Phytoremediation, biostimulation and toxicity in diesel-polluted agricultural soils using <i>Gypsophila paniculata</i> and spent <i>Pleurotus</i> spp. substrate

In Mexico, oil spills are primarily caused by fuel theft. These incidents have led to the degradation of agricultural soils, with adverse effects on the environment, human health, and the economic development of affected regions. Consequently, biotechnological decontamination techniques have emerged as a promising solution for the restoration of these sites. This study aimed to evaluate the phytoremediation of diesel-contaminated agricultural soils using <i>Gypsophila paniculata</i> and spent <i>Pleurotus</i> spp. substrate as a biostimulant. Additionally, the potential genetic and cellular damage caused by the contaminants present in the soil was assessed before and after the application of biological decontamination treatments. The greenhouse experiment lasted 50 days. Morphological variables of the plants and the total petroleum hydrocarbons (TPH) (mg/kg) were measured, alongside soil toxicity, which was assessed by evaluating the mitotic index (%) and micronucleus frequency (%) in <i>Vicia faba</i> cells. Plants grown with the biostimulant exhibited enhanced morphological characteristics, while the bioremediation treatments achieved diesel removal rates ranging from 29.4% to 46.1%. However, potential genotoxic and cytotoxic effects were observed across all treatments. This research proposes the use of a short-cycle ornamental flower in biostimulation treatments to remove diesel from agricultural soils without hindering their productivity. However, genetic and cellular damage potentially caused by the presence of hydrocarbons is still observed, even after the phytoremediation process. There are few studies on bioremediation in real hydrocarbon-contaminated agricultural soils that utilize regional resources for soil recovery and assess potential toxicity. The findings of this research will enable future studies on bioremediation strategies that take health risks into account.