title: Toxicity assessment of boron (B) by Lemna minor L. and Lemna gibba L. and their possible use as model plants for ecological risk assessment of aquatic ecosystems with boron pollution.
abstract: As many of the metalloid-based pollutants, the boron (B) toxicity issues have aroused more and more global attentions, especially concerning drinking water sources which flow through boron-rich areas. Therefore, feasible and innovative approaches are required in order to assess B toxicity in aquatic ecosystems. In this study, the toxic effects of B on Lemna minor L. and Lemna gibba L. were investigated using various endpoints including number of fronds, growth rates, dry biomass and antioxidants enzymatic activities. Lemna species were exposed to B concentrations of 2 (control), 4, 8, 16, 32, 64 and 128 mg L(-1) for a test period of 7 days. The results demonstrated that plant growth was significantly reduced when the B concentration reached 16 mg L(-1). Furthermore, our results also concluded that among the antioxidative enzymes, SOD, APX and GPX can serve as important biomarkers for B-rich environment. The present results suggested that L. minor and L. gibba are very useful model plants for phytoremediation of low-B contaminated wastewater and they are also suitable options for B biomonitoring due to high phototoxic sensitivity against B. In this respect, the scientific insight of the present study is to fill the gaps in the research about the use of L. minor and L. gibba in ecotoxicological research associated with B toxicity.
authors.affiliation: Faculty of Science, Department of Biology, Anadolu University, Eskişehir, Turkey.
authors.forename: Nurcan
authors.initials: N
authors.lastname: Gür
authors.affiliation: Faculty of Science and Letters, Department of Biology, Aksaray University, Aksaray, Turkey.
authors.forename: Onur Can
authors.initials: OC
authors.lastname: Türker
authors.affiliation: Faculty of Science, Department of Biology, Anadolu University, Eskişehir, Turkey. Electronic address: hbocuk@anadolu.edu.tr.
authors.forename: Harun
authors.initials: H
authors.lastname: Böcük
mesh_terms: D000975:Antioxidants / Q000494:pharmacology; D029064:Araceae / Q000187:drug effects* / Q000254:growth & development; D001673:Biodegradation, Environmental; D015415:Biomarkers / Q000032:analysis; D018533:Biomass; D001895:Boron / Q000032:analysis / Q000494:pharmacology / Q000633:toxicity*; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods*; D010088:Oxidoreductases / Q000032:analysis; D018570:Risk Assessment; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D014874:Water Pollutants, Chemical; D010088:Oxidoreductases; D001895:Boron
keywords: Antioxidative enzymes; Biomonitoring; Boron toxicity; Duckweeds; Phytoremediation