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Han X, Gao Y, Yang L, Wei J, Li X, Wang L, Zhang X. Are recyclable plastics eco-friendly? Recycled PVC microplastics show higher toxicity than pristine PVC on Vallisneria natans, regardless of Cadmium. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2024; 273:107024. [PMID: 39003955 DOI: 10.1016/j.aquatox.2024.107024] [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: 03/30/2024] [Revised: 07/09/2024] [Accepted: 07/11/2024] [Indexed: 07/16/2024]
Abstract
As environmental awareness increases, the use of recyclable plastics has risen. However, it is currently unclear whether recycled microplastics (MPs) pose a lesser or greater environmental risk than pristine MPs. Cadmium (Cd), known for its toxicity to most organisms, can bind with MPs and accumulate in sediments. Few studies have explored the environmental risks posed by the coexistence of recycled MPs and pristine MPs with Cd to rooted macrophytes. We investigated the effects of recycled PVC MPs (R-PVC-MPs) and pristine PVC MPs (PVC-MPs) on Vallisneria natans in the presence and absence of Cd. Results showed that at moderate and high Cd levels, R-PVC-MPs reduced plant Cd enrichment. Despite this, the fresh weight of V. natans exposed to R-PVC-MPs was significantly lower than those exposed to PVC-MPs. Furthermore, R-PVC-MPs had more negative impacts on the physiological traits of V. natans than PVC-MPs, as chlorophyll was significantly reduced across all Cd levels. At high Cd levels, both R-PVC-MPs and PVC-MPs caused significantly high oxidative stress, with no significant differences observed. The PCoA plot showed that different MPs cause noticeable variations within the same Cd concentration. The trait network diagrams illustrated strong interactions among traits, with R-PVC-MPs showing the highest complexity. Lower average degree and decreased edge density indicate that traits of plants with R-PVC-MPs addition are more independent of each other. Our findings suggest that recycled PVC MPs pose a greater environmental risk than pristine PVC MPs, offering reference for assessing the risks of recycled plastics in freshwater ecosystems.
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Affiliation(s)
- Xiaohui Han
- Center of Mountain Futures, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China; University of Chinese Academy of Sciences, Beijing, China
| | - Yuxuan Gao
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Li Yang
- College of Resources and Environment, Yunnan Agricultural University, Kunming, China
| | - Junxin Wei
- College of Resources and Environment, Yunnan Agricultural University, Kunming, China
| | - Xi Li
- College of Resources and Environment, Yunnan Agricultural University, Kunming, China
| | - Lei Wang
- College of Resources and Environment, Yunnan Agricultural University, Kunming, China.
| | - Xinhou Zhang
- School of Environment, Nanjing Normal University, Nanjing, China
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Liu X, Guo Y, Li Y, Li Q, Yao L, Yu J, Chen H, Wu K, Qiu D, Wu Z, Zhou Q. Mitigating sediment cadmium contamination through combining PGPR Enterobacter ludwigii with the submerged macrophyte Vallisneria natans. JOURNAL OF HAZARDOUS MATERIALS 2024; 473:134662. [PMID: 38788574 DOI: 10.1016/j.jhazmat.2024.134662] [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: 03/25/2024] [Revised: 05/14/2024] [Accepted: 05/18/2024] [Indexed: 05/26/2024]
Abstract
Sediment cadmium contamination poses risks to aquatic ecosystems. Phytoremediation is an environmentally sustainable method to mitigate cadmium contamination. Submerged macrophytes are affected by cadmium stress, but plant growth-promoting rhizobacteria (PGPR) can restore the health status of submerged macrophytes. Herein, we aimed to reduce sediment cadmium concentration and reveal the mechanism by which the combined application of the PGPR Enterobacter ludwigii and the submerged macrophyte Vallisneria natans mitigates cadmium contamination. Sediment cadmium concentration decreased by 21.59% after submerged macrophytes were planted with PGPR, probably because the PGPR colonized the rhizosphere and roots of the macrophytes. The PGPR induced a 5.09-fold increase in submerged macrophyte biomass and enhanced plant antioxidant response to cadmium stress, as demonstrated by decreases in oxidative product levels (reactive oxygen species and malondialdehyde), which corresponded to shift in rhizosphere metabolism, notably in antioxidant defence systems (i.e., the peroxidation of linoleic acid into 9-hydroperoxy-10E,12Z-octadecadienoic acid) and in some amino acid metabolism pathways (i.e., arginine and proline). Additionally, PGPR mineralized carbon in the sediment to promote submerged macrophyte growth. Overall, PGPR mitigated sediment cadmium accumulation via a synergistic plantmicrobe mechanism. This work revealed the mechanism by which PGPR and submerged macrophytes control cadmium concentration in contaminated sediment.
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Affiliation(s)
- Xiangfen Liu
- Key Laboratory of Lake and Watershed Science for Water Security, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yao Guo
- Key Laboratory of Lake and Watershed Science for Water Security, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Yahua Li
- School of Environmental Studies, China University of Geosciences, Wuhan 430074, China
| | - Qianzheng Li
- Key Laboratory of Lake and Watershed Science for Water Security, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Lu Yao
- Key Laboratory of Lake and Watershed Science for Water Security, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Junqi Yu
- Key Laboratory of Lake and Watershed Science for Water Security, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Han Chen
- Key Laboratory of Lake and Watershed Science for Water Security, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kaixuan Wu
- Key Laboratory of Lake and Watershed Science for Water Security, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Dongru Qiu
- Key Laboratory of Lake and Watershed Science for Water Security, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Zhenbin Wu
- Key Laboratory of Lake and Watershed Science for Water Security, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; School of Environmental Studies, China University of Geosciences, Wuhan 430074, China
| | - Qiaohong Zhou
- Key Laboratory of Lake and Watershed Science for Water Security, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
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Zhou J, Liu X, Jiang H, Li X, Li W, Cao Y. Antidote or Trojan horse for submerged macrophytes: Role of microplastics in copper toxicity in aquatic environments. WATER RESEARCH 2022; 216:118354. [PMID: 35358874 DOI: 10.1016/j.watres.2022.118354] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 02/17/2022] [Accepted: 03/21/2022] [Indexed: 05/23/2023]
Abstract
Due to their unique surface structures and physicochemical properties, microplastics (MPs) can adsorb other contaminants, thus impacting their toxicity and fate in aquatic ecosystems. In the present study, the adsorption and transportation of copper ions (Cu2+) in polyethylene (PE, 5 and 150 μm) and their combined effects on four submerged macrophyte species were assessed. Results demonstrated that the addition of PE reduced the Cu2+ concentration in copper sulfate (CuSO4) solution and the adsorption of Cu2+ in PE (10 mg/L) increased with CuSO4 concentration (100-600 μmol/L). PE alone exhibited no inhibitory effects on macrophytes, while Cu2+ showed fatal toxicity toward the macrophytes. However, the combination of PE and Cu2+ showed lower inhibitory effects on macrophytes and the toxicity attenuation varied among species. Additionally, PE may act as a carrier (like a Trojan horse) for the environmental transfer of Cu2+, thereby hosting Cu2+ toxicity against macrophytes in the imported environment. Our findings indicate that PE acts as both an antidote to and carrier of Cu2+ toxicity in macrophytes. This study should help in clarifying the combined effects and risk assessments of MPs and heavy metals in future studies.
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Affiliation(s)
- Jingzhe Zhou
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaoning Liu
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China.
| | - Hongsheng Jiang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China
| | - Xingjian Li
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China
| | - Wei Li
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China; Center for Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan 430074, China
| | - Yu Cao
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China.
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Wang L, Gao Y, Jiang W, Chen J, Chen Y, Zhang X, Wang G. Microplastics with cadmium inhibit the growth of Vallisneria natans (Lour.) Hara rather than reduce cadmium toxicity. CHEMOSPHERE 2021; 266:128979. [PMID: 33218728 DOI: 10.1016/j.chemosphere.2020.128979] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 11/11/2020] [Accepted: 11/12/2020] [Indexed: 05/07/2023]
Abstract
Microplastics and heavy metals are discharged into a freshwater environment either directly or via surface runoff and are largely deposited in sediments, posing risks to aquatic organisms. Few studies have thus far been devoted to the interaction of microplastics and heavy metals in sediments. Whether microplastics can affect the toxicity and accumulation of heavy metals in submerged macrophytes remains unclear. We evaluated the effects of polyvinyl chloride microplastics (PVC-MPs) and cadmium (Cd) exposure levels (0, 5, 15, and 25 mg) on Vallisneria natans (Lour.) Hara grown in sediment in a microcosm experiment for 14 d. In this study, PVC-MPs decreased the fresh weights of V. natans in the absence of Cd and markedly reduced the fresh weights at 5 and 15 mg Cd exposure levels. Moreover, PVC-MPs substantially increased the malondialdehyde (MDA) content of V. natans leaves at a Cd exposure of 25 mg. However, the PVC-MPs neither reduced the Cd concentration nor independently increased the antioxidant enzyme activities of the plants. These findings indicate that microplastics can independently, or jointly with a Cd contaminant, inhibit the growth of submerged macrophytes rather than reduce Cd toxicity. To our knowledge, this study is the first to evaluate the effects of microplastics and Cd exposure in sediments on the growth and physiological traits of submerged macrophytes, which could provide important implications for the interaction and future risk assessment of microplastics and heavy metals in sediments of freshwater ecosystems.
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Affiliation(s)
- Lei Wang
- School of Environment, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing, 210023, China
| | - Yuxuan Gao
- School of Environment, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing, 210023, China
| | - Wei Jiang
- School of Environment, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing, 210023, China
| | - Junxiu Chen
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Yanshan Chen
- School of Environment, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing, 210023, China
| | - Xinhou Zhang
- School of Environment, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing, 210023, China.
| | - Guoxiang Wang
- School of Environment, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing, 210023, China.
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Sharma KV, Sarvalingam BK, Marigoudar SR. A review of mesocosm experiments on heavy metals in marine environment and related issues of emerging concerns. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:1304-1316. [PMID: 33079346 DOI: 10.1007/s11356-020-11121-3] [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: 02/07/2020] [Accepted: 10/04/2020] [Indexed: 06/11/2023]
Abstract
Mesocosms are real-world environmental science tools for bridging the gap between laboratory-scale experiments and actual habitat studies on ecosystem complexities. These experiments are increasingly being applied in understanding the complex impacts of heavy metals, ocean acidification, global warming, and oil spills. The insights of the present review indicate how metals and metal-bound activities impact on various aspects of ecological complexities like prey predator cues, growth, embryonic development, and reproduction. Plankton and benthos are used more often over fish and microbes owing to their smaller size, faster reproduction, amenability, and repeatability during mesocosm experiments. The results of ocean acidification reveal calcification of plankton, corals, alteration of pelagic structures, and plankton blooms. The subtle effect of oil spills is amplified on sediment microorganisms, primary producers, and crustaceans. An overview of the mesocosm designs over the years indicates that gradual changes have evolved in the type, size, design, composition, parameters, methodology employed, and the outputs obtained. Most of the pelagic and benthic mesocosm designs involve consideration of interactions within the water columns, between water and sediments, trophic levels, and nutrient rivalry. Mesocosm structures are built considering physical processes (tidal currents, turbulence, inner cycling of nutrients, thermal stratification, and mixing), biological complexities (population, community, and ecosystem) using appropriate filling containers, and sampling facilities that employ inert materials. The principle of design is easy transportation, mooring, deployment, and free floating structures besides addressing the unique ecosystem-based science problems. The evolution of the mesocosm tools helps in understanding further advancement of techniques and their applications in marine ecosystems.
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Affiliation(s)
- Krishna Venkatarama Sharma
- National Centre for Coastal Research, Ministry of Earth Sciences, Government of India, NIOT Campus, Pallikaranai, Chennai, 600 100, India
| | - Barath Kumar Sarvalingam
- National Centre for Coastal Research, Ministry of Earth Sciences, Government of India, NIOT Campus, Pallikaranai, Chennai, 600 100, India
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Wang L, Gao Y, Wang X, Qin Z, Liu B, Zhang X, Wang G. Warming enhances the cadmium toxicity on macrophyte Myriophyllum aquaticum (Vell.) Verd. seedlings. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 268:115912. [PMID: 33187844 DOI: 10.1016/j.envpol.2020.115912] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 09/27/2020] [Accepted: 10/19/2020] [Indexed: 06/11/2023]
Abstract
Due to a close contact with water column, submerged macrophytes are easily disturbed by environment change in freshwater ecosystems, especially at the seedling stage. In recent decades, freshwater ecosystems have been subject to severe cadmium (Cd) pollution, which can cause toxic effects on the growth of submerged macrophytes. Moreover, the temperature rise resulting from climate warming and water level decline may further aggravate such effect, especially in shallow lakes. Here, we investigated the independent and interaction effects of Cd exposure levels (0, 0.5, 1, and 2.5 mg L-1) and temperature (15, 25, and 30 °C) on morphological and physiological traits of Myriophyllum aquaticum (Vell.) Verd. Seedlings generated from propagules and seeds. The temperature rise and Cd exposure generally resulted in a significant increase of Cd concentrations and antioxidant enzyme activities in leaves, as well as a decrease of chlorophyll a and b concentrations. The number and length of leaves generated from propagules always show a downward trend with the increase of Cd exposure, regardless of the temperature. Moreover, the lowest leaf number and length always occurred at high temperature (i.e. 30 °C) when the Cd exposure level increased to 1 and 2.5 mg L-1. For the seedlings generated from seeds, the temperature rise caused an increase of leaf emergence rate under low Cd exposure levels, but resulted in a significant decrease with the Cd exposure level. This study indicates the negative effects of Cd exposure and temperature rise on submerged macrophytes at the seedling stage, and highlights that temperature rise would enhance Cd toxicity.
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Affiliation(s)
- Lei Wang
- School of Environment, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing, 210023, China
| | - Yuxuan Gao
- School of Environment, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing, 210023, China
| | - Xuan Wang
- School of Environment, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing, 210023, China
| | - Zhangyi Qin
- School of Environment, Nanjing Normal University, Nanjing, 210023, China
| | - Baogui Liu
- School of Environment, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing, 210023, China
| | - Xinhou Zhang
- School of Environment, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing, 210023, China
| | - Guoxiang Wang
- School of Environment, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing, 210023, China.
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Qian Y, Cheng C, Drouillard K, Zhu Q, Feng H, He S, Fang Y, Qiao S, Kolenčíka M, Chang X. Bioaccumulation and growth characteristics of Vallisneria natans (Lour.) Hara after chronic exposure to metal-contaminated sediments. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:20510-20519. [PMID: 31102223 DOI: 10.1007/s11356-019-05347-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Revised: 04/29/2019] [Accepted: 05/01/2019] [Indexed: 06/09/2023]
Abstract
Metal-contaminated sediments in lakes is a global concern that poses toxicological risk to aquatic organisms. This study performed bioassays using the submerged macrophyte, Vallisneria natans (Lour.) Hara, exposed to contaminated sediments collected from five locations in Dianchi Lake, Yunnan, China. Among the sediments collected, Igeo showed enrichment of As and Cd in Dianchi Lake sediments. In spite of enriched toxic metals at some locations, laboratory bioassays found no significant difference in leaf biomass or leaf photosynthesis rate between the sites. Root biomass and root activity showed significant differences between locations and were negatively correlated with the concentration of As, Cd, Hg, and Pb in sediment but not related to Cr. The above correlations were strongest for Hg and As, respectively. Accumulation of Cd and Pb to leaves of bioassay plants was observed, but this was not evident for As and Cr. Overall, the results indicate that V. natans can be used as a bioassay organism and measures of root toxicity are sensitive to metal concentrations present in Dianchi Lake sediments. Furthermore, the study species holds promise for use as a biomonitor of Cd and Pb sediment metal content.
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Affiliation(s)
- Yu Qian
- School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650091, Yunnan, China
| | - Changlei Cheng
- Analysis and Measurements Center of Yunnan Provincial Non-ferrous Geology Bureau, Kunming, 650051, Yunnan, China
| | - Ken Drouillard
- Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON, N9B3P4, Canada
| | - Qingzhi Zhu
- School of Marine and Atmospheric Science, State University of New York, Stony Brook, NY, 11794, USA
| | - Huan Feng
- Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ, 07043, USA
| | - Shuzhuang He
- School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650091, Yunnan, China
| | - Yuhong Fang
- School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650091, Yunnan, China
| | - Shinan Qiao
- School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650091, Yunnan, China
| | - Marek Kolenčíka
- Department of Soil Science and Geology, Faculty of Agrobiology and Food Resources, Slovak University of Agriculture in Nitra, 94976, Nitra, Slovak Republic
| | - Xuexiu Chang
- School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650091, Yunnan, China.
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Chen M, Gao Y, Bian X, Feng J, Ma W, Zhu L. Predicting the survival of zebrafish larvae exposed to fluctuating pulses of lead and cadmium. CHEMOSPHERE 2019; 223:599-607. [PMID: 30798055 DOI: 10.1016/j.chemosphere.2019.02.102] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 02/15/2019] [Accepted: 02/15/2019] [Indexed: 06/09/2023]
Abstract
Aquatic organisms are often exposed to time-varied concentrations of contaminants due to pulsed inputs in natural water. Traditional toxicology experiments are usually carried out in a constant exposure pattern, which is inconsistent with the actual environment. In this study, a refined toxicokinetic-toxicodynamic (TK-TD) model was used to study the toxic effects of Pb and Cd on zebrafish larvae under three pulse exposures with 2, 4, and 6 h, respectively. The parameter sensitivity analysis showed that JM, max had the greatest impact on the output of the model. Cd or Pb pulse exposure resulted in less death than constant exposure at the same time-weighted average (TWA) concentrations. Survival fraction in larvae under 6 h interval between two pulses of Pb or Cd was larger than that under 2 h and 4 h interval. Toxicity under constant exposure of Cd or Pb was greater than that under 2, 4, and 6 h interval pulse exposure because the cumulative Cd or Pb concentration in the body under constant exposure was greater than that under pulse exposure. The results also showed that the stochastic death (SD) model was more suitable than the individual tolerance (IT) model for predicting the survival fraction of larvae under pulse exposure to Pb and Cd, which was indicated by higher R2 (0.670-0.940) in SD model than that (0.588-0.861) in IT model. Our model provides approaches for laboratory toxicity testing and modeling approaches for addressing the toxicity of heavy metal pulsed exposure.
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Affiliation(s)
- Min Chen
- Key Laboratory of Pollution Process and Environmental Criteria of Ministry of Education and Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | - Yongfei Gao
- Key Laboratory of Pollution Process and Environmental Criteria of Ministry of Education and Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | - Xiaoxue Bian
- Key Laboratory of Pollution Process and Environmental Criteria of Ministry of Education and Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | - Jianfeng Feng
- Key Laboratory of Pollution Process and Environmental Criteria of Ministry of Education and Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China.
| | - Weiqi Ma
- Key Laboratory of Pollution Process and Environmental Criteria of Ministry of Education and Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | - Lin Zhu
- Key Laboratory of Pollution Process and Environmental Criteria of Ministry of Education and Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China.
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Cao Y, Liu H, Sun J, Liu Y, Jiang HS, Wang W, Li W. Responses of propagule germination and sexual reproduction of submerged macrophytes exposed to cadmium. CHEMOSPHERE 2019; 219:436-443. [PMID: 30551110 DOI: 10.1016/j.chemosphere.2018.12.056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Revised: 11/23/2018] [Accepted: 12/07/2018] [Indexed: 06/09/2023]
Abstract
Submerged macrophytes are considered the main primary producers in shallow lakes. Recently, they have experienced a decline due to increasing environmental impacts, e.g., excessive heavy metal loads. Compared to extensive studies on vegetative growth, reports on effects of heavy metals on propagule germination and reproduction remain scarce. In this study, three experiments were conducted to investigate the effects of cadmium (Cd) on the propagule germination and sexual reproduction of submerged macrophytes. In Experiment I, six Cd concentrations were used (0, 0.05, 0.5, 1, 2.5, and 5 mg L-1), with seed germination found to be marginally affected by Cd treatment. In Experiment II, Cd exposure (5 d) at the six Cd concentrations was performed 15, 30, 60, 90, and 120 d prior to the designated germination date for turions/tubers. The Vallisneria spinulosa tubers did not germinate at ≥ 2.5 mg Cd L-1 when exposed to Cd 90 and 120 d prior to germination, whereas the Potamogeton crispus turions remained viable but with a low germination rate at ≥ 2.5 mg Cd L-1. In Experiment III, with an increase from 0 to 0.5 Cd mg L-1, the fruit weight of Ottelia alismoides and V. spinulosa decreased, whereas the fruit number increased for O. alismoides but not for V. spinulosa. Furthermore, the phenology of sexual reproduction for both species advanced under Cd exposure. In summary, Cd exposure affected the germination of asexual propagules and sexual reproduction of submerged macrophytes, with seeds found to be tolerant of Cd treatment up to 5 mg L-1.
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Affiliation(s)
- Yu Cao
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China; Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Hui Liu
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China; Key Laboratory of Ecological Impacts of Hydraulic-Projects and Restoration of Aquatic Ecosystem of Ministry of Water Resources, Institute of Hydroecology, Ministry of Water Resources and Chinese Academy of Sciences, Wuhan, 430079, China
| | - Junyao Sun
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China; Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Yang Liu
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China; Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Hong Sheng Jiang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China; Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Wei Wang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China; Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Wei Li
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China; Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China.
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