Artículo de revista
New biomimetic approach to determine the bioavailability of triclosan in soils and its validation with the wheat plant uptake bioassay
Fecha
2015Registro en:
Chemosphere 119 (2015) 1062–1067
0045-6535
DOI: 10.1016/j.chemosphere.2014.09.030
Autor
Jachero, Lourdes
Ahumada Torres, Aída Inés de Lourdes
Fuentes Pérez, Edwar
Richter Duk, Pablo
Institución
Resumen
A new biomimetic approach for triclosan (TCS) was developed based on the leaching of the analyte from
different biosolid-amended agricultural soils and the subsequent extraction of the leachates, using a
rotating disk sorptive extraction (RDSE) procedure. The leaching equilibrium for TCS was reached at
3 h when the ISO method (ISO/TS 21268-1:2007) was followed.
The concentrations determined by this biomimetic method were compared with the bioavailability of
TCS, determined by its accumulation in the roots of wheat plants grown in the same soil–biosolid
systems.
It was observed that the amount of organic matter in the soil matrix was a determining factor for mobilization
of TCS. An increasing biosolid rate applied to soils resulted in a reduced mobility of TCS because
the high amount of organic matter provided by the biosolid increased the hydrophobic interaction
between TCS and the matrix. Similarly, increasing biosolid concentrations in the soil significantly
decreased the bioavailability of TCS to the wheat plant. Thus, the bioavailability factor in wheat roots
decreased from 0.22 to 0.08 for a soil having a pH of 8.2, when the biosolid rate was increased from
30 to 200 Mg ha 1, respectively.
A significant correlation (R = 0.98) was obtained between TCS concentration in wheat plants and the
proposed biomimetic methodology, indicating that the latter can predict the bioavailability in a time period
as short as 180 min.
The results of this study confirm our previous findings that amending soils with biosolids is beneficial
for immobilizing low polarity contaminants and helps prevent their percolation through the soil profile
and into groundwater.