Short-term arsenic mobilization, labilization, and microbiological aspects after gasoline and diesel addition in tropical soils

Luko-Sulato, Karen [UNESP]; Sulato, Everton Tiago [UNESP]; Podsclan, Caroline Barradas [UNESP]; de Souza de Oliveira, Lucia Maria [UNESP]; Kabuki, Lauren Nozomi Marques [UNESP]; Rosolen, Vania [UNESP]; Menegário, Amauri Antonio [UNESP]

Short-term arsenic mobilization, labilization, and microbiological aspects after gasoline and diesel addition in tropical soils

Data

2023-06-01

Autores

Luko-Sulato, Karen

Sulato, Everton Tiago

Podsclan, Caroline Barradas

de Souza de Oliveira, Lucia Maria

Kabuki, Lauren Nozomi Marques

Rosolen, Vania

Menegário, Amauri Antonio

Tipo

Artigo

Resumo

The effect of the presence of gasoline and diesel on the speciation and mobility of inorganic arsenic species in tropical topsoils was investigated. Topsoil samples (n = 25) were contaminated with gasoline and diesel (500 mg kg−1) in laboratory and were incubated under unsaturated conditions and regular aeration for 21 days. Speciation analysis and chemical fractionation were performed in the pore water from control, gasoline, and diesel-contaminated soil samples. Arsenic concentrations were compared to microbiological parameters (microbial metabolic quotient and soil basal breathing) and the presence of ArsM-harboring bacteria. The spike of gasoline and diesel to the topsoils increased pore water As3+ (H3AsO3) concentration. Arsenic mobilization was lower compared to previously reported data for other sources of organic matter (biochar, litter, and a mixture of sphagnum peat moss and composted poultry manure). However, gasoline or diesel addition mobilized As fractions that were adsorbed to the solid phase, in approximately 60% of the soils. Methylation presented an important role in the As3+ regulation in control soils, which was no longer observed after gasoline or diesel addition. The quantification of the labile fractions sampled by the diffusive gradients in thin films technique showed that the increased As concentration in the gasoline or diesel-contaminated soils mostly included inert species. Dissolved organic carbon content seems to be an important control mechanism of the labile As concentration. The increase in As mobility seems to pose a more concerning scenario due to As leaching than to plant uptake.