title: Uptake and distribution of chlordecone in radish: different contamination routes in edible roots.
abstract: Chlordecone (CLD) was an organochlorine insecticide mainly used to struggle against banana weevils in the French West Indies. Forbidden since 1993, it has been a long-term contaminant of soils and aquatic environments. Crops growing in contaminated soils lead to human exposure by food consumption. We used radiolabeled [(14)C]-CLD to investigate the contamination ways into radish, a model of edible roots. Radish plants were able to accumulate CLD in both roots (RCF35d 647) and tubers (edible parts, CF35d 6.3). CLD was also translocated to leaves (CF35d 1.7). The contamination of tuber was mainly due to peridermic adsorption or CLD systemic translocation to the pith. TSCF was 3.44×10(-)(3). CLD diffused across periderm to internal tissues. We calculated a mean flux of diffusion J through periderm about 5.71×10(-)(14)gcm(-)(2)s(-)(1). We highlighted different contamination routes of the tuber, (i) adsorption on periderm followed by diffusion of CLD towards underlying tissues, cortex, xylem, and pith (ii) adsorption by roots and translocation by the transpiration stream followed by diffusion from xylem vessels towards inner tissues, pith, and peripheral tissues, cortex and periderm. Concerning chemical risk assessment for other tubers, contamination would depend on various parameters, the thickness of periderm and CLD periderm permeance, the origin of secondary tissues - from cortex and/or pith - , the importance of xylem flow in tuber, and the lipid amount within tuber.
authors.affiliation: Université de Toulouse, INP, UPS, EcoLab (Laboratoire Ecologie Fonctionnelle et Environment), ENSAT, Avenue de l'Agrobiopole, F-31326 Castanet Tolosan, France; CNRS, EcoLab, 31326 Castanet Tolosan, France; INRA, EcoLab, 180 Chemin de Tournefeuille, F-31027 Toulouse, France; ADEME, 20 Avenue du Grésillé, F-49004 Angers, France.
authors.forename: Clarisse
authors.initials: C
authors.lastname: Létondor
authors.affiliation: Université de Toulouse, INP, UPS, EcoLab (Laboratoire Ecologie Fonctionnelle et Environment), ENSAT, Avenue de l'Agrobiopole, F-31326 Castanet Tolosan, France; CNRS, EcoLab, 31326 Castanet Tolosan, France; INRA, EcoLab, 180 Chemin de Tournefeuille, F-31027 Toulouse, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Pascal-Lorber
authors.affiliation: Université de Toulouse, INP, UPS, EcoLab (Laboratoire Ecologie Fonctionnelle et Environment), ENSAT, Avenue de l'Agrobiopole, F-31326 Castanet Tolosan, France; CNRS, EcoLab, 31326 Castanet Tolosan, France; INRA, EcoLab, 180 Chemin de Tournefeuille, F-31027 Toulouse, France. Electronic address: francois.laurent@toulouse.inra.fr.
authors.forename: François
authors.initials: F
authors.lastname: Laurent
mesh_terms: D000327:Adsorption; D007631:Chlordecone / Q000032:analysis* / Q000378:metabolism*; D004781:Environmental Exposure; D004784:Environmental Monitoring; D005506:Food Contamination / Q000032:analysis*; D006801:Humans; D007306:Insecticides / Q000032:analysis / Q000378:metabolism*; D018517:Plant Roots / Q000737:chemistry / Q000378:metabolism; D035281:Plant Tubers / Q000737:chemistry / Q000378:metabolism; D031224:Raphanus / Q000737:chemistry* / Q000378:metabolism*; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism
chemical_list: D007306:Insecticides; D012989:Soil Pollutants; D007631:Chlordecone
keywords: Adsorption; Chlordecone; Periderm diffusion; Radish; Translocation; Uptake