploratory behavior at all exposure times. However, changes in ROS steady-stead levels and the activity of antioxidant enzymes were observable only at 72 and 168 hpf. In conclusion, behavioral changes occurred earlier than biochemical alterations in zebrafish embryos exposed to MZ, highlighting the potential of behavioral biomarkers as sensitive tools for biomonitoring programs.
Show more [+] Less [-]VIRS based detection in combination with machine learning for mapping soil pollution Full text
2021
Jia, Xiyue | O’Connor, David | Shi, Zhou | Hou, Deyi
Widespread soil contamination threatens living standards and weakens global efforts towards the Sustainable Development Goals (SDGs). Detailed soil mapping is needed to guide effective countermeasures and sustainable remediation operations. Here, we review visible and infrared reflectance spectroscopy (VIRS) based detection methods in combination with machine learning. To date, proximal, airborne and spaceborne carrier devices have been employed for soil contamination detection, allowing large areas to be covered at low cost and with minimal secondary environmental impact. In this way, soil contaminants can be monitored remotely, either directly or through correlation with soil components (e.g. Fe-oxides, soil organic matter, clay minerals). Observed vegetation reflectance spectra has also been proven an effective indicator for mapping soil pollution. Calibration models based on machine learning are used to interpret spectral data and predict soil contamination levels. The algorithms used for this include partial least squares regression, neural networks, and random forest. The processes underlying each of these approaches are outlined in this review. Finally, current challenges and future research directions are explored and discussed.
Show more [+] Less [-]Ecotoxicological effects of traffic-related metal sediment pollution in Lumbriculus variegatus and Gammarus sp Full text
2021
Kontchou, Julios A. | Nachev, Milen | Sures, Bernd
To reduce direct discharges of surface runoff to receiving waters, separate sewer systems have been implemented, with runoff retention basins (RRB) for pollutant pretreatment by sedimentation and infiltration. However, due to frequent and intense precipitation events, most RRBs are overwhelmed by runoff resulting in overflow into the receiving freshwater bodies. Hence, the present study evaluates the impact of traffic-related runoff overflow on metal concentrations in sediment and Gammarus sp. Downstream of the RRB outfall in the receiving stream. Samples were collected from the RRB, upstream (reference site) and at different distances downstream from the RRB outfall in the stream. The samples were analyzed for the presence and distribution of metals using ICP-MS. Furthermore, ecotoxicological effects of the overflow on benthic species were assessed using Lumbriculus variegatus exposed to the field sediments. Our findings reveal that overflow of the RRB results in elevated traffic-related metal concentrations in sediment and biota of the stream. Within the first 50 m downstream increased sediment metal concentrations were found. The gammarids downstream of the RRB outfall showed an increased accumulation of several metals. Similarly, the metals were found to be taken up by the endobenthic L. variegatus under laboratory conditions and the bioaccumulation pattern was related to the sediment concentrations. Bioaccumulation by both organisms is an indication that overflow of the RRB also leads to uptake of increased element amounts in organisms downstream. Laboratory-based studies addressing standard toxicity endpoints showed no clear toxic effects on growth and reproduction. However, elevated levels of metallothioneins were measured in the annelids during the test period. This indicates a physiological response induced by increased metal concentrations due to RRB overflow. Hence, the results of this study show that discharges by the RRB increase the metal concentration in the receiving stream with the possibility of adverse effects on organisms.
Show more [+] Less [-]The environmental risks of pharmaceuticals beyond traditional toxic effects: Chemical differences that can repel or entrap aquatic organisms Full text
2021
Jacob, Raquel Sampaio | Araújo, Cristiano V.M. | Santos, Lucilaine Valéria de Souza | Moreira, Victor Rezende | Lebron, Yuri Abner Rocha | Lange, Liséte Celina
The environmental risks of pharmaceuticals beyond traditional toxic effects: Chemical differences that can repel or entrap aquatic organisms Full text
2021
Jacob, Raquel Sampaio | Araújo, Cristiano V.M. | Santos, Lucilaine Valéria de Souza | Moreira, Victor Rezende | Lebron, Yuri Abner Rocha | Lange, Liséte Celina
The aim of the present study was to assess the risks of four different pharmaceutical active compounds (PhACs; diazepam, metformin, omeprazole and simvastatin). Acute and chronic toxicities were studied using the bacterium Aliivibrio fischeri and the microalgae Pseudokirchneriella subcapitata; while the repellency and attractiveness were assessed by avoidance tests with juvenile Cypirinus carpio using a multi-compartmented exposure system. Omeprazole was found to be an acutely toxic drug (EC₅₀: 0.015 mg/L), while the other PhACs, except simvastatin, showed some chronic toxicity. Regarding avoidance, simvastatin and omeprazole induced an escape response for 50% of the fish population at 0.032 and 0.144 mg/L, respectively; contrarily, diazepam was attractive, even at lethal concentrations, representing a dangerous trap for organisms. The toxicity of the PhACs seemed not to be directly related to their repellency; and the mode of action seems to determine the repellency or attractiveness of the chemicals. Contamination by PhACs is of concern due to the environmental disturbance they might cause, either due to their acute and chronic toxicity (at the individual level), repellency (at the ecosystem level: loss of local biodiversity) or attraction to potentially lethal levels.
Show more [+] Less [-]The environmental risks of pharmaceuticals beyond traditional toxic effects: Chemical differences that can repel or entrap aquatic organisms Full text
2021
Sampaio Jacob, Raquel | Araújo, Cristiano V. M. | Santos, Lucilaine Valéria Souza de | Rezende Moreira, Victor | Rocha Lebron, Yuri Abner | Lamge, Liséte Celina | Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (Brasil) | Conselho Nacional das Fundaçôes Estaduais de Amparo à Pesquisa (Brasil) | Fundação de Amparo à Pesquisa do Estado de São Paulo Minas Gerais | Universidade Federal de Minas Gerais | Ministerio de Ciencia, Innovación y Universidades (España) | Agencia Estatal de Investigación (España) | Consejo Superior de Investigaciones Científicas [https://ror.org/02gfc7t72]
The aim of the present study was to assess the risks of four different pharmaceutical active compounds (PhACs; diazepam, metformin, omeprazole and simvastatin). Acute and chronic toxicities were studied using the bacterium Aliivibrio fischeri and the microalgae Pseudokirchneriella subcapitata; while the repellency and attractiveness were assessed by avoidance tests with juvenile Cypirinus carpio using a multi-compartmented exposure system. Omeprazole was found to be an acutely toxic drug (EC50: 0.015 mg/L), while the other PhACs, except simvastatin, showed some chronic toxicity. Regarding avoidance, simvastatin and omeprazole induced an escape response for 50% of the fish population at 0.032 and 0.144 mg/L, respectively; contrarily, diazepam was attractive, even at lethal concentrations, representing a dangerous trap for organisms. The toxicity of the PhACs seemed not to be directly related to their repellency; and the mode of action seems to determine the repellency or attractiveness of the chemicals. Contamination by PhACs is of concern due to the environmental disturbance they might cause, either due to their acute and chronic toxicity (at the individual level), repellency (at the ecosystem level: loss of local biodiversity) or attraction to potentially lethal levels. | This research was funded by: Coordination of Superior Level Staff Improvement (CAPES); National Council for Scientific and Technological Development (CNPq); Foundation for Research Support of the State of Minas Gerais (FAPEMIG) and the Federal University of Minas Gerais (UFMG). C.V.M. Araújo received the Ramón y Cajal contract (RYC-2017-22324) from the Spanish Ministry of Science and Innovation. | Peer reviewed
Show more [+] Less [-]Estimation of surface-level NO2 and O3 concentrations using TROPOMI data and machine learning over East Asia Full text
2021
Kang, Yoojin | Choi, Hyunyoung | Im, Jungho | Park, Seohui | Shin, Minso | Song, Chang-Keun | Kim, Sangmin
In East Asia, air quality has been recognized as an important public health problem. In particular, the surface concentrations of air pollutants are closely related to human life. This study aims to develop models for estimating high spatial resolution surface concentrations of NO₂ and O₃ from TROPOspheric Monitoring Instrument (TROPOMI) data in East Asia. The machine learning was adopted by fusion of various satellite-based variables, numerical model-based meteorological variables, and land-use variables. Four machine learning approaches—Support Vector Regression (SVR), Random Forest (RF), Extreme Gradient Boost (XGB), and Light Gradient Boosting Machine (LGBM)—were evaluated and compared with Multiple Linear Regression (MLR) as a base statistical method. This study also modeled the NO₂ and O₃ concentrations over the ocean surface (i.e., land model for scheme 1 and ocean model for scheme 2). The estimated surface concentrations were validated through three cross-validation approaches (i.e., random, temporal, and spatial). The results showed that the NO₂ model produced R² of 0.63–0.70 and normalized root-mean-square-error (nRMSE) of 38.3–42.2% and the O₃ model resulted in R² of 0.65–0.78 and nRMSE of 19.6–24.7% for scheme 1. The indirect validation based on the stations near the coastline for scheme 2 showed slight decrease (~0.3–2.4%) in nRMSE when compared to scheme 1. The contributions of input variables to the models were analyzed based on SHapely Additive exPlanations (SHAP) values. The NO₂ vertical column density among the TROPOMI-derived variables showed the largest contribution in both the NO₂ and O₃ models.
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