title: Analysis of the use of microcystin-contaminated water in the growth and nutritional quality of the root-vegetable, Daucus carota.
abstract: Toxic cyanobacterial blooms are often observed in freshwaters and may reflect the increased eutrophication of these environments and alterations in climate. Cyanotoxins, such as microcystins (MCs), are an effective threat to many life forms, ranging from plants to humans. Despite the research conducted to date on cyanotoxins, the risks associated to the use of contaminated water in agriculture require further elucidation. To tackle this aim, a research was conducted with the root-vegetable Daucus carota. The specific aims of this work were the following: (i) to evaluate the effects of MC-LR on the plant growth and photosynthesis; (ii) to evaluate the nutritional quality of carrot roots; and (iii) to measure bioaccumulation. To this purpose, young carrots were grown in soil during 1 month in natural conditions and exposed to Mycrocystis aeruginosa aqueous extracts containing environmentally realistic concentrations of MC-LR (10 and 50 MC-LR μg/L). The results showed that MC-LR may decrease root growth after 28 days of exposure to 50 μg/L and increase photosynthetic efficiency. We also observed changes in mineral and vitamin content in carrots as a result of the exposure to contaminated water. Moreover, MC-LR was detected in carrot roots by ELISA at very low concentration 5.23 ± 0.47 ng MC eq./g FW. The soil retained 52.7 % of the toxin potentially available for plants. This result could be attributed to MC-LR adsorption by soil particles or due to microbial degradation of the toxin. We conclude that the prolonged use of MC-LR-contaminated water may affect crop growth, alter the nutritional value of vegetable products, and potentiate contamination.
authors.affiliation: Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Rua dos Bragas 289, P 4050-123, Porto, Portugal.
authors.forename: J
authors.initials: J
authors.lastname: Machado
authors.affiliation: Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Rua dos Bragas 289, P 4050-123, Porto, Portugal.
authors.forename: J
authors.initials: J
authors.lastname: Azevedo
authors.affiliation: Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Rua dos Bragas 289, P 4050-123, Porto, Portugal.|Department of Environmental Health of School of Allied Health Technologies, and CISA/Research Center in Environment and Health, Polytechnic Institute of Porto, Rua de Valente Perfeito, 322, P 440-330, Gaia, Portugal.
authors.forename: M
authors.initials: M
authors.lastname: Freitas
authors.affiliation: REQUIMTE, Department of Chemical Sciences, Laboratory of Applied Chemistry, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira 228, P 4050-313, Porto, Portugal.|Department of Environmental Health of School of Allied Health Technologies, and CISA/Research Center in Environment and Health, Polytechnic Institute of Porto, Rua de Valente Perfeito, 322, P 440-330, Gaia, Portugal.
authors.forename: E
authors.initials: E
authors.lastname: Pinto
authors.affiliation: REQUIMTE, Department of Chemical Sciences, Laboratory of Applied Chemistry, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira 228, P 4050-313, Porto, Portugal.
authors.forename: A
authors.initials: A
authors.lastname: Almeida
authors.affiliation: Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Rua dos Bragas 289, P 4050-123, Porto, Portugal.|Department of Biology, Faculty of Sciences, University of Porto, Rua do Campo Alegre, P 4069-007, Porto, Portugal.
authors.forename: V
authors.initials: V
authors.lastname: Vasconcelos
authors.affiliation: Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Rua dos Bragas 289, P 4050-123, Porto, Portugal. acampos@ciimar.up.pt.
authors.forename: A
authors.initials: A
authors.lastname: Campos
mesh_terms: D018552:Daucus carota / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D005068:Eutrophication; D052998:Microcystins / Q000633:toxicity*; D008903:Minerals / Q000378:metabolism; D009753:Nutritive Value / Q000187:drug effects*; D010788:Photosynthesis / Q000187:drug effects; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D014675:Vegetables / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D014815:Vitamins / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D014876:Water Pollution / Q000009:adverse effects
chemical_list: D052998:Microcystins; D008903:Minerals; D014815:Vitamins; D014874:Water Pollutants, Chemical; C078588:microcystin
keywords: Cyanobacteria; Daucus carota; Growth; Irrigation water; Microcystin-LR; Minerals; Vitamins