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Methods to assess bioavailability of hydrophobic organic contaminants: Principles, operations, and limitations
2013
Cui, Xinyi | Mayer, Philipp | Gan, Jay
Many important environmental contaminants are hydrophobic organic contaminants (HOCs), which include PCBs, PAHs, PBDEs, DDT and other chlorinated insecticides, among others. Owing to their strong hydrophobicity, HOCs have their final destination in soil or sediment, where their ecotoxicological effects are closely regulated by sorption and thus bioavailability. The last two decades have seen a dramatic increase in research efforts in developing and applying partitioning based methods and biomimetic extractions for measuring HOC bioavailability. However, the many variations of both analytical methods and associated measurement endpoints are often a source of confusion for users. In this review, we distinguish the most commonly used analytical approaches based on their measurement objectives, and illustrate their practical operational steps, strengths and limitations using simple flowcharts. This review may serve as guidance for new users on the selection and use of established methods, and a reference for experienced investigators to identify potential topics for further research.
Show more [+] Less [-]A sediment ecotoxicity assessment platform for in situ measures of chemistry, bioaccumulation and toxicity. Part 2: Integrated application to a shallow estuary
2012
Rosen, Gunther | Bart Chadwick, D. | Allen Burton, G. | Keith Taulbee, W. | Greenberg, Marc S. | Lotufo, Guilherme R. | Reible, Danny D.
A comprehensive, weight-of-evidence based ecological risk assessment approach integrating laboratory and in situ bioaccumulation and toxicity testing, passive sampler devices, hydrological characterization tools, continuous water quality sensing, and multi-phase chemical analyses was evaluated. The test site used to demonstrate the approach was a shallow estuarine wetland where groundwater seepage and elevated organic and inorganic contaminants were of potential concern. Although groundwater was discharging into the surficial sediments, little to no chemical contamination was associated with the infiltrating groundwater. Results from bulk chemistry analysis, toxicity testing, and bioaccumulation, however, suggested possible PAH toxicity at one station, which might have been enhanced by UV photoactivation, explaining the differences between in situ and laboratory amphipod survival. Concurrently deployed PAH bioaccumulation on solid-phase micro-extraction fibers positively correlated (r² ≥ 0.977) with in situ PAH bioaccumulation in amphipods, attesting to their utility as biomimetics, and contributing to the overall improved linkage between exposure and effects demonstrated by this approach.
Show more [+] Less [-]The sensitivity of the deepsea species northern shrimp (Pandalus borealis) and the cold-water coral (Lophelia pertusa) to oil-associated aromatic compounds, dispersant, and Alaskan North Slope crude oil
2020
Bytingsvik, Jenny | Parkerton, Thomas F. | Guyomarch, Julien | Tassara, Luca | LeFloch, Stephane | Arnold, W Ray | Brander, Susanne M. | Volety, Aswani | Camus, Lionel
This study investigated the sensitivity of two deepsea species using mortality of northern shrimp (Pandalus borealis) and polyp activity of stony coral (Lophelia pertusa) to dispersant, Corexit 9500 and aromatic hydrocarbons (toluene, 2-methylnaphthalene, phenanthrene) in 96-h tests. Resulting hydrocarbon toxicity data were fit to the Target Lipid Model to generate predictive models and determine species sensitivity. Toxicity of chemically enhanced water accommodated fractions of Alaskan North Slope crude oil (ANS-oil) was also investigated with shrimp using nominal loading, total petroleum hydrocarbons and biomimetic extraction (BE) as oil exposure metrics. Coral were more sensitive to dispersant than shrimp while similar sensitivity was observed for hydrocarbons. Study and literature findings indicate deepsea species exhibit acute sensitivities to dispersant, hydrocarbons and oil that are comparable to pelagic species. Results support use of passive sampling methods to quantify dissolved oil for interpreting oil toxicity tests and suggest models for predicting time-dependence of toxicity warrant re-evaluation.
Show more [+] Less [-]Ability of 3 extraction methods (BCR, Tessier and protease K) to estimate bioavailable metals in sediments from Huelva estuary (Southwestern Spain)
2016
Rosado, Daniel | Usero, José | Morillo, José
The bioavailable fraction of metals (Zn, Cu, Cd, Mn, Pb, Ni, Fe, and Cr) in sediments of the Huelva estuary and its littoral of influence has been estimated carrying out the most popular methods of sequential extraction (BCR and Tessier) and a biomimetic approach (protease K extraction). Results were compared to enrichment factors found in Arenicola marina. The linear correlation coefficients (R2) obtained between the fraction mobilized by the first step of the BCR sequential extraction, by the sum of the first and second steps of the Tessier sequential extraction, and by protease K, and enrichment factors in A. marina, are at their highest for protease K extraction (0.709), followed by BCR first step (0.507) and the sum of the first and second steps of Tessier (0.465). This observation suggests that protease K represents the bioavailable fraction more reliably than traditional methods (BCR and Tessier), which have a similar ability.
Show more [+] Less [-]Bioavailability of trace elements in surface sediments from Kongsfjorden, Svalbard
2013
Grotti, Marco | Soggia, Francesco | Ianni, Carmela | Magi, Emanuele | Udisti, Roberto
The bioavailability of trace elements in marine sediments from Kongsfjorden (Svalbard Islands, Norwegian Arctic) was assessed and discussed. Total concentrations of several elements were determined in two granulometric fractions and their bioavailability evaluated by both applying a sequential-selective extraction procedure and using a biomimetic approach based on proteolytic enzymes. Total concentration values and solid speciation patterns indicated overall that the anthropogenic impact of trace elements in the investigated area is negligible, although a minor enrichment with respect to crustal values was found for As, Cd, Cr, Ni, and V. Enrichment of trace elements in the <63-μm fraction compared to the coarser one was evident for As, Cd, Cr, and Ni. The evaluation of the bioavailable fractions showed that a large part of the total content of trace elements cannot enter the aquatic food chain and emphasised the risk of overestimating the environmental impact of heavy metals if the assessment is only based on total concentrations.
Show more [+] Less [-]Reviewing biomimicry design case studies as a solution to sustainable design
2022
Othmani, Nurul Izzati | Mohamed, Syahidah Amni | Abdul Hamid, Nor Hamizah | Ramlee, Noorliyana | Yeo, Lee Bak | Mohd Yunos, Mohd Yazid
There have been many studies on bio-inspired research, where biomimicry capabilities facilitating sustainable designs are in dearth. For a sustainable design, it is necessary to consider water efficiency, zero waste, thermal environment, and energy supply. This paper investigates how biomimicry is adopted in the sustainable design of buildings. A thorough content analysis of eight case studies focused on the built environment and how biomimicry integrated with the design of a building was executed. The selection of cases study was based on the concept of biomimicry by taking inspiration from nature and applying them in the everyday built environment. Thus, the building designs are more ecologically sustainable than conventional ones, where biomimicry approaches and principles are adopted. The findings suggest that the design of a building can inspire society with new ecological morals, where understanding of biological morphogenesis can inspire design to resolve challenges and essentially help create a healthy environment. Biomimicry harnesses and replicates the principles found in nature to create a built environment that benefits people and other living creatures and safeguards biodiversity. Thus, adopting biomimicry in designing a building will help to develop a culture of active environmental design.
Show more [+] Less [-]Degradation features of pesticides: a review on (metallo)porphyrin-mediated catalytic processes
2022
Martins, Dayse Carvalho da Silva | Resende, Iasmin Tavares | da Silva, Bruno José Rocha
Pesticides have been used to kill pests such as insects, fungi, rodents, and unwanted plants. Since these compounds are potentially toxic to the target organisms, they could also be harmful to human health and the environment. Several chronic adverse effects have been identified even after months or years of exposure. A few pesticide degradation processes have been studied including adsorption, homogeneous and heterogeneous (photo)catalytic oxidation, and biological methods. Although these methods have been playing a significant part in the pesticide’s degradation, there are still gaps in many aspects. Here, we review the catalytic degradation of these pollutants by (metallo)porphyrins. To evaluate the P450 cytochrome’s biomimetic behavior of these catalysts, various synthesized porphyrins have been used since 1999 and their activities were summarized in this manuscript. The porphyrins appear to act as good catalysts for the degradation of pesticides; in fact, they also have been shown as a useful tool for the elucidation of their degradation products. Achieving pesticide mineralization without intermediate products is still challenging, although the ability of this kind of catalysts to conduct the formation of some lower toxic products comparing their precursors has been verified.
Show more [+] Less [-]Robust bioinspired surfaces and their exploitation for petroleum hydrocarbon remediation
2022
Ali, Nisar | Gyllye, Essoh Lionnelle | Duanmu, Chuansong | Yang, Yong | Khan, Adnan | Ali, Farman | Vēlāyutan̲, T. A. | Iqbal, Hafiz M. N.
The current improvement in science and engineering, actively dealing with surfaces and interfaces, turns into a functioning control with a thriving advancement propensity. Superlyophobic/superlyophilic phenomena in surface sciences have pulled in broad considerations of researchers and specialists. Inspired by the natural and living organism, researchers have designed different biomimetic materials with exceptional surface wettability, such as the smart wetting of asymmetric spider silk surfaces. These smart materials with superlyophobic/superlyophilic wettability are generally utilized for water assortment, self-cleaning, fluid transportation and separation, and many researchers’ domains. Among them, emulsion separation, including division of oil-water blend, mixtures of immiscible liquids and oil-water emulsions, is highlighted by an increasing number of researchers. Numerous materials with one- and two-dimensional morphology, smart surfaces, and super wettability have been effectively designed and utilized in various scientific research applications. We expect that these bioinspired materials with super wettability can have promising applications in practical for emulsion destabilization and liquid transportation.
Show more [+] Less [-]Engineered topographies and hydrodynamics in relation to biofouling control—a review
2021
Halder, Partha | Hossain, Nazia | Pramanik, Biplob Kumar | Bhuiyan, Muhammed A
Biofouling, the unwanted growth of microorganisms on submerged surfaces, has appeared as a significant impediment for underwater structures, water vessels, and medical devices. For fixing the biofouling issue, modification of the submerged surface is being experimented as a non-toxic approach worldwide. This technique necessitated altering the surface topography and roughness and developing a surface with a nano- to micro-structured pattern. The main objective of this study is to review the recent advancements in surface modification and hydrodynamic analysis concerning biofouling control. This study described the occurrence of the biofouling process, techniques suitable for biofouling control, and current state of research advancements comprehensively. Different biofilms under various hydrodynamic conditions have also been outlined in this study. Scenarios of biomimetic surfaces and underwater super-hydrophobicity, locomotion of microorganisms, nano- and micro-hydrodynamics on various surfaces around microorganisms, and material stiffness were explained thoroughly. The review also documented the approaches to inhibit the initial settlement of microorganisms and prolong the subsequent biofilm formation process for patterned surfaces. Though it is well documented that biofouling can be controlled to various degrees with different nano- and micro-structured patterned surfaces, the understanding of the underlying mechanism is still imprecise. Therefore, this review strived to present the possibilities of implementing the patterned surfaces as a physical deterrent against the settlement of fouling organisms and developing an active microfluidic environment to inhibit the initial bacterial settlement process. In general, microtopography equivalent to that of bacterial cells influences attachment via hydrodynamics, topography-induced cell placement, and air-entrapment, whereas nanotopography influences physicochemical forces through macromolecular conditioning.
Show more [+] Less [-]Mechanisms and Applications of the Synthesized Fusiform Aragonite for the Removal of High Concentration of Phosphate
2016
Xu, Nan | Wang, Yunlong | Xu, Xiaoting | Liu, Cheng | Qian, Junchao | Feng, Gang
In the present work, the synthesized calcium carbonate (CaCO₃) identified as fusiform aragonite was obtained through the biomimetic mineralization process for possible recovery of high concentration of phosphorus (P) within the wide range of pH. It was characterized before/after phosphate sorption by the combination of X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray absorption near-edge structure (XANES) at molecular level. By batch experiments, the sorption isotherms and envelopes of the fusiform aragonite to phosphate were explored. The experimental data showed that the fusiform aragonite at pH ≥6.0 has a steep raising sorption capacity with increasing initial P (>9.0 mM) due to its unique crystalline structure and morphology. The likely mechanism is that the occurrence of fast nucleation growth of Ca-P phases (including amorphous calcium phosphate (ACP), dibasic calcium phosphate (DCP), and hydroxyapatite (HAP)) is triggered upon attainment of the stabilized crystal morphology of aragonite in solution due to phosphate sorption. These features may contribute to the fusiform aragonite as an idea adsorbent for high phosphate removal from wastewater even independent of pH.
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