Genotoxic endpoints in a Pb-accumulating pea cultivar: insights into Pb 2+ contamination limits

• Published in: Environmental science and pollution research international 2019-11, Vol.26 (31), p.32368
• Main Authors: Rodriguez, Eleazar, Sousa, Márcia, Gomes, Anicia, Azevedo, Raquel, Mariz-Ponte, Nuno, Sario, Sara, Mendes, Rafael José, Santos, Conceição
• Format: Article
• Language: English
• Subjects: Cell Division; Comet Assay; DNA Damage; Environmental Pollutants - chemistry; Environmental Pollutants - metabolism; Lead - chemistry; Lead - metabolism; Mutagens - toxicity; Pisum sativum - chemistry; Pisum sativum - drug effects; Plant Development; Plant Leaves - chemistry; Plant Leaves - metabolism; Seedlings - drug effects
• ISSN: 1614-7499

Lead (Pb) persists among the most hazardous contaminant metals. Pb-induced genotoxic effects remain a matter of debate as they are a major cause of plant growth impairment, but assessing Pb genotoxicity requires the selection of Pb-sensitive genotoxic biomarkers. Seedlings of the ecotoxicological model species Pisum sativum L. were exposed to Pb (≤ 2000 mg L ). Flow cytometry (FCM) revealed that 28 days after, Pb arrested root cell cycle at G but no eu/aneuploidies were found. Comet assay and FCM-clastogenicity assays showed that Pb increased DNA breaks in roots at concentrations as low as 20 mg L . Leaves showed no variation in DNA-ploidy or cell cycle progression but had increased DNA breaks at the highest Pb dose. We conclude that both Comet assay and the full-peak coefficient of variation (FPCV) were the most relevant endpoints of Pb-phytogenotoxicity. Also, the Pb-induced DNA breaks may be related with the arrest at the G -checkpoint. Data will be relevant to better define Pb ecogenotoxicological effects and their measuring tools and may contribute to a regulatory debate of this pollutant limits.