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Mutoti MI, Jideani AI, Madala NE, Gumbo JR. The occurrence and human health risk assessment of microcystins in diverse food matrixes during production. Heliyon 2024; 10:e29882. [PMID: 38681651 PMCID: PMC11053293 DOI: 10.1016/j.heliyon.2024.e29882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 04/15/2024] [Accepted: 04/17/2024] [Indexed: 05/01/2024] Open
Abstract
Globally, the presence of cyanotoxins in water supplies and food has been widely investigated for over a decade. Cyanotoxins are harmful metabolites produced by toxic cyanobacterial genera. These metabolites belong to diverse chemical classes, with a variety of physicochemical properties, chemical structures, and toxic activities. The present study seeks to investigate the occurrence of cyanotoxins in water supplies destined for food processing and assess the human health risk from exposure to cyanotoxins. To achieve this, a simple, sensitive, and reliable analytical method was developed for the determination of microcystins (MC-RR, MC-LR, MC-YR) in process water, raw maize meal, and cooked maize (porridge) at ppb (parts per billion) levels. These compounds were extracted using Solid Phase Extraction (SPE) with optimized parameters; thereafter, Liquid Chromatography-tandem Mass Spectrometry (LC-MS/MS) was used for the rapid determination of the analytes selected for the present study. The method developed was applied to samples collected from the meal grinding station located in Mawoni village in South Africa; and was able to detect and quantify all the target cyanotoxins. MC-LR, MC-YR and MC-RR were detected at concentrations ranging from 10 to 11.2 μg/L, 9.1-9.4 μg/L, and 2.3-3.5 μg/L, in water samples, respectively. However, MC-YR was not detected in ground water sample. Moreover, MC-LR, MC-YR, and MC-RR concentrations in maize and porridge samples ranged between 9.2 and 11.2, 5.5-8.6, and 6.3-9.3 μg/kg dry weight, respectively. The hazard quotient index (HQi) levels found in the present study ranged between 2.2 - 8.4 and 0.11-8.9 for adults and children, respectively, representing potential risks to human health. Findings from LC-MS/MS reveal that cyanotoxins can be transferred from water to food during food processing using cyanotoxins contaminated water. Furthermore, the methods developed can be used by environmental and health agencies to strengthen the monitoring of cyanotoxins in water and food.
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Affiliation(s)
- Mulalo I. Mutoti
- Department of Environmental, Water, and Earth Sciences, Faculty of Science, Tshwane University of Technology, Pretoria, 0083, South Africa
| | - Afam I.O. Jideani
- Department of Food Science and Technology, Faculty of Science, Engineering and Agriculture, University of Venda, Private Bag X5050, Thohoyandou, 0950, South Africa
| | - Ntakadzeni E. Madala
- Department of Biochemistry and Microbiology, Faculty of Science, Engineering and Agriculture, University of Venda, Private Bag X5050, Thohoyandou, 0950, South Africa
| | - Jabulani R. Gumbo
- Department of Earth Sciences, Faculty of Science, Engineering and Agriculture, University of Venda, Private Bag X5050, Thohoyandou, 0950, South Africa
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Mutoti MI, Edokpayi J, Mutileni N, Durowoju O, Munyai FL. Cyanotoxins in groundwater; occurrence, potential sources, health impacts and knowledge gap for public health. Toxicon 2023; 226:107077. [PMID: 36893989 DOI: 10.1016/j.toxicon.2023.107077] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 01/27/2023] [Accepted: 03/06/2023] [Indexed: 03/11/2023]
Abstract
Groundwater is a significant source of water across the world and constitutes about 30% of the earth's freshwater. This water source is likely to be contaminated by cyanobacteria that produce secondary metabolites called cyanotoxins. Studies on contamination of groundwater by cyanobacteria have been sketchy with limited information. There is a need for better evidence regarding groundwater contamination by cyanobacteria as their presence in surface water bodies could cause contamination of groundwater via infiltration and percolation during rainfall events or during groundwater-surface water interaction, bank infiltration or water quality exchange. Therefore, this review is aimed at exploring the occurrences and potential sources of cyanotoxins in groundwater. This was achieved by summarising the existing data on the occurrence of cyanobacteria in groundwater and their potential sources across the world. Groundwater cyanobacteria contamination can possibly pose threat to water quality because many of the cyanotoxins produced by cyanobacteria pose a severe threat to human health, animals and the environment. Concentrations of microcystins (MCs) in groundwater have been recorded in China (Chaohu), Saudi Arabia, and China (Huai River Basin), with concentrations of 1.446 μg/L, 1.8 μg/L and 1.07 μg/L, respectively. In humans, exposure to these cyanotoxins can cause symptoms such as vomiting, diarrhea, and skin irritation, to mention a few. This work highlights the importance of providing information or knowledge regarding public health implications of exposure to groundwater contaminated with cyanotoxins and the need to undertake risk management actions through national and international regulation. This review also points out current knowledge gaps, which could lead to future research.
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Affiliation(s)
- Mulalo Isaih Mutoti
- Department of Earth Sciences, Faculty of Science, Engineering and Agriculture, University of Venda, Private Bag X5050, University Road, Thohoyandou, Limpopo, South Africa.
| | - Joshua Edokpayi
- Department of Geography and Environmental Sciences, Faculty of Science, Engineering and Agriculture, University of Venda, Private Bag X5050, University Road, Thohoyandou, Limpopo, South Africa
| | - Ntwanano Mutileni
- Department of Earth Sciences, Faculty of Science, Engineering and Agriculture, University of Venda, Private Bag X5050, University Road, Thohoyandou, Limpopo, South Africa
| | - Olatunde Durowoju
- Department of Earth Sciences, Faculty of Science, Engineering and Agriculture, University of Venda, Private Bag X5050, University Road, Thohoyandou, Limpopo, South Africa
| | - Fhatuwani Linton Munyai
- School of Biology and Environmental Sciences, Faculty of Agriculture and Natural Sciences, University of Mpumalanga, Nelspruit, 1201, South Africa
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3
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Guo X, Li Z, Jiang Q, Cheng C, Feng Y, He Y, Zuo L, Rao L, Ding W, Feng L. Structural insight into the substrate-binding mode and catalytic mechanism for MlrC enzyme of Sphingomonas sp. ACM-3962 in linearized microcystin biodegradation. Front Microbiol 2023; 14:1057264. [PMID: 36876080 PMCID: PMC9982164 DOI: 10.3389/fmicb.2023.1057264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 01/24/2023] [Indexed: 02/19/2023] Open
Abstract
Removing microcystins (MCs) safely and effectively has become an urgent global problem because of their extremely hazardous to the environment and public health. Microcystinases derived from indigenous microorganisms have received widespread attention due to their specific MC biodegradation function. However, linearized MCs are also very toxic and need to be removed from the water environment. How MlrC binds to linearized MCs and how it catalyzes the degradation process based on the actual three-dimensional structure have not been determined. In this study, the binding mode of MlrC with linearized MCs was explored using a combination of molecular docking and site-directed mutagenesis methods. A series of key substrate binding residues, including E70, W59, F67, F96, S392 and so on, were identified. Sodium dodecane sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to analyze samples of these variants. The activity of MlrC variants were measured using high performance liquid chromatography (HPLC). We used fluorescence spectroscopy experiments to research the relationship between MlrC enzyme (E), zinc ion (M), and substrate (S). The results showed that MlrC enzyme, zinc ion and substrate formed E-M-S intermediates during the catalytic process. The substrate-binding cavity was made up of N and C-terminal domains and the substrate-binding site mainly included N41, E70, D341, S392, Q468, S485, R492, W59, F67, and F96. The E70 residue involved in both substrate catalysis and substrate binding. In conclusion, a possible catalytic mechanism of the MlrC enzyme was further proposed based on the experimental results and a literature survey. These findings provided new insights into the molecular mechanisms of the MlrC enzyme to degrade linearized MCs, and laid a theoretical foundation for further biodegradation studies of MCs.
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Affiliation(s)
- Xiaoliang Guo
- Key Laboratory of Pesticide and Chemical Biology (CCNU), Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, China
| | - Zengru Li
- The Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Qinqin Jiang
- Key Laboratory of Pesticide and Chemical Biology (CCNU), Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, China
| | - Cai Cheng
- Key Laboratory of Pesticide and Chemical Biology (CCNU), Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, China
| | - Yu Feng
- Key Laboratory of Pesticide and Chemical Biology (CCNU), Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, China
| | - Yanlin He
- Key Laboratory of Pesticide and Chemical Biology (CCNU), Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, China
| | - Lingzi Zuo
- Key Laboratory of Pesticide and Chemical Biology (CCNU), Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, China
| | - Li Rao
- Key Laboratory of Pesticide and Chemical Biology (CCNU), Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, China
| | - Wei Ding
- The Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Lingling Feng
- Key Laboratory of Pesticide and Chemical Biology (CCNU), Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, China
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Han F, Chen G, Tao G, Xu J, Zhang H, Zhang L, Li H, Zhao Y, Tian D, Kimura SY, Wei X, Ruan Y, Wu C, Xiao S, Zhan M, Zheng W. Thyroid-disrupting effects caused by exposure to alternative flame retardants from groundwater contamination in rural central China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 839:156300. [PMID: 35636535 DOI: 10.1016/j.scitotenv.2022.156300] [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: 12/28/2021] [Revised: 05/12/2022] [Accepted: 05/24/2022] [Indexed: 06/15/2023]
Abstract
Accumulating evidence reveals that exposure to alternative flame retardants (AFRs) results in defective thyroid functions. AFRs are detectable in various environmental media in developed cities in China. However, few studies have reported the contamination levels of AFR in groundwater in rural areas, indicating an urgent need to investigate exposure of AFRs and perform health risk assessment for populations that use groundwater as the main source of drinking water. This study investigated the concentrations of AFRs in groundwater in rural areas of central China. Moreover, Nthy-ori-3-1 cells were used to determine the thyroid cytotoxicities and thyroid-interfering effects of a single AFR as well as the mixtures of AFRs based on the AFR contamination levels in real-world. The results revealed that all classes of AFRs were detectable in rural areas in central China. Dechlorane plus, hexabromocyclododecane, bromophenols (BPs), novel brominated flame retardants (NBFRs) and organophosphate flame retardants (OPFRs) exhibited spatial contamination patterns, with an average concentrations (median) of 157.89 ± 88.61 (185.47) pg/L, 0.09 ± 0.29 (not detectable) ng/L, 5.20 ± 5.92 (3.43) ng/L, 3338.11 ± 3758.78 (2836.72) pg/L, and 79.35 ± 97.19 (53.62) ng/L, respectively. The half maximal effective concentrations (EC50) of BPs, OPFRs, and NBFRs ranged 98.4-4012 μM, 42.0-2506 μM, and 10.1-203.7 μM, respectively. Several AFRs exhibited more cytotoxic effects than did traditional brominated flame retardants. It is intriguing that several single AFRs and mixtures at environmentally-relevant exposure levels promoted the viability of Nthy-ori-3-1 cells. Taken together, our study demonstrates that AFRs are present in the groundwater in rural areas in central China and AFRs exhibit thyroid disrupting effects.
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Affiliation(s)
- Fengchan Han
- Key Laboratory of the Public Health Safety, Ministry of Education, Department of Environmental Health, School of Public Health, Fudan University, Shanghai 200032, PR China; Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, PR China
| | - Guanghua Chen
- Key Laboratory of the Public Health Safety, Ministry of Education, Department of Environmental Health, School of Public Health, Fudan University, Shanghai 200032, PR China
| | - Gonghua Tao
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, PR China
| | - Jingshan Xu
- School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, PR China
| | - Huijun Zhang
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, PR China
| | - Ling Zhang
- Department of Surgery, Huangpu Branch, Shanghai Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai 200011, China
| | - Hongliang Li
- Shanghai Pudong New Area Center for Disease Control and Prevention, Fudan University Pudong Institute of Preventive Medicine, Shanghai 200136, PR China
| | - Yijing Zhao
- Shanghai Pudong New Area Center for Disease Control and Prevention, Fudan University Pudong Institute of Preventive Medicine, Shanghai 200136, PR China
| | - Dajun Tian
- Department of Epidemiology and Biostatistics, College for Public Health and Social Justice, 3545 Lafayette Ave., St. Louis, MO 63104, USA
| | - Susana Y Kimura
- Department of Chemistry, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Xiao Wei
- Department of Occupational and Environmental Health, School of Public Health, Guangxi Medical University, Nanning, Guangxi 530021, PR China
| | - Yuanyuan Ruan
- NHC Key Laboratory of Glycoconjugates Research, School of Basic Medical Sciences, Fudan University, Shanghai 200032, PR China; Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, PR China
| | - Chunfeng Wu
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, PR China
| | - Shuo Xiao
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, NJ 08854, USA.
| | - Ming Zhan
- Shanghai Pudong New Area Center for Disease Control and Prevention, Fudan University Pudong Institute of Preventive Medicine, Shanghai 200136, PR China.
| | - Weiwei Zheng
- Key Laboratory of the Public Health Safety, Ministry of Education, Department of Environmental Health, School of Public Health, Fudan University, Shanghai 200032, PR China; Center for Water and Health, School of Public Health, Fudan University, Shanghai 200032, PR China.
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Mohamed ZA, Alamri S, Hashem M. The link between microcystin levels in groundwater and surface Nile water, and assessing their potential risk to human health. JOURNAL OF CONTAMINANT HYDROLOGY 2022; 244:103921. [PMID: 34784559 DOI: 10.1016/j.jconhyd.2021.103921] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 10/30/2021] [Accepted: 11/06/2021] [Indexed: 06/13/2023]
Abstract
Although groundwater is an important source for drinking and irrigation water worldwide, particularly in arid countries, they have been paid little attention to their contamination with microcystins (MCs) compared to surface water. Our study is the fourth one reporting existence of MCs in groundwater due to surface-water and groundwater interaction. Dissolved MCs in groundwater were found with higher concentrations in summer (0.1 to 0.84 μg L-1) than in winter (0-0.06 μg L-1), in association with MCs detected in nearby surface Nile water. The chronic daily intake (CDI) of MCs for both adults and children (0-0.003 μg kg-1 body weight d-1) in groundwater were lower than the chronic reference dose (RfD, 0.003 μg kg-1 body weight d-1) during winter, with hazard quotient less than 1. Conversely, CDI values exceeded the reference dose during summer for both adults (0.005-0.024 μg kg-1 body weight d-1) and children (0.012-0.05 μg kg-1 body weight d-1), with hazard quotient greater than 1. This indicates that MCs concentrations in these groundwater wells might pose adverse health effects to both adults and children during summer, but not during winter. The study provides evidence for the risk of cyanotoxins in groundwater close to cyanobacteria-contaminated surface water. Therefore, regular monitoring for cyanotoxins in groundwater supplies used for drinking-water should be undertaken when cyanobacteria bloom events are noted in nearby surface waters.
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Affiliation(s)
- Zakaria A Mohamed
- Department of Botany and Microbiology, Faculty of Science, Sohag University, Sohag 82524, Egypt..
| | - Saad Alamri
- King Khalid University, Faculty of Science, Biological Science Department, P.O. Box 61413, Abha, Saudi Arabia
| | - Mohamed Hashem
- King Khalid University, Faculty of Science, Biological Science Department, P.O. Box 61413, Abha, Saudi Arabia; Assiut University, Faculty of Science, Botany and Microbiology Department, Assiut 71516, Egypt
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6
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Pawlik-Skowrońska B, Bownik A. Synergistic toxicity of some cyanobacterial oligopeptides to physiological activities of Daphnia magna (Crustacea). Toxicon 2021; 206:74-84. [PMID: 34942216 DOI: 10.1016/j.toxicon.2021.12.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 12/03/2021] [Accepted: 12/14/2021] [Indexed: 01/18/2023]
Abstract
Anabaenopeptins and microcystins are oligopeptides produced by bloom-forming cyanobacteria. We determined in vivo effects of anabaenopeptin-B (AN-B) and two variants of microcystins of different hydrophobicity (MC-LR and MC-LF) on the physiology of Daphnia magna. Heart rate, thoracic limb activity and post-abdominal claw activity were determined by digital video analysis and oxygen consumption by Oxygraph + system. EC50 calculation and isobole methodology for interactive effects of AN-B and MC-LR mixture were used. Daphnids' responses to all three oligopeptides were concentration- and time-dependent. MC-LF was the most potent inhibitor of heart rate, thoracic limb activity, post-abdominal claw activity and oxygen consumption. AN-B was more toxic than MC-LR toward oxygen consumption; it inhibited the movements of limbs and post-abdominal claw similarly to MC-LR, but did not inhibit heart rate. The strongest toxic effects were induced by the binary mixture of AN-B with MC-LR at the sum concentration equal to the concentration of the single compounds. First time direct synergistic toxic effects of the cyanopeptides on all the physiological parameters were found. The obtained results explain stronger disturbances in aquatic organisms caused by cyanobacterial cell contents than the individual cyanopeptides present even at higher concentrations. Other metabolites and their interactions need further studies.
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Affiliation(s)
- Barbara Pawlik-Skowrońska
- Department of Hydrobiology and Protection of Ecosystems, Faculty of Environmental Biology, University of Life Sciences in Lublin, Dobrzańskiego 37, 20-262 Lublin, Poland.
| | - Adam Bownik
- Department of Hydrobiology and Protection of Ecosystems, Faculty of Environmental Biology, University of Life Sciences in Lublin, Dobrzańskiego 37, 20-262 Lublin, Poland
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Huo D, Gan N, Geng R, Cao Q, Song L, Yu G, Li R. Cyanobacterial blooms in China: diversity, distribution, and cyanotoxins. HARMFUL ALGAE 2021; 109:102106. [PMID: 34815019 DOI: 10.1016/j.hal.2021.102106] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 09/14/2021] [Accepted: 09/14/2021] [Indexed: 06/13/2023]
Abstract
Cyanobacterial blooms, which refer to the massive growth of harmful cyanobacteria, have altered the global freshwater ecosystems during the past decades. China has the largest population in the world, and it is suffering from the harmful effect of water eutrophication and cyanobacterial blooms along with rapid development of the economy and society. Research on cyanobacterial blooms and cyanotoxins in China have been overwhelmingly enhanced and emphasized during the past decades. In the present review, the research on cyanobacterial blooms in China is generally introduced, including the history of cyanobacterial bloom studies, the diversity of the bloom-forming cyanobacteria species (BFCS), and cyanotoxin studies in China. Most studies have focused on Microcystis, its blooms, and microcystins. Newly emerging blooms with the dominance of non-Microcystis BFCS have been gradually expanding to wide regions in China. Understanding the basic features of these non-Microcystis BFCS and their blooms, including their diversity, occurrence, physio-ecology, and harmful metabolites, will provide direction on future studies of cyanobacterial blooms in China.
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Affiliation(s)
- Da Huo
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Nanqin Gan
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Ruozhen Geng
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China; University of Chinese Academy of Sciences, Beijing 400049, PR China
| | - Qi Cao
- Tianjin Key Laboratory of Aqua-Ecology and Aquaculture, College of Fisheries, Tianjin Agricultural University, Tianjin 300384, PR China
| | - Lirong Song
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Gongliang Yu
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Renhui Li
- College of Life and Environmental Sciences, Wenzhou University, Wenzhou 325000, PR China.
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Liu BL, Li YW, Tu XY, Yu PF, Xiang L, Zhao HM, Feng NX, Li H, Cai QY, Mo CH, Wong MH. Variant-Specific Adsorption, Desorption, and Dissipation of Microcystin Toxins in Surface Soil. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:11825-11834. [PMID: 34582220 DOI: 10.1021/acs.jafc.1c03918] [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] [Indexed: 06/13/2023]
Abstract
Microcystins (MCs) are hepatotoxic heptapeptides identified in cyanobacterial bloom-impacted waters and soils. However, their environmental fate in soils is poorly understood, preventing reliable site assessment. This study aims to clarify the variant-specific adsorption, desorption, and dissipation of MC-LR and MC-RR in agricultural soils. Results revealed that their adsorption isotherms followed the Freundlich model (R2 ≥ 0.96), exhibiting a higher nonlinear trend and lower adsorption capacity for MC-LR than for MC-RR. The soils had low desorption rates of 8.14-21.06% and 3.06-34.04%, respectively, following a 24 h desorption cycle. Pairwise comparison indicated that soil pH and clay played key roles in MC-LR adsorption and desorption, while organic matter and cation exchange capacity played key roles in those of MC-RR. MC-LR dissipation half-lives in soils were 27.18-42.52 days, compared with 35.19-43.87 days for MC-RR. Specifically, an appreciable decrease in MC concentration in sterile soils suggested the significant role of abiotic degradation. This study demonstrates that the minor structural changes in MCs might have major effects on their environmental fates in agricultural soil and indicates that the toxic effects of MCs should be of high concern due to high adsorption, low desorption, and slow dissipation.
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Affiliation(s)
- Bai-Lin Liu
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Yan-Wen Li
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Xi-Ying Tu
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Peng-Fei Yu
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Lei Xiang
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Hai-Ming Zhao
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Nai-Xian Feng
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Hui Li
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Quan-Ying Cai
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Ce-Hui Mo
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Ming Hung Wong
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
- Consortium on Health, Environment, Education and Research (CHEER), Department of Science and Environmental Studies, The Education University of Hong Kong, Tai Po, Ting Kok 999077, Hong Kong, China
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Zhang M, Daraz U, Sun Q, Chen P, Wei X. Denitrifier abundance and community composition linked to denitrification potential in river sediments. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:51928-51939. [PMID: 33990922 DOI: 10.1007/s11356-021-14348-w] [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: 08/10/2020] [Accepted: 05/06/2021] [Indexed: 06/12/2023]
Abstract
Denitrification in river sediments plays a very important role in removing nitrogen in aquatic ecosystem. To gain insight into the key factors driving denitrification at large spatial scales, a total of 135 sediment samples were collected from Huaihe River and its branches located in the northern of Anhui province. Bacterial community composition and denitrifying functional genes (nirS, nirK, and nosZ) were measured by high-throughput sequencing and real-time PCR approaches. Potential denitrification rate (PDR) was measured by acetylene inhibition method, which varied from 0.01 to 15.69 μg N g-1 h-1. The sequencing results based on 16S rRNA gene found that the main denitrification bacterial taxa included Bacillus, Thiobacillus, Acinetobacter, Halomonas, Denitratisoma, Pseudomonas, Rhodanobacter, and Thauera. Therein, Thiobacillus might play key roles in the denitrification. Total nitrogen and N:P ratio were the only chemical factors related with all denitrification genes. Furthermore, nirS gene abundance could be more susceptible to environmental parameters compared with nirK and nosZ genes. Canonical correspondence analysis indicated that NO3-, NO2-, NH4+ and IP had the significant impacts on the nirS-encoding bacterial community and spatial distributions. There was a significantly positive correlation between Thiobacillus and nirS gene. We considered that higher numbers of nosZ appeared in nutrient rich sediments. More strikingly, PDR was positively correlated with the abundance of three functional genes. Random forest analysis showed that NH4+ was the most powerful predictor of PDR. These findings can yield practical and important reference for the bioremediation or evaluation of wetland systems.
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Affiliation(s)
- Mingzhu Zhang
- School of Resources and Environmental Engineering, Anhui University, Hefei, 230601, Anhui Province, China
- Key Laboratory of Wetland Ecological Protection and Restoration, Hefei, China
- Anhui Province Engineering Laboratory for Mine Ecological Remediation, Hefei, China
| | - Umar Daraz
- School of Resources and Environmental Engineering, Anhui University, Hefei, 230601, Anhui Province, China
| | - Qingye Sun
- School of Resources and Environmental Engineering, Anhui University, Hefei, 230601, Anhui Province, China.
- Key Laboratory of Wetland Ecological Protection and Restoration, Hefei, China.
- Anhui Province Engineering Laboratory for Mine Ecological Remediation, Hefei, China.
| | - Piaoxue Chen
- School of Resources and Environmental Engineering, Anhui University, Hefei, 230601, Anhui Province, China
- Key Laboratory of Wetland Ecological Protection and Restoration, Hefei, China
- Anhui Province Engineering Laboratory for Mine Ecological Remediation, Hefei, China
| | - Xuhao Wei
- School of Resources and Environmental Engineering, Anhui University, Hefei, 230601, Anhui Province, China
- Key Laboratory of Wetland Ecological Protection and Restoration, Hefei, China
- Anhui Province Engineering Laboratory for Mine Ecological Remediation, Hefei, China
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Role of Rhizospheric Microbiota as a Bioremediation Tool for the Protection of Soil-Plant Systems from Microcystins Phytotoxicity and Mitigating Toxin-Related Health Risk. Microorganisms 2021; 9:microorganisms9081747. [PMID: 34442826 PMCID: PMC8402104 DOI: 10.3390/microorganisms9081747] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 08/03/2021] [Accepted: 08/13/2021] [Indexed: 11/16/2022] Open
Abstract
Frequent toxic cyanoblooms in eutrophic freshwaters produce various cyanotoxins such as the monocyclic heptapeptides microcystins (MCs), known as deleterious compounds to plant growth and human health. Recently, MCs are a recurrent worldwide sanitary problem in irrigation waters and farmland soils due to their transfer and accumulation in the edible tissues of vegetable produce. In such cases, studies about the persistence and removal of MCs in soil are scarce and not fully investigated. In this study, we carried out a greenhouse trial on two crop species: faba bean (Vicia faba var. Alfia 321) and common wheat (Triticum aestivum var. Achtar) that were grown in sterile (microorganism-free soil) and non-sterile (microorganism-rich soil) soils and subjected to MC-induced stress at 100 µg equivalent MC-LR L−1. The experimentation aimed to assess the prominent role of native rhizospheric microbiota in mitigating the phytotoxic impact of MCs on plant growth and reducing their accumulation in both soils and plant tissues. Moreover, we attempted to evaluate the health risk related to the consumption of MC-polluted plants for humans and cattle by determining the estimated daily intake (EDI) and health risk quotient (RQ) of MCs in these plants. Biodegradation was liable to be the main removal pathway of the toxin in the soil; and therefore, bulk soil (unplanted soil), as well as rhizospheric soil (planted soil), were used in this experiment to evaluate the accumulation of MCs in the presence and absence of microorganisms (sterile and non-sterile soils). The data obtained in this study showed that MCs had no significant effects on growth indicators of faba bean and common wheat plants in non-sterile soil as compared to the control group. In contrast, plants grown in sterile soil showed a significant decrease in growth parameters as compared to the control. These results suggest that MCs were highly bioavailable to the plants, resulting in severe growth impairments in the absence of native rhizospheric microbiota. Likewise, MCs were more accumulated in sterile soil and more bioconcentrated in root and shoot tissues of plants grown within when compared to non-sterile soil. Thereby, the EDI of MCs in plants grown in sterile soil was more beyond the tolerable daily intake recommended for both humans and cattle. The risk level was more pronounced in plants from the sterile soil than those from the non-sterile one. These findings suggest that microbial activity, eventually MC-biodegradation, is a crucial bioremediation tool to remove and prevent MCs from entering the agricultural food chain.
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Modley LAS, Rampedi IT, Avenant-Oldewage A, Mhuka V, Nindi M, Van Dyk C. Microcystin concentrations and liver histopathology in Clarias gariepinus and Oreochromis mossambicus from three impacted rivers flowing into a hyper-eutrophic freshwater system: A pilot study. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2019; 71:103222. [PMID: 31426013 DOI: 10.1016/j.etap.2019.103222] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 07/12/2019] [Accepted: 07/16/2019] [Indexed: 06/10/2023]
Abstract
The Roodeplaat Dam and its three inflowing rivers are highly impacted by surrounding anthropogenic activities. The system is hyper-eutrophic and characterized by seasonal algal blooms and previous studies have reported levels of the hepatotoxin microcystin in the water of the impoundment. Limited information is available on the microcystin concentrations in the inflowing rivers and no information is available on the bioaccumulated levels and potential health effects in fish inhabiting these rivers. The aim of this study was to do a histopathological assessment and to determine the concentrations of bioaccumulated microcystins in the livers of two indicator fish species Clarias gariepinus and Oreochromis mossambicus. The results showed that the two species bioaccumulate microcystins at different concentrations and that their hepatic health response varied. The liver index was significantly higher for C. gariepinus compared to O. mossambicus. No significant positive correlation was found between the bioaccumulated microcystin levels and the liver histology index. It is recommended that this pilot study be followed by a controlled exposure study to confirm a possible cause and effect relationship between microcystin exposure and the specific liver alterations identified.
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Affiliation(s)
- Lee-Ann S Modley
- Department of Geography, Energy and Environmental Management, University of Johannesburg, PO Box 524, Auckland Park 2006, South Africa
| | - Isaac T Rampedi
- Department of Geography, Energy and Environmental Management, University of Johannesburg, PO Box 524, Auckland Park 2006, South Africa
| | | | - Vimbai Mhuka
- Department of Chemistry, College of Science, The Science Campus, Engineering and Technology, University of South Africa, Florida park, Roodepoort, 1709, South Africa
| | - Mathew Nindi
- Department of Chemistry, College of Science, The Science Campus, Engineering and Technology, University of South Africa, Florida park, Roodepoort, 1709, South Africa
| | - Cobus Van Dyk
- Department of Zoology, University of Johannesburg, PO Box 524, Auckland Park 2006, South Africa.
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Díez-Quijada L, Puerto M, Gutiérrez-Praena D, Llana-Ruiz-Cabello M, Jos A, Cameán AM. Microcystin-RR: Occurrence, content in water and food and toxicological studies. A review. ENVIRONMENTAL RESEARCH 2019; 168:467-489. [PMID: 30399604 DOI: 10.1016/j.envres.2018.07.019] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 07/09/2018] [Accepted: 07/09/2018] [Indexed: 06/08/2023]
Abstract
Microcystins (MCs) are hepatotoxins, produced by various species of cyanobacteria, whose occurrence is increasing worldwide owing to climate change and anthropogenic activities. More than 100 variants have been reported, and among them MC-LR is the most extensively studied, but there are other MC congeners that deserve to be investigated. The need for data to characterize the toxicological profile of MC variants other than MC-LR has been identified in order to improve risk assessment in humans and wildlife. Accordingly, the aim of this study was to evaluate the information available in the scientific literature dealing with MC-RR, as this congener is the second most common cyanotoxin in the environment. The review focuses on aspects such as occurrence in water and food, and toxicity studies both in vitro and in vivo. It reveals that, although MC-RR is a real hazard with a high exposure potential in some countries, little is known yet about its specific toxicological properties that differ from those of MC-LR, and important aspects such as genotoxicity and chronic effects have not yet been sufficiently addressed.
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Affiliation(s)
- Leticia Díez-Quijada
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012 Sevilla, Spain
| | - María Puerto
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012 Sevilla, Spain.
| | - Daniel Gutiérrez-Praena
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012 Sevilla, Spain
| | - María Llana-Ruiz-Cabello
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012 Sevilla, Spain
| | - Angeles Jos
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012 Sevilla, Spain
| | - Ana M Cameán
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012 Sevilla, Spain
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Díez-Quijada L, Prieto AI, Guzmán-Guillén R, Jos A, Cameán AM. Occurrence and toxicity of microcystin congeners other than MC-LR and MC-RR: A review. Food Chem Toxicol 2018; 125:106-132. [PMID: 30597222 DOI: 10.1016/j.fct.2018.12.042] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 11/29/2018] [Accepted: 12/25/2018] [Indexed: 12/11/2022]
Abstract
The occurrence of cyanobacterial toxins is being increasingly reported. This is a reason for concern as they can induce toxic effects both in humans and in the environment. Among them, microcystins (MCs) are the best described and most diverse group of cyanobacterial toxins, and MC-LR and MC-RR are the congeners most widely investigated. However, the number of MC variants has also increased in recent years. Some of these minority variants have been shown to have a different toxicokinetic and toxicodynamic profile, but research focused on them is still limited. Moreover, in some water bodies these minority variants can be the predominant toxins. Nonetheless, MC-LR is the only one used for risk evaluation purposes at present. In order to contribute to more realistic risk assessments in the future, the aim of this review was to compile the available information in the scientific literature regarding the occurrence and concentration of minority MCs in water and food samples, and their toxic effects. The data retrieved demonstrate the congener-specific toxicity of MCs, as well as many data gaps in relation to analytical or mechanistic aspects, among others. Therefore, further research is needed to improve the toxicological characterization of these toxins and the exposure scenarios.
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Affiliation(s)
- Leticia Díez-Quijada
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012, Seville, Spain
| | - Ana I Prieto
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012, Seville, Spain
| | - Remedios Guzmán-Guillén
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012, Seville, Spain
| | - Angeles Jos
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012, Seville, Spain.
| | - Ana M Cameán
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012, Seville, Spain
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Zhang P, Lee J, Kang G, Li Y, Yang D, Pang B, Zhang Y. Disparity of nitrate and nitrite in vivo in cancer villages as compared to other areas in Huai River Basin, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 612:966-974. [PMID: 28886549 DOI: 10.1016/j.scitotenv.2017.08.245] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 08/06/2017] [Accepted: 08/23/2017] [Indexed: 06/07/2023]
Abstract
Saliva and Urine samples were collected for the study on how nitrate and nitrite concentration in human body may be related to the corresponding health risk in a high cancer incidence area. The study area includes three known cancer villages in Huai River basin, China. The results of analyzing collected sample show that there are higher levels of nitrate and nitrite concentration in human saliva and urine sample collected in the study area as compared to those collected in other areas. In addition, levels of nitrate and nitrite concentration in saliva and urine sample change significantly with the ages of sampled population. NO3-concentrations in saliva and urine sample are the most outstanding among the middle-aged and elderly populations. It means that the middle-aged and elderly populations have relatively high vivo nitrate reductive transformation rates and they also have higher N-nitroso compounds synthesis risks in the studied cancer villages.
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Affiliation(s)
- Pengyan Zhang
- College of Environment and Planning, Henan University, Kaifeng, Henan 475004, China; Department of Geography, Kent State University, Kent, OH 44242-0001, USA
| | - Jay Lee
- College of Environment and Planning, Henan University, Kaifeng, Henan 475004, China; Department of Geography, Kent State University, Kent, OH 44242-0001, USA.
| | - Guohua Kang
- College of Environment and Planning, Henan University, Kaifeng, Henan 475004, China
| | - Yanyan Li
- College of Environment and Planning, Henan University, Kaifeng, Henan 475004, China
| | - Dan Yang
- College of Environment and Planning, Henan University, Kaifeng, Henan 475004, China
| | - Bo Pang
- College of Environment and Planning, Henan University, Kaifeng, Henan 475004, China
| | - Yu Zhang
- College of Environment and Planning, Henan University, Kaifeng, Henan 475004, China
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15
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Lee S, Jiang X, Manubolu M, Riedl K, Ludsin SA, Martin JF, Lee J. Fresh produce and their soils accumulate cyanotoxins from irrigation water: Implications for public health and food security. Food Res Int 2017; 102:234-245. [PMID: 29195944 DOI: 10.1016/j.foodres.2017.09.079] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 09/21/2017] [Accepted: 09/25/2017] [Indexed: 01/18/2023]
Abstract
Microcystin (MC), a hepatotoxin that can adversely affect human health, has become more prevalent in freshwater ecosystems worldwide, owing to an increase in toxic cyanobacteria blooms. While consumption of water and fish are well-documented exposure pathways of MCs to humans, less is known about the potential transfer to humans through consumption of vegetables that have been irrigated with MC-contaminated water. Likewise, the impact of MC on the performance of food crops is understudied. To help fill these information gaps, we conducted a controlled laboratory experiment in which we exposed lettuce, carrots, and green beans to environmentally relevant concentrations of MC-LR (0, 1, 5, and 10μg/L) via two irrigation methods (drip and spray). We used ELISA and LC-MS/MS to quantify MC-LR concentrations and in different parts of the plant (edible vs. inedible fractions), measured plant performance (e.g., size, mass, edible leaves, color), and calculated human exposure risk based on accumulation patterns. MC-LR accumulation was positively dose-dependent, with it being greater in the plants (2.2-209.2μg/kg) than in soil (0-19.4μg/kg). MC-LR accumulation varied among vegetable types, between plant parts, and between irrigation methods. MC-LR accumulation led to reduced crop growth and quality, with MC-LR persisting in the soil after harvest. Observed toxin accumulation patterns in edible fractions of plants also led to estimates of daily MC-LR intake that exceeded both the chronic reference dose (0.003μg/kg of body weight) and total daily intake guidelines (0.04μg/kg of body weight). Because the use of MC-contaminated water is common in many parts of the world, our collective findings highlight the need for guidelines concerning the use of MC-contaminated water in irrigation, as well as consumption of these crops.
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Affiliation(s)
- Seungjun Lee
- Environmental Science Graduate Program, The Ohio State University, Columbus, OH 43210, USA
| | - Xuewen Jiang
- Department of Food Science and Technology, The Ohio State University, Columbus, OH 43210, USA
| | - Manjunath Manubolu
- Aquatic Ecology Laboratory, Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, OH 43210, USA; College of Public Health, Division of Environmental Health Sciences, The Ohio State University, Columbus, OH 43210, USA
| | - Ken Riedl
- Department of Food Science and Technology, The Ohio State University, Columbus, OH 43210, USA
| | - Stuart A Ludsin
- Environmental Science Graduate Program, The Ohio State University, Columbus, OH 43210, USA; Aquatic Ecology Laboratory, Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, OH 43210, USA
| | - Jay F Martin
- Environmental Science Graduate Program, The Ohio State University, Columbus, OH 43210, USA; Department of Food, Agricultural and Biological Engineering, The Ohio State University, Columbus, OH 43210, USA; Ohio Sea Grant, Columbus, OH 43210, USA
| | - Jiyoung Lee
- Environmental Science Graduate Program, The Ohio State University, Columbus, OH 43210, USA; Department of Food Science and Technology, The Ohio State University, Columbus, OH 43210, USA; College of Public Health, Division of Environmental Health Sciences, The Ohio State University, Columbus, OH 43210, USA.
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16
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McLellan NL, Manderville RA. Toxic mechanisms of microcystins in mammals. Toxicol Res (Camb) 2017; 6:391-405. [PMID: 30090507 PMCID: PMC6060792 DOI: 10.1039/c7tx00043j] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 04/21/2017] [Indexed: 01/08/2023] Open
Abstract
Microcystins, such as microcystin-leucine arginine (MC-LR), are some of the most toxic and prevalent cyanotoxins produced by cyanobacteria in freshwater and saltwater algal blooms worldwide. Acute and chronic exposures to microcystins are primarily known to cause hepatotoxicity; cellular damage and genotoxicity within mammalian livers. However, in vivo studies indicate that similar damage may occur in other mammalian organs and tissues, such as the kidney, heart, reproductive systems, and lungs - particularly following chronic low-dose exposures. Mechanisms of toxicity of mycrocystins are reviewed herein; including cellular uptake, interaction with protein phosphatases PP1 and PP2A, cytoskeletal effects, formation of oxidative stress and induction of apoptosis. In general, the mode of action of toxicity by MCs in mammalian organs are similar to those that have been observed in liver tissues. A comprehensive understanding of the toxic mechanisms of microcystins in mammalian tissues and organs will assist in the development of risk assessment approaches to public health protection strategies and the development of robust drinking water policies.
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Affiliation(s)
- Nicole L McLellan
- School of Environmental Sciences , University of Guelph , Guelph , Ontario N1G 2W1 , Canada
| | - Richard A Manderville
- Department of Chemistry and Toxicology , University of Guelph , Guelph , Ontario N1G 2W1 , Canada . ; ; Tel: +1-519-824-4120, x53963
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17
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Park JA, Jung SM, Yi IG, Choi JW, Kim SB, Lee SH. Adsorption of microcystin-LR on mesoporous carbons and its potential use in drinking water source. CHEMOSPHERE 2017; 177:15-23. [PMID: 28279901 DOI: 10.1016/j.chemosphere.2017.02.150] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 12/23/2016] [Accepted: 02/27/2017] [Indexed: 06/06/2023]
Abstract
Microcystin-LR (MC-LR) is a common toxin derived from cyanobacterial blooms an effective, rapid and non-toxic method needs to be developed for its removal from drinking water treatment plants (DWTP). For an adsorption-based method, mesoporous carbon can be a promising supplemental adsorbent. The effect of mesoporous carbon (MC1, MC2, and MC3) properties and water quality parameters on the adsorption of MC-LR were investigated and the results were analyzed by kinetic, isotherm, thermodynamic, Derjaguin-Landau-Verwey-Overbeek (DLVO), and intraparticle diffusion models. MC1 was the most appropriate type for the removal of MC-LR with a maximum adsorption capacity of 35,670.49 μg/g. Adsorption of MC-LR is a spontaneous reaction dominated by van der Waals interactions. Pore sizes of 8.5-14 nm enhance the pore diffusion of MC-LR from the surface to the mesopores of MC1. The adsorption capacity was not sensitive to changes in the pH (3.2-8.0) and the existence of organic matter (2-5 mg/L). Furthermore, the final concentration of MC-LR was below the WHO guideline level after a 10-min reaction with 20 mg/L of MC1 in the Nak-Dong River, a drinking water source. The MC-LR adsorption mainly competed with humic substances (500-1000 g/mole); however, they did not have a great effect on adsorption.
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Affiliation(s)
- Jeong-Ann Park
- Center for Water Resource Cycle, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea
| | - Sung-Mok Jung
- Center for Water Resource Cycle, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea
| | - In-Geol Yi
- Environment R&D Center, KORBI, Co., Ltd, Gyeonggi, 14059, Republic of Korea
| | - Jae-Woo Choi
- Center for Water Resource Cycle, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea
| | - Song-Bae Kim
- Department of Rural Systems Engineering and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Sang-Hyup Lee
- Center for Water Resource Cycle, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea; Green School, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea.
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18
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Loftin KA, Clark JM, Journey CA, Kolpin DW, Van Metre PC, Carlisle D, Bradley PM. Spatial and temporal variation in microcystin occurrence in wadeable streams in the southeastern United States. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2016; 35:2281-2287. [PMID: 26844812 DOI: 10.1002/etc.3391] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 12/07/2015] [Accepted: 02/02/2016] [Indexed: 06/05/2023]
Abstract
Despite historical observations of potential microcystin-producing cyanobacteria (including Leptolyngbya, Phormidium, Pseudoanabaena, and Anabaena species) in 74% of headwater streams in Alabama, Georgia, South Carolina, and North Carolina (USA) from 1993 to 2011, fluvial cyanotoxin occurrence has not been systematically assessed in the southeastern United States. To begin to address this data gap, a spatial reconnaissance of fluvial microcystin concentrations was conducted in 75 wadeable streams in the Piedmont region (southeastern USA) during June 2014. Microcystins were detected using enzyme-linked immunosorbent assay (limit = 0.10 µg/L) in 39% of the streams with mean, median, and maximum detected concentrations of 0.29 µg/L, 0.11 µg/L, and 3.2 µg/L, respectively. Significant (α = 0.05) correlations were observed between June 2014 microcystin concentrations and stream flow, total nitrogen to total phosphorus ratio, and water temperature; but each of these factors explained 38% or less of the variability in fluvial microcystins across the region. Temporal microcystin variability was assessed monthly through October 2014 in 5 of the streams where microcystins were observed in June and in 1 reference location; microcystins were repeatedly detected in all but the reference stream. Although microcystin concentrations in the present study did not exceed World Health Organization recreational guidance thresholds, their widespread occurrence demonstrates the need for further investigation of possible in-stream environmental health effects as well as potential impacts on downstream lakes and reservoirs. Environ Toxicol Chem 2016;35:2281-2287. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US Government work and, as such, is in the public domain in the United States of America.
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Affiliation(s)
- Keith A Loftin
- Organic Geochemistry Research Laboratory, Kansas Water Science Center, US Geological Survey, Lawrence, Kansas, USA
| | - Jimmy M Clark
- South Atlantic Water Science Center, US Geological Survey, Columbia, South Carolina, USA
| | - Celeste A Journey
- South Atlantic Water Science Center, US Geological Survey, Columbia, South Carolina, USA
| | - Dana W Kolpin
- Iowa Water Science Center, US Geological Survey, Iowa City, Iowa, USA
| | | | - Daren Carlisle
- National Water Quality Program, US Geological Survey, Lawrence, KS, USA
| | - Paul M Bradley
- South Atlantic Water Science Center, US Geological Survey, Columbia, South Carolina, USA
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Li X, Song J, Lin T, Dixon J, Zhang G, Ye H. Urbanization and health in China, thinking at the national, local and individual levels. Environ Health 2016; 15 Suppl 1:32. [PMID: 26961780 PMCID: PMC4895783 DOI: 10.1186/s12940-016-0104-5] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
BACKGROUND China has the biggest population in the world, and has been experiencing the largest migration in history, and its rapid urbanization has profound and lasting impacts on local and national public health. Under these conditions, a systems understanding on the correlation among urbanization, environmental change and public health and to devise solutions at national, local and individual levels are in urgent need. METHODS In this paper, we provide a comprehensive review of recent studies which have examined the relationship between urbanization, urban environmental changes and human health in China. Based on the review, coupled with a systems understanding, we summarize the challenges and opportunities for promoting the health and wellbeing of the whole nation at national, local, and individual levels. RESULTS Urbanization and urban expansion result in urban environmental changes, as well as residents' lifestyle change, which can lead independently and synergistically to human health problems. China has undergone an epidemiological transition, shifting from infectious to chronic diseases in a much shorter time frame than many other countries. Environmental risk factors, particularly air and water pollution, are a major contributing source of morbidity and mortality in China. Furthermore, aging population, food support system, and disparity of public service between the migrant worker and local residents are important contributions to China's urban health. CONCLUSIONS At the national level, the central government could improve current environmental policies, food safety laws, and make adjustments to the health care system and to demographic policy. At the local level, local government could incorporate healthy life considerations in urban planning procedures, make improvements to the local food supply, and enforce environmental monitoring and management. At the individual level, urban residents can be exposed to education regarding health behaviour choices while being encouraged to take responsibility for their health and to participate in environmental monitoring and management.
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Affiliation(s)
- Xinhu Li
- Key Laboratory of Urban Environment & Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.
| | - Jinchao Song
- Key Laboratory of Urban Environment & Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.
| | - Tao Lin
- Key Laboratory of Urban Environment & Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.
| | - Jane Dixon
- National Centre for Epidemiology and Population Health, the Australian National University, Canberra, ACT 0200, Australia.
| | - Guoqin Zhang
- Key Laboratory of Urban Environment & Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.
| | - Hong Ye
- Key Laboratory of Urban Environment & Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.
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Spatiotemporal Dynamics of Microcystin Variants and Relationships with Environmental Parameters in Lake Taihu, China. Toxins (Basel) 2015; 7:3224-44. [PMID: 26295260 PMCID: PMC4549747 DOI: 10.3390/toxins7083224] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 08/05/2015] [Accepted: 08/11/2015] [Indexed: 01/07/2023] Open
Abstract
Excessive anthropogenically-caused nutrient loading from both external and internal sources has promoted the growth of cyanobacteria in Lake Taihu from 2005 to 2014, suggesting increased production and release of cyanotoxins. In order to explain the spatial distribution and temporal variation of microcystins (MCs), the intracellular concentrations of MCs (MC-LR, -RR and -YR, L, R and Y are abbreviations of leucine, arginine and tyrosine) were monitored monthly from July 2013 to June 2014. Three MC variants are present simultaneously in Lake Taihu; the MC-LR and -RR variants were dominant (accounting for 40% and 39% of the total), followed by MC-YR (21%). However, MC-YR accounted for a higher proportion in colder months, especially in March. The highest concentrations of intracellular MCs were found in July and October when cyanobacteria cell density also reached the maximum. The average concentrations of MC-LR, -RR and -YR in July were 4.69, 4.23 and 2.01 μg/L, respectively. In terms of the entire lake, toxin concentrations in northern parts were significantly higher than the eastern part in summer, when MC concentrations were several times higher than the guideline value by WHO throughout much of Lake Taihu. Results from correlation and redundancy analysis (RDA) showed that total MCs, including all variants, were strongly and positively correlated with cyanobacteria cell density, water temperature, total phosphorus (TP) and pH, whereas each variant had different correlation coefficients with each of the considered environmental variables. MC-RR showed a stronger relationship with temperature, in contrast to MC-YR and -LR. Dissolved inorganic carbon (DIC) showed a negative relationship with each variant, suggesting that rising DIC concentrations may inhibit cyanobacterial growth and thereby reduce MC production in the future.
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21
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Association between changing mortality of digestive tract cancers and water pollution: a case study in the Huai River Basin, China. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2014; 12:214-26. [PMID: 25546281 PMCID: PMC4306858 DOI: 10.3390/ijerph120100214] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 12/16/2014] [Indexed: 11/24/2022]
Abstract
The relationship between the ever-increasing cancer mortality and water pollution is an important public concern in China. This study aimed to explore the association between serious water pollution and increasing digestive cancer mortality in the Huai River Basin (HRB) in China. A series of frequency of serious pollution (FSP) indices including water quality grade (FSPWQG), biochemical oxygen demand (FSPBOD), chemical oxygen demand (FSPCOD), and ammonia nitrogen (FSPAN) were used to characterize the surface water quality between 1997 and 2006. Data on the county-level changing mortality (CM) due to digestive tract cancers between 1975 and 2006 were collected for 14 counties in the study area. Most of investigated counties (eight) with high FSPWQG (>50%) distributed in the northern region of the HRB and had larger CMs of digestive tract cancers. In addition to their similar spatial distribution, significant correlations between FSP indices and CMs were observed by controlling for drinking water safety (DWS), gross domestic product (GDP), and population (POP). Furthermore, the above-mentioned partial correlations were clearly increased when only controlling for GDP and POP. Our study indicated that county-level variations of digestive cancer mortality are remarkably associated with water pollution, and suggested that continuous measures for improving surface water quality and DWS and hygienic interventions should be effectively implemented by local governments.
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