Abstract Title: | Novel Materials as Binding Agent in Diffusive Gradients in Thin-Films Technique for Mercury Measurement in Freshwater |
Presenter Name: | Siday Marrugo-Madrid |
Company/Institution: | University of Barcelona / Institute of Environmental Assessment and Water Research, IDA-CSIC |
Session: | Mercury Emissions: Monitoring and Analysis |
Co-Authors: | Siday Marrugo-Madrid,Gl?ah Kurt,Carlos Salazar-Camacho,Manuel Salas-Moreno,Harry Gutirrez-Mosquera,Cl udia Font s,Jos Luis Marrugo-Negrete,Sergi D¡ez |
Abstract Information :
Despite the agreement of the Minamata Convention, artisanal and small-scale gold mining (ASGM) continues to take place mainly in remote and difficult-to-access sites, where the application of a convenient method for sampling, preserving and transporting Hg samples is required. In this study, we evaluated the effectiveness of the Diffusive Gradients in Thin Films (DGT) technique for monitoring and quantifying the labile fraction of Hg in Colombian freshwater ecosystems highly impacted by ASGM. Therefore, various types of materials with proven affinity to Hg were evaluated as potential binding layers for novel DGT devices. In laboratory tests, the effects of key DGT parameters (e.g. sorption capacity at different deployments time, ionic strength and pH) were evaluated and the diffusion coefficients were determined. The DGT devices were deployed along the Atrato and Quito rivers, and abandoned mining ponds (Colombia), without statistically significant differences were seen between the concentrations of labile Hg between the sampling points. In the ponds, no significant differences were found in labile Hg related to the abandonment period (p>0.05). This study demonstrates the continuous development of the DGT technique through the use of new and valorized materials with a high affinity for mercury. Funding: Grant 849-2018, University of Cordoba and MINCIENCIAS, Colombia.