Multicorrelation models and uptake factors to estimate extractable metal concentrations from soil and metal in plants in pasturelands fertilized with manure

Environmental risk assessment (ERA) is a useful methodology to estimate the possible adverse effects to human health due to contaminants exposure. In the case of agricultural scenarios, this method requires knowing the concentrations of contaminants in soil solution and vegetation, among other parameters. This study aimed to develop multicorrelation models to estimate metal extractable from soil as a function of total metal concentration in soil and soil properties in a cattle manure application scenario. It also aimed to estimate metal concentrations in plant by soil–plant uptake factors (UF). All the multicorrelation models obtained were significant, ranging R2 values from 0.44 for Cd to 0.92 for Cu. Soil–plant UF were an adequate method for the estimation of metal concentration in plant, since the relationship between the soil–plant UF and the extractable metal concentration from soil was significantly described by a power model, for all the heavy metals.

► When cattle manure is applied as fertilizer, heavy metals may transfer to the soil.
► To evaluate risk, it is crucial to know pollutant content in soil solution and plants.
► Multicorrelation models were developed to estimate extractable metal content from soil.
► Soil–plant uptake factors proved adequate to estimate metal concentration in plant.
► Model application is simple and may result very useful to carry out risk assessments.