1
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Dai D, Gu R, Qv M, Lv Y, Liu D, Tang C, Wang H, Huang L, Zhu L. Performance evaluation of typical flocculants for efficient harvesting of Chlorella sorokiniana under different carbon application modes. CHEMOSPHERE 2024; 361:142563. [PMID: 38851498 DOI: 10.1016/j.chemosphere.2024.142563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 05/29/2024] [Accepted: 06/06/2024] [Indexed: 06/10/2024]
Abstract
In this study, the growth characteristics of microalgae cultured with different carbon sources were analyzed, and the flocculation characteristics under the influence of carbon sources were evaluated using three typical flocculants. The results showed that the organic carbon sources could significantly increase the content of extracellular proteins in microalgae. Specifically, the extracellular protein concentrations of microalgae cultured with pure BG-11, ethanol, sodium acetate and glucose were 18.2 29.2, 97.3, and 34.7 mg/g, respectively. During the flocculation process, microalgae cultured with sodium acetate exhibited a weak response to the flocculant because of excessive extracellular proteins inhibited flocculation. In addition, the flocculation efficiency was also less than 50.0% cultured with sodium acetate in all pH test ranges when alum and chitosan were used as flocculants. It could be inferred that the flocculant initially happened to charge neutralization with the negatively charged proteins in the solution and then bridged the charges with the microalgae. These findings provide insights into the effects of different carbon sources on microalgal flocculation, promising organic integration of microalgae wastewater treatment and harvesting.
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Affiliation(s)
- Dian Dai
- School of Resource and Environmental Sciences, Hubei Key Laboratory of Biomass-Resources Chemistry and Environmental Biotechnology, and Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Wuhan University, Wuhan 430079, China
| | - Ruoting Gu
- School of Resource and Environmental Sciences, Hubei Key Laboratory of Biomass-Resources Chemistry and Environmental Biotechnology, and Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Wuhan University, Wuhan 430079, China
| | - Mingxiang Qv
- School of Resource and Environmental Sciences, Hubei Key Laboratory of Biomass-Resources Chemistry and Environmental Biotechnology, and Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Wuhan University, Wuhan 430079, China
| | - Yuanfei Lv
- School of Resource and Environmental Sciences, Hubei Key Laboratory of Biomass-Resources Chemistry and Environmental Biotechnology, and Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Wuhan University, Wuhan 430079, China
| | - Dongyang Liu
- School of Resource and Environmental Sciences, Hubei Key Laboratory of Biomass-Resources Chemistry and Environmental Biotechnology, and Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Wuhan University, Wuhan 430079, China
| | - Chunming Tang
- School of Resource and Environmental Sciences, Hubei Key Laboratory of Biomass-Resources Chemistry and Environmental Biotechnology, and Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Wuhan University, Wuhan 430079, China
| | - Hanzhi Wang
- School of Resource and Environmental Sciences, Hubei Key Laboratory of Biomass-Resources Chemistry and Environmental Biotechnology, and Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Wuhan University, Wuhan 430079, China
| | - Lizhi Huang
- School of Civil Engineering, Wuhan University, Wuhan 430072, China
| | - Liandong Zhu
- School of Resource and Environmental Sciences, Hubei Key Laboratory of Biomass-Resources Chemistry and Environmental Biotechnology, and Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Wuhan University, Wuhan 430079, China; State Key Laboratory of Water Resources Engineering and Management, Wuhan University, Wuhan, Hubei, 430072, China.
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2
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Zhang Q, Shi H, Zhao Y, Pu J, Peng C, Wu R, Zhang Y, Xu Z, Wang T. Effects of chitosan and rice husk powder on thermal hydrolysis-anaerobic digested sludge conditioning: Dewaterability and biogas slurry fertility. CHEMOSPHERE 2024; 351:141267. [PMID: 38246498 DOI: 10.1016/j.chemosphere.2024.141267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 12/18/2023] [Accepted: 01/18/2024] [Indexed: 01/23/2024]
Abstract
To enhance the dewaterability of anaerobic digested sludge and to make full use of the biogas slurry. This study set up five sludge conditioning methods: polymeric ferric sulfate, polymeric aluminum chloride, cationic polyacrylamide, chitosan, and chitosan combined with rice husk powder. Their effects on the dewaterability of thermal hydrolysis-anaerobic digested sludge, bacterial community, and biogas slurry fertility were studied to find a non-toxic and non-risk dewatering technology for the environment and biogas slurry. Compared with that of the control group, moisture content, normalization capillary suction time, and specific resistance to filtration were reduced by 12.8%, 97.7%, and 82.9%, respectively. Chitosan enlarges the sludge flocs and forms complexes with proteins, disrupting the structure of the extracellular polymeric substances, thereby exposing more hydrophobic groups and reducing the hydrophilicity of the sludge. The subsequent addition of rice husk powder enhances the adsorption of hydrophilic substances and provides a stronger drainage channel for the sludge. In addition, the biogas slurry obtained by this conditioning method used as a fertilizer increased the dry weight and fresh weight of corn seedlings by 59.3% and 91.0%, respectively. And the total chlorophyll content increased by 84.6%. Pearson's correlation analysis showed that chitosan and rice husk meal had no toxic effect on the biogas slurry compared to the other three flocculants. The results showed that the combined treatment of chitosan and rice husk powder resulted in the best dewaterability. Overall, chitosan combined with rice husk powder is a green dewatering technology with great potential for anaerobic digested sludge dewatering and biogas slurry recycling.
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Affiliation(s)
- Qingfang Zhang
- College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, 730050, China
| | - Hailong Shi
- College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, 730050, China
| | - Yanbin Zhao
- College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, 730050, China
| | - Jiajia Pu
- College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, 730050, China
| | - Cheng Peng
- College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, 730050, China
| | - Ruoyu Wu
- College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, 730050, China
| | - Yuqian Zhang
- College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, 730050, China
| | - Ziying Xu
- College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, 730050, China
| | - Tianfeng Wang
- College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, 730050, China.
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3
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Hansen AMB, Brill JL, Connors KA, Belanger SE, Baun A, Sanderson H. Understanding ecotoxicological drivers and responses of freshwater green algae, Raphidocelis subcapitata, to cationic polyquaternium polymers. ENVIRONMENTAL RESEARCH 2023; 231:116282. [PMID: 37257746 DOI: 10.1016/j.envres.2023.116282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 05/12/2023] [Accepted: 05/28/2023] [Indexed: 06/02/2023]
Abstract
Cationic polymer (CP) ecotoxicity is important to understand and investigate as they are widely used in industrial and consumer applications and have shown toxic effects in some aquatic organisms. CPs are identified as "polymers of concern" and are to be prioritized in upcoming regulatory reviews, (e.g., REACH). Algae have generally been found to be the most sensitive trophic level to CP. This study aimed at elucidating the magnitude of cationic polyquaternium toxicity towards algae and to understand key toxicological drivers. A suite of polyquaterniums with varying charge density (charged nitrogen moieties) and molecular weight were selected. Highly charged polyquaternium-6 and -16 were toxic towards the freshwater green microalgae Raphidocelis subcapitata with ErC50-values ranging between 0.12 and 0.41 mg/L. Lower charge density polyquaternium-10 materials had much lower toxicity with ErC50 > 200 mg/L, suggesting that charge density is an important driver of algal toxicity. These levels of toxicity were in line with historic CP data in literature. Algal agglomeration was observed in all tests but was not linked with impacts on algal growth rate. However, agglomeration can pose challenges in the technical conduct of tests and can impair interpretation of results. The toxicity mitigation potential of humic acid was also explored. The addition of 2-20 mg/L humic acid completely mitigated PQ6 and PQ16 toxicity at concentrations higher than clean water ErC50-values. CP toxicity mitigation has also been observed in fish and invertebrate tests, suggesting that CP mitigation should be accounted for in all trophic levels within an environmental safety framework.
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Affiliation(s)
| | - Jessica L Brill
- Environmental Stewardship and Sustainability, The Procter & Gamble Company, Mason, OH, USA
| | - Kristin A Connors
- Environmental Stewardship and Sustainability, The Procter & Gamble Company, Mason, OH, USA.
| | - Scott E Belanger
- Environmental Stewardship and Sustainability, The Procter & Gamble Company, Mason, OH, USA
| | - Anders Baun
- Department of Environmental and Resource Engineering, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Hans Sanderson
- Department of Environmental Science, Aarhus University, Roskilde, Denmark
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4
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Connors KA, Arndt D, Rawlings JM, Brun Hansen AM, Lam MW, Sanderson H, Belanger SE. Environmental hazard of cationic polymers relevant in personal and consumer care products: A critical review. INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT 2023; 19:312-325. [PMID: 35649733 DOI: 10.1002/ieam.4642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 05/13/2022] [Accepted: 05/27/2022] [Indexed: 06/15/2023]
Abstract
Historically, polymers have been excluded from registration and evaluation under the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) program, the European chemical management program. Recently, interest has increased to include polymers. A tiered registration system has been envisioned and would begin with classes of polymers of greater interest based on certain properties. Cationic polymers are one such class. There is a pressing need to understand the quality and limitations of historical cationic polymer studies and to identify key sources of uncertainty in environmental hazard assessments so we can move toward scientifically robust analyses. To that end, we performed a critical review of the existing cationic polymer environmental effects literature to evaluate polymer characterization and test methodologies to understand how these parameters may affect test interpretation. The relationship between physicochemical parameters, acute and chronic toxicity, and relative trophic level sensitivity were explored. To advance our understanding of the environmental hazard and subsequent risk characterization of cationic polymers, there is a clear need for a consistent testing approach as many polymers are characterized as difficult-to-test substances. Experimental parameters such as dissolved organic carbon and solution renewal approaches can alter cationic polymer bioavailability and toxicity. It is recommended that OECD TG 23 "Aqueous-Phase Aquatic Toxicity Testing of Difficult Test Substances" testing considerations be applied when conducting environmental toxicity assays with cationic polymers. Integr Environ Assess Manag 2023;19:312-325. © 2021 SETAC.
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Affiliation(s)
| | - Devrah Arndt
- The Procter and Gamble Company, Cincinnati, OH, USA
| | | | | | - Monica W Lam
- The Procter and Gamble Company, Cincinnati, OH, USA
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5
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Tavares J, Venâncio C, Duarte C, Antunes FE, Lopes I. Adding knowledge to the design of safer hydrophobically modified poly(acrylic) acids: an ecotoxicological approach. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:39258-39271. [PMID: 36598726 PMCID: PMC9812012 DOI: 10.1007/s11356-022-24963-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 12/20/2022] [Indexed: 06/17/2023]
Abstract
The architecture of hydrophobically modified polymers can be tailored to produce variants with different levels of functionality. This allows industry to apply rational design methods for the development of more environmentally friendly materials. In the present work, the ecotoxicity of six variants of hydrophobically modified poly(acrylic) acids (HMPAA), obtained by changing the crosslinked conformation, insertion position, and length of the hydrophobic groups, was assessed for the (i) bioluminescence production of Aliivibrio fischeri; (ii) population growth rate of Raphidocelis subcapitata and Chlorella vulgaris; (iii) mortality of Brachionus calyciflorus; (iv) feeding inhibition, somatic growth rate, reproduction, and mortality of Daphnia magna; and (iv) mortality and somatic growth rate of Pelophylax perezi tadpoles. The concentrations causing 50% and 20% of effects (L(E)C50 and 20, respectively) ranged from 9.64 up to > 2000 mg·L-1 for all six HMPAA and species. The bacterium A. fischeri and tadpoles of P. perezi were the most sensitive and most tolerant organisms to the six tested HMPAA, respectively. The computed 5% hazard concentrations (computed on the basis of L(E)C50 s) showed that HMPAA1 (13.0 mg·L-1) and HMPAA2 (26.1 mg·L-1) were the most toxic variants, while HMPAA6 (233 mg·L-1) the least one. These results suggest HMPAA6 (with low crosslink percentage modified by the addition of long and short hydrophobic groups at the surface) to be the most environmentally friendly variant and should be preferentially considered to be used in consumer products, compared to the other five studied variants.
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Affiliation(s)
- Jorge Tavares
- Department of Biology, University of Aveiro, Campus de Santiago, P-3810-193, Aveiro, Portugal
| | - Cátia Venâncio
- Department of Biology, University of Aveiro, Campus de Santiago, P-3810-193, Aveiro, Portugal
- CESAM - Centre for Environmental and Marine Studies, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Cláudia Duarte
- Department of Chemistry, University of Coimbra, Coimbra, Portugal
| | - Filipe E Antunes
- Department of Chemistry, University of Coimbra, Coimbra, Portugal
| | - Isabel Lopes
- Department of Biology, University of Aveiro, Campus de Santiago, P-3810-193, Aveiro, Portugal.
- CESAM - Centre for Environmental and Marine Studies, University of Aveiro, 3810-193, Aveiro, Portugal.
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6
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Mehmood T, Mustafa B, Mackenzie K, Ali W, Sabir RI, Anum W, Gaurav GK, Riaz U, Liu X, Peng L. Recent developments in microplastic contaminated water treatment: Progress and prospects of carbon-based two-dimensional materials for membranes separation. CHEMOSPHERE 2023; 316:137704. [PMID: 36592840 DOI: 10.1016/j.chemosphere.2022.137704] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Revised: 12/23/2022] [Accepted: 12/29/2022] [Indexed: 06/17/2023]
Abstract
Micro (nano)plastics pollution is a noxious menace not only for mankind but also for marine life, as removing microplastics (MPs) is challenging due to their physiochemical properties, composition, and response toward salinity and pH. This review provides a detailed assessment of the MPs pollution in different water types, environmental implications, and corresponding treatment strategies. With the advancement in nanotechnology, mitigation strategies for aqueous pollution are seen, especially due to the fabrication of nanosheets/membranes mostly utilized as a filtration process. Two-dimensional (2D) materials are increasingly used for membranes due to their diverse structure, affinity, cost-effectiveness, and, most importantly, removal efficiency. The popular 2D materials used for membrane-based organic and inorganic pollutants from water mainly include graphene and MXenes however their effectiveness for MPs removal is still in its infancy. Albeit, the available literature asserts a 70- 99% success rate in micro/nano plastics removal achieved through membranes fabricated via graphene oxide (GO), reduced graphene oxide (rGO) and MXene membranes. This review examined existing membrane separation strategies for MPs removal, focusing on the structural properties of 2D materials, composite, and how they adsorb pollutants and underlying physicochemical mechanisms. Since MPs and other contaminants commonly coexist in the natural environment, a brief examination of the response of 2D membranes to MPs removal was also conducted. In addition, the influencing factors regulate MPs removal performance of membranes by impacting their two main operating routes (filtration and adsorption). Finally, significant limitations, research gaps, and future prospects of 2D material-based membranes for effectively removing MPs are also proposed. The conclusion is that the success of 2D material is strongly linked to the types, size of MPs, and characteristics of aqueous media. Future perspectives talk about the problems that need to be solved to get 2D material-based membranes out of the lab and onto the market.
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Affiliation(s)
- Tariq Mehmood
- College of Ecology and Environment, Hainan University, Haikou, Hainan Province, 570228, China; Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Engineering, Permoserstr. 15, D-04318 Leipzig, Germany.
| | - Beenish Mustafa
- National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing 210093, China
| | - Katrin Mackenzie
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Engineering, Permoserstr. 15, D-04318 Leipzig, Germany
| | - Wahid Ali
- Department of Chemical Engineering Technology, College of Applied Industrial Technology (CAIT), Jazan University, Kingdom of Saudi Arabia
| | - Raja Irfan Sabir
- Faculty of Management Sciences, University of Central Punjab, Lahore; Pakistan
| | - Wajiha Anum
- Regional Agricultural Research Institute, Bahawalpur, Pakistan
| | - Gajendra Kumar Gaurav
- Sustainable Process Integration Laboratory, SPIL, NETME Centre, Faculty of Mechanical Engineering, Brno University of Technology, VUT Brno, Technická 2896/2, 616 69, Brno, Czech Republic; School of Physics and Electronic Information, Yan'an University, Yan'an, 716000, China
| | - Umair Riaz
- Department of Soil and Environmental Sciences, Muhammad Nawaz Shareef University of Agriculture, Multan, 60000, Pakistan
| | - Xinghui Liu
- School of Physics and Electronic Information, Yan'an University, Yan'an, 716000, China; Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong, 999077 China
| | - Licheng Peng
- College of Ecology and Environment, Hainan University, Haikou, Hainan Province, 570228, China; Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, Hainan University, Haikou, Hainan Province, 570228, China.
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7
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Yakimenko O, Ziganshina A, Terekhova V, Panova I, Gladkova M, Timofeev M, Yaroslavov A. Ecotoxicity of polyelectrolyte formulations in water and soil matrices. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:65489-65499. [PMID: 35488153 DOI: 10.1007/s11356-022-20449-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 04/21/2022] [Indexed: 06/14/2023]
Abstract
Interpolyelectrolyte complexes (IPECs) formed by the interaction of two oppositely charged polyelectrolytes have been proposed as soil structure stabilizers. However, little is known about the environmental safety of IPECs. The goal of this study was to investigate the toxicity of a positively charged IPEC formed by two commercial polymers, namely the cationic biopolymer poly(diallyldimethylammonium chloride) (PDDA) and the anionic biopolymer lignohumate (LH), a humic-based plant growth promoter. Toxicity was assessed using cultures of the bacteria Escherichia coli, the ciliate Paramecium caudatum, mammalian (Bos taurus) spermatozoa in vitro, and three plant species (Sinapis alba, Raphanus sativus, and Triticum durum). The responses of test organisms were evaluated in contact with (1) polymer and water and (2) polymer and soil. In water, PDDA and IPEC were highly toxic to bacteria and ciliates at all concentrations and less toxic to mammalian cells. Higher plants were less sensitive to the polymers, and the toxicity progressively decreased in the order PDDA > IPEC > LH. In soil matrices; the phytotoxicity of PDDA and IPEC was found to be quite low, and none of the polymers was toxic to plants at concentrations that allowed the formation of polymeric soil crusts against erosion. This is because the toxicity of cationic polymers decreases as they enter the soil matrix and bind to organic matter and minerals.
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Affiliation(s)
- Olga Yakimenko
- Department of Soil Science, Lomonosov Moscow State University, Leninskie Gory 1-12, Moscow, 119991, Russian Federation.
| | - Aliya Ziganshina
- Department of Soil Science, Lomonosov Moscow State University, Leninskie Gory 1-12, Moscow, 119991, Russian Federation
| | - Vera Terekhova
- Department of Soil Science, Lomonosov Moscow State University, Leninskie Gory 1-12, Moscow, 119991, Russian Federation
- A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences, Leninsky Prospekt 33, Moscow, 119071, Russian Federation
| | - Irina Panova
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1-3, Moscow, 119991, Russian Federation
| | - Marina Gladkova
- Department of Soil Science, Lomonosov Moscow State University, Leninskie Gory 1-12, Moscow, 119991, Russian Federation
| | - Mikhail Timofeev
- Department of Soil Science, Lomonosov Moscow State University, Leninskie Gory 1-12, Moscow, 119991, Russian Federation
| | - Alexander Yaroslavov
- Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1-3, Moscow, 119991, Russian Federation
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8
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Rawlings JM, Belanger SE, Connors KA, Karb MJ, Thomas JB, Roush KS, Sanderson H. Understanding Ecotoxicological Responses of Fish Embryos and Gill Cells to Cationic Polymers. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2022; 41:2259-2272. [PMID: 35703088 DOI: 10.1002/etc.5410] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 04/18/2022] [Accepted: 06/14/2022] [Indexed: 06/15/2023]
Abstract
Cationic polymers are considered by the scientific and regulatory communities as a group of greater interest amongst the polymers in commerce. As a category, relatively little hazard information is available in the public literature. Very few examples exist of published, high-quality polymer characterization and quantification of exposure. In the present study we describe a series of fish embryo toxicity (FET) and fish gill cytotoxicity assays used to establish a baseline understanding of several representative polyquaternium categories (PQ-6, PQ-10, PQ-16) in animal alternative models, accompanied by high-quality analytical characterization. Materials were chosen to encompass a range of molecular weights and charge densities to determine the influence of test material characteristics on toxicity. Both chorionated and dechorionated FET assays were generally similar to published acute fish toxicity data. Toxicity was correlated with cationic polymer charge density, and not with molecular weight, and was a combination of physical effects and likely toxicity at the site of action. Toxicity could be ameliorated by humic acid in a dose-dependent manner. Fish gill cytotoxicity results were orders of magnitude less sensitive than FET test responses. Environ Toxicol Chem 2022;41:2259-2272. © 2022 SETAC.
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Affiliation(s)
- Jane M Rawlings
- Global Product Stewardship, Environmental Stewardship and Sustainability, The Procter & Gamble Company, Cincinnati, Ohio, USA
| | - Scott E Belanger
- Global Product Stewardship, Environmental Stewardship and Sustainability, The Procter & Gamble Company, Cincinnati, Ohio, USA
| | - Kristin A Connors
- Global Product Stewardship, Environmental Stewardship and Sustainability, The Procter & Gamble Company, Cincinnati, Ohio, USA
| | - Mike J Karb
- Corporate Functions Analytical, The Procter & Gamble Company, Cincinnati, Ohio, USA
| | - Jacqueline B Thomas
- Corporate Functions Analytical, The Procter & Gamble Company, Cincinnati, Ohio, USA
| | - Kyle S Roush
- Global Product Stewardship, Environmental Stewardship and Sustainability, The Procter & Gamble Company, Cincinnati, Ohio, USA
| | - Hans Sanderson
- Department of Environmental Science, Section for Toxicology and Chemistry, Aarhus University, Roskilde, Denmark
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9
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Magalhães S, Moreira A, Almeida R, Cruz PF, Alves L, Costa C, Mendes C, Medronho B, Romano A, Carvalho MDG, Gamelas JAF, Rasteiro MDG. Acacia Wood Fractionation Using Deep Eutectic Solvents: Extraction, Recovery, and Characterization of the Different Fractions. ACS OMEGA 2022; 7:26005-26014. [PMID: 35936445 PMCID: PMC9352220 DOI: 10.1021/acsomega.1c07380] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The selective extraction and recovery of different lignocellulosic molecules of interest from forestry residues is increasing every day not only to satisfy the needs of driving a society toward more sustainable approaches and materials (rethinking waste as a valuable resource) but also because lignocellulosic molecules have several applications. For this purpose, the development of new sustainable and ecologically benign extraction approaches has grown significantly. Deep eutectic solvents (DESs) appear as a promising alternative for the processing and manipulation of biomass. In the present study, a DES formed using choline chloride and levulinic acid (ChCl:LA) was studied to fractionate lignocellulosic residues of acacia wood (Acacia dealbata Link), an invasive species in Portugal. Different parameters, such as temperature and extraction time, were optimized to enhance the yield and purity of recovered cellulose and lignin fractions. DESs containing LA were found to be promising solvent systems, as the hydrogen bond donor was considered relevant in relation to lignin extraction and cellulose concentration. On the other hand, the increase in temperature and extraction time increases the amount of extracted material from biomass but affects the purity of lignin. The most promising DES system, ChCl:LA in a ratio of 1:3, was found to not significantly depolymerize the extracted lignin, which presented a similar molecular weight to a kraft lignin. Additionally, the 31P NMR results revealed that the extracted lignin has a high content of phenolic OH groups, which favor its reactivity. A mixture of ChCl:LA may be considered a fully renewable solvent, and the formed DES presents good potential to fractionate wood residues.
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Affiliation(s)
- Solange Magalhães
- CIEPQPF,
Department of Chemical Engineering, University
of Coimbra, Pólo II − R. Silvio Lima, 3030-790 Coimbra, Portugal
| | - Adriana Moreira
- CIEPQPF,
Department of Chemical Engineering, University
of Coimbra, Pólo II − R. Silvio Lima, 3030-790 Coimbra, Portugal
| | - Ricardo Almeida
- CIEPQPF,
Department of Chemical Engineering, University
of Coimbra, Pólo II − R. Silvio Lima, 3030-790 Coimbra, Portugal
| | - Pedro Fernandes Cruz
- CQC,
Department of Chemistry, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal
| | - Luís Alves
- CIEPQPF,
Department of Chemical Engineering, University
of Coimbra, Pólo II − R. Silvio Lima, 3030-790 Coimbra, Portugal
| | - Carolina Costa
- FSCN,
Surface and Colloid Engineering, Mid Sweden
University, SE-851 70 Sundsvall, Sweden
| | - Cátia Mendes
- CIEPQPF,
Department of Chemical Engineering, University
of Coimbra, Pólo II − R. Silvio Lima, 3030-790 Coimbra, Portugal
| | - Bruno Medronho
- FSCN,
Surface and Colloid Engineering, Mid Sweden
University, SE-851 70 Sundsvall, Sweden
- MED
− Mediterranean Institute for Agriculture, Environment and
Development, Universidade do Algarve, Faculdade
de Ciênicas e Tecnologias, Campus de Gambelas, Ed. 8, 8005-139 Faro, Portugal
| | - Anabela Romano
- MED
− Mediterranean Institute for Agriculture, Environment and
Development, Universidade do Algarve, Faculdade
de Ciênicas e Tecnologias, Campus de Gambelas, Ed. 8, 8005-139 Faro, Portugal
| | - Maria da Graça Carvalho
- CIEPQPF,
Department of Chemical Engineering, University
of Coimbra, Pólo II − R. Silvio Lima, 3030-790 Coimbra, Portugal
| | - José A. F. Gamelas
- CIEPQPF,
Department of Chemical Engineering, University
of Coimbra, Pólo II − R. Silvio Lima, 3030-790 Coimbra, Portugal
| | - Maria da Graça Rasteiro
- CIEPQPF,
Department of Chemical Engineering, University
of Coimbra, Pólo II − R. Silvio Lima, 3030-790 Coimbra, Portugal
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10
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Ren B, Weitzel KA, Duan X, Nadagouda MN, Dionysiou DD. A comprehensive review on algae removal and control by coagulation-based processes: mechanism, material, and application. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.121106] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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11
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Sturm MT, Schuhen K, Horn H. Method for rapid biofilm cultivation on microplastics and investigation of its effect on the agglomeration and removal of microplastics using organosilanes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:151388. [PMID: 34740650 DOI: 10.1016/j.scitotenv.2021.151388] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/26/2021] [Accepted: 10/29/2021] [Indexed: 06/13/2023]
Abstract
Since microplastics were recognized as a global environmental problem in the early 2000s, research began on possible solutions such as the removal of microplastics from waters. A novel and promising approach for this purpose is microplastics agglomeration-fixation using organosilanes. In this study, it is investigated how biofilm coverage of microplastics affects this process. The biofilm was grown on the microplastics by cultivating it for one week in a packed bed column operated with biologically treated municipal wastewater enriched with glucose. The biofilm was characterized using confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), and Fourier-Transform infrared spectroscopy (FT-IR). The results show a partial coverage of the microplastics with attached bacteria and extracellular polymeric substances (EPS) after 7 days of incubation. Comparing five polymer types (polyethylene, polypropylene, polyamide, polyester, and polyvinyl chloride) and three organosilanes, the biofilm coverage caused a reduced removal efficiency for all combinations tested as it changes the surface chemistry of the microplastics and therefore the interaction with the organosilanes tested in this study. Treatment of biofilm covered microplastic with ultrasound partly recovers the removal. However, the results underline the importance of simulated environmental exposure when performing experiments for microplastic removal.
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Affiliation(s)
- Michael T Sturm
- Wasser 3.0 gGmbH, Neufeldstr. 17a-19a, 71687 Karlsruhe, Germany; abcr GmbH, Im Schlehert 10, 76187 Karlsruhe, Germany; Karlsruhe Institute of Technology (KIT), Engler-Bunte-Institut (EBI), Chair of Water Chemistry and Water Technology, Engler-Bunte-Ring 9a, 76131 Karlsruhe, Germany
| | - Katrin Schuhen
- Wasser 3.0 gGmbH, Neufeldstr. 17a-19a, 71687 Karlsruhe, Germany
| | - Harald Horn
- Karlsruhe Institute of Technology (KIT), Engler-Bunte-Institut (EBI), Chair of Water Chemistry and Water Technology, Engler-Bunte-Ring 9a, 76131 Karlsruhe, Germany; DVGW Research Laboratories, Water Chemistry and Water Technology, Engler-Bunte-Ring 9a, 76131 Karlsruhe, Germany.
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12
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Quantitative analyses to estimate the bioaccessibility of a hydrolytically degradable cationic flocculant. Heliyon 2021; 7:e08500. [PMID: 34926853 PMCID: PMC8646992 DOI: 10.1016/j.heliyon.2021.e08500] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 09/14/2021] [Accepted: 11/25/2021] [Indexed: 11/23/2022] Open
Abstract
Poly(lactic acid) choline iodide ester methacrylate, poly(PLA4ChMA), is a cationic degradable polymer that can flocculate particles and dewater oil sands from tailings ponds. This novel material has yet to be characterized in terms of environmental and human health. If ingested, this substance may become bioaccessible. The bioaccessibility (bioaccessible fraction) of an ingested contaminant is a measure of the portion of an ingested dose that solubilizes and may be available for systemic absorption. In the present study, the partially degraded flocculant and its degradation products, modelled using lactic acid and choline chloride, were subjected to a modified physiologically based extraction test (PBET). Bioaccessible fractions were estimated by proton nuclear magnetic resonance (1H-NMR) spectroscopy and by high-performance liquid chromatography (HPLC). The measured bioaccessibility of lactic acid in gastric solution containing choline chloride is ∼100% but slightly dropped to 94% in intestinal solution at a solid-to-liquid ratio of 1:200. The partially degraded poly(PLA4ChMA) did not degrade further during the PBET and is not solubilized (i.e., 0% bioaccessibility) in the gastric phase but is fully solubilized (i.e., 100% bioaccessibility) in the intestinal phase. At the end of PBET intestinal digestion, the molar ratio of lactic acid to choline chloride in the presence of degraded poly(PLA4ChMA) was 2, approximately the same as in the initial solution. Thus, lactic acid and choline chloride are solubilized to the same extents in both gastric and intestinal solutions. Results suggest that HPLC can be used to directly estimate the bioaccessibility of lactic acid, whereas 1H - NMR may be used to indirectly quantify the bioaccessibility of both lactic acid and choline chloride by determining their molar ratio in PBET extracts. In future works, these findings may be applied to the estimation of risks from exposure to poly(PLA4ChMA) as well as to the remediation of contaminants flocculated by poly(PLA4ChMA) in tailings ponds and in other wastewaters. 1H-NMR combined with HPLC are used to quantify poly(PLA4ChMA) bioaccessibility. Poly(PLA4ChMA) is 100% bioaccessible in intestinal but not in gastric fluids. Degradation products lactic acid and choline chloride are solubilized in GI tract. Molar ratio of lactic acid to choline chloride remains constant throughout GI tract. Degraded poly(PLA4ChMA) does not degrade further in simulated human GI tract.
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13
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Simões AM, Venâncio C, Alves L, Antunes FE, Lopes I. Hydrophobic modifications of hydroxyethyl cellulose polymers: Their influence on the acute toxicity to aquatic biota. JOURNAL OF HAZARDOUS MATERIALS 2021; 409:124966. [PMID: 33418294 DOI: 10.1016/j.jhazmat.2020.124966] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 12/18/2020] [Accepted: 12/23/2020] [Indexed: 06/12/2023]
Abstract
The hydrophobic substitution (HS) of cationic cellulose derivatives may be tuned, promoting their efficiency. This work studied the influence of HS on the acute ecotoxicity of quaternized hydroxyethyl cellulose polymers (SL) to aquatic biota. The ecotoxicity of four SL with different HS (SL-5, SL-30, SL-60, SL-100) was assessed for seven species: Vibrio fischeri, Raphidocelis subcapitata, Chlorella vulgaris, Daphnia magna, Brachionus calyciflorus, Heterocypris incongruens, and Danio rerio. The computed median effective concentrations were used to derive hazard concentrations, by using species sensitive distribution curves. All SL suspensions were characterized for particle size, zeta potential and rheological properties. Results indicated instability of the SL in suspension due to their relatively low zeta potential. Raphidocelis subcapitata, C. vulgaris and B. calyciflorus were the most sensitive to the four SL, suggesting that exposure to these compounds may imbalance the lowest trophic levels. Also, HS influenced the toxicity of SL, with the lowest HS (SL-5) revealing lower ecotoxicity. The maximum acceptable concentrations were 14.0, 2.9, 3.9 and 1.4 mg L-1 for SL-5, SL-30, SL-60, and SL-100, respectively. Accordingly, SL-5 is suggested as the eco-friendliest and is recommended to be used in the production of care products, in detriment of the other three tested variants.
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Affiliation(s)
- Anabela M Simões
- CESAM & Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal; CQC, Department of Chemistry, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal
| | - C Venâncio
- University of Coimbra, Centre for Functional Ecology, Department of Life Sciences, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal
| | - Luís Alves
- University of Coimbra, CIEPQPF, Department of Chemical Engineering, Rua Sílvio Lima, Pólo II, PT, 3030-790 Coimbra, Portugal
| | - Filipe E Antunes
- CQC, Department of Chemistry, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal
| | - Isabel Lopes
- CESAM & Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal.
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14
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Removal of Microplastics from Waters through Agglomeration-Fixation Using Organosilanes—Effects of Polymer Types, Water Composition and Temperature. WATER 2021. [DOI: 10.3390/w13050675] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Due to the fact, that microplastics are a global environmental problem, new ways for their removal from water, soil and air need to be developed. New materials in combination with easy to implement technologies for microplastic removal come into the focus of scientific studies and engineering, especially for application in water resources. In our comparative case study, the effects of water composition and temperature on the agglomeration-fixation reaction of microplastics using organosilanes were examined. We compared biologically treated municipal wastewater, seawater and demineralized water at temperatures ranging from 7.5–40 °C. Temperature variations and tested water compositions showed no negative effect on microplastic removal. The residues of the organosilanes remaining in the water after the fixation process were monitored using ICP-OES and DOC measurements. Only one of the organosilanes tested showed no dissolved residues in the waters. Microplastic encompasses a multitude of different types of polymers with different properties and surface chemistries. Therefore, we compared the efficiency of the process for polyethylene, polypropylene, polyamide, polyester, and polyvinylchloride as examples of common polymer types with different chemical compositions. A strong effect of the polarity of microplastics and organosilanes on removal efficiency was observed. The organic groups of organosilanes can be chemically adapted to different polymer types.
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15
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Salinas ER, Bozich JS, Kolbenschlag S, Kary-Heinrich M, Hopp PW, Lukas R, Zok S, Hidding B. Aquatic testing guidelines insufficiently control the influence of dilution water toc and hardness on cationic polymer toxicity - A proposal to improve standardized test procedures. CHEMOSPHERE 2020; 259:127473. [PMID: 32622247 DOI: 10.1016/j.chemosphere.2020.127473] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/10/2020] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
Cationic polymers (CPs) are widely used chemicals for wastewater treatment applications and in various "down-the-drain" household products. The aquatic toxicity of CPs results from an electrostatic interaction with negatively charged cell surfaces. These effects are greatly mitigated by the binding affinity of CPs to total organic carbon (TOC) in surface water. Consequently, baseline aquatic toxicity tests of CPs using clean lab water (TOC < 2 mg/L) typically overestimate toxicity and risk which is greatly mitigated at higher environmentally relevant OC levels. However, the point at which mitigation begins is not well defined and low-level TOC in lab water may influence the baseline toxicity outcome. Similarly, divalent cations, quantified as water hardness, may modulate the electrostatic binding between OC and CP. Although standard guidelines define limits for lab water hardness and TOC, the consequences of variability within those limits on test outcome is unknown. We investigated the impact of part-per-billion (ppb) additions of TOC to lab water at different hardness levels on CP acute toxicity to Daphnia magna and Raphidocelis subcapitata. In both species, the acute toxicities of CPs with different molecular weight and charge density varied by > 10-fold in response to slight changes in TOC and water hardness, although parameters were maintained within guideline limits. When determining the baseline aquatic toxicity of CPs, the lab water should be standardized at the lowest biologically tolerable hardness and TOC at a reliably measurable level (>1 - < 2 mg/L) to reduce variability and increase the reliability of the toxicity estimate.
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Affiliation(s)
- Edward R Salinas
- Experimental Ecotoxicology, BASF SE, Carl-Bosch-Strasse 38, 67056, Ludwigshafen, Germany.
| | - Jared S Bozich
- Experimental Ecotoxicology, BASF SE, Carl-Bosch-Strasse 38, 67056, Ludwigshafen, Germany
| | - Sara Kolbenschlag
- Experimental Ecotoxicology, BASF SE, Carl-Bosch-Strasse 38, 67056, Ludwigshafen, Germany
| | - Miriam Kary-Heinrich
- Experimental Ecotoxicology, BASF SE, Carl-Bosch-Strasse 38, 67056, Ludwigshafen, Germany
| | - Philipp W Hopp
- Regulatory Ecotoxicology, BASF Personal Care and Nutrition GmbH, Henkelstrasse 67, 40589, Düsseldorf, Germany
| | - Rüdiger Lukas
- Product Stewardship, BASF SE, Carl-Bosch-Strasse 38, 67056, Ludwigshafen, Germany
| | - Sabine Zok
- Experimental Ecotoxicology, BASF SE, Carl-Bosch-Strasse 38, 67056, Ludwigshafen, Germany
| | - Björn Hidding
- Experimental Ecotoxicology, BASF SE, Carl-Bosch-Strasse 38, 67056, Ludwigshafen, Germany
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16
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Tabra K, Arellano EC, Contreras S, Ginocchio R. Evaluation of phytotoxic effects of cationic polyacrylamide polymers: implication for the use of sludges as organic soil amendments in assisted phytostabilization. INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2020; 22:1068-1074. [PMID: 32129081 DOI: 10.1080/15226514.2020.1726870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Sludges, as biosolids, are organic soil amendments commonly used in assisted phytostabilitation. Extensive studies on their environmental impacts exists, particularly for improper land application and contents of trace elements, organic compounds and pathogens, but not for their content of cationic polyacrylamide polymers (C-PAMs). Direct toxicity of C-PAMs on aquatic organisms has been demonstrated but scarce information about plant toxicity is available. In this study, the effect of C-PAMs on early plant growth was evaluated by means of standard toxicity assays. Firstly, increasing doses of C-PAMs were applied as solutions to seeds of Avena sativa, Lactuca sativa and Solanum lycopersycum to evaluate germination and root elongation. Secondly, the effect of increasing doses of C-PAMs spiked in pig manure and mixed with sand (75 t ha-1 dry base) was evaluated on the emergence, radicle elongation and biomass of A. sativa. Results showed high phytotoxicity of C-PAMs in solutions above 1,000 mg L-1, but no effect was detected when spiked into experimental substrate; a significant effect was only observed above 5,000 mg L-1 for radicle elongation, aerial biomass, and radicle biomass. Results demonstrate direct phytotoxic effects of C-PAMs, which can be mitigated when spiked into an organic (pig manure) and mineral (sand) matrix.
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Affiliation(s)
- Kathia Tabra
- Facultad de Agronomía e Ingeniería Forestal, Pontificia Universidad Católica de Chile, Santiago, Chile
- Center of Applied Ecology and Sustainability (CAPES), Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Eduardo C Arellano
- Facultad de Agronomía e Ingeniería Forestal, Pontificia Universidad Católica de Chile, Santiago, Chile
- Center of Applied Ecology and Sustainability (CAPES), Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Samuel Contreras
- Facultad de Agronomía e Ingeniería Forestal, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Rosanna Ginocchio
- Facultad de Agronomía e Ingeniería Forestal, Pontificia Universidad Católica de Chile, Santiago, Chile
- Center of Applied Ecology and Sustainability (CAPES), Pontificia Universidad Católica de Chile, Santiago, Chile
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Sanderson H, Khan K, Brun Hansen AM, Connors K, Lam MW, Roy K, Belanger S. Environmental Toxicity (Q)SARs for Polymers as an Emerging Class of Materials in Regulatory Frameworks, with a Focus on Challenges and Possibilities Regarding Cationic Polymers. METHODS IN PHARMACOLOGY AND TOXICOLOGY 2020. [DOI: 10.1007/978-1-0716-0150-1_28] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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18
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Martins N, Pereira JL, Antunes FE, Melro E, Duarte CMG, Dias L, Soares AMVM, Lopes I. Role of surfactant headgroups on the toxicity of SLE nS-LAS mixed micelles: A case study using microtox test. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 643:1366-1372. [PMID: 30189553 DOI: 10.1016/j.scitotenv.2018.06.293] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 06/22/2018] [Accepted: 06/24/2018] [Indexed: 06/08/2023]
Abstract
Mixtures containing ether sulfate based surfactants (SLEnS) and linear alkylbenzene sulfonic acid (LAS) are relatively common in personal care and household products. When in mixture, they form mixed micelles, which act as reservoirs for the cleaning process. The increase of ethylene oxide (EO) units in the head of SLEnS lowers the critical micelle concentration, meaning that less quantity of each surfactant is needed to form the micelles. Within an eco-friendly perspective this is advantageous since less chemicals are expected to be released into the environment. But, this advantage will only be effective if variations with the higher number of EO units exhibit a lower toxicity as well. Despite its wide use in commercial products, the ecotoxicity of these micelles and the influence of the EO units on their toxicity still did not receive the necessary attention. In this context, the present study aimed at assessing the influence of the number of ethylene oxide (EO) units in the head groups of SLEnS on the toxicity of the SLEnS-LAS mixed micelles to the bacterium Vibrio fischeri (Microtox® assay, here used as a fast and preliminary ecotoxicological indicator). The SLEnS variants with fewer EO units showed higher toxicity relatively to those with more EO units - EC50 range (0-50 EO units): 0.56-8.59 mg L-1, thus they can be suggested as environmentally safer variants to be used in personal care and household products. Provided the consistency of Microtox® results as obtained here, this quick and cost-effective procedure can be an important tool towards the development of eco-friendlier surfactant-based formulations.
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Affiliation(s)
- Nuno Martins
- Department of Biology & CESAM, University of Aveiro, Aveiro, Portugal
| | - Joana L Pereira
- Department of Biology & CESAM, University of Aveiro, Aveiro, Portugal
| | - Filipe E Antunes
- Department of Chemistry, University of Coimbra, Coimbra, Portugal
| | - Elodie Melro
- Department of Chemistry, University of Coimbra, Coimbra, Portugal
| | | | - Lídia Dias
- Department of Biology & CESAM, University of Aveiro, Aveiro, Portugal
| | | | - Isabel Lopes
- Department of Biology & CESAM, University of Aveiro, Aveiro, Portugal.
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