title: Speciation and degradation of triphenyltin in typical paddy fields and its uptake into rice plants.
abstract: Triphenyltin (TPhT) is a biocide used worldwide in agriculture, especially in rice crop farming. The distribution and dissipation of TPhT in rice fields, as well as uptake of TPhT and other phenyltin compounds (monophenyltin, MPhT, and diphenyltin, DPhT) is still unknown at present. In this study, speciation analysis of phenyltin compounds was carried out in soil and water from a rice field where TPhT was applied during rice seeding according to legal application rates in Brazil. The results indicate the degradation of biocide and distribution of tin species into soil and water. To evaluate whether TPhT is taken up by plants, rice plants were exposed to three different TPhT application rates in a controlled mesocosm during 7 weeks. After this period, tin speciation was determined in soil, roots, leaves, and grains of rice. Degradation of TPhT was observed in soil, where DPhT and MPhT were detected. MPhT, DPhT, and TPhT were also detected in the roots of plants exposed to all TPhT application rates. Only TPhT was detected in leaves and at relatively low concentration, suggesting selective transport of TPhT in the xylem, in contrast to DPhT and MPhT. Concentration of phenyltin species in rice grains was lower than the limit of detection, suggesting that rice plants do not have the capability to take up TPhT from soil and transport it to the grains.
authors.affiliation: Departamento de Química, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil.
authors.forename: Fabiane G
authors.initials: FG
authors.lastname: Antes
authors.forename: Eva
authors.initials: E
authors.lastname: Krupp
authors.forename: Erico M M
authors.initials: EM
authors.lastname: Flores
authors.forename: Valderi L
authors.initials: VL
authors.lastname: Dressler
authors.forename: Joerg
authors.initials: J
authors.lastname: Feldmann
mesh_terms: D000383:Agriculture; D004784:Environmental Monitoring; D005618:Fresh Water / Q000737:chemistry; D009947:Organotin Compounds / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D012275:Oryza / Q000378:metabolism*; D018515:Plant Leaves / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism
chemical_list: D009947:Organotin Compounds; D012987:Soil; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; C030665:triphenyltin