## 3 Results
### Toxicological Analysis  
Toxicological tests carried out on initial soil samples and after remediation treatments in the studied systems allowed for the assessment of the impact of changes in the concentrations of petroleum substances on soil biocenosis. Each of the toxicological tests performed showed the greatest decrease in soil toxicity in systems in which phytoremediation (_Echinacea purpurea_) was carried out supported by bioaugmentation with the B2 microbial consortium with the addition of \(\gamma\)-PGA. Phytoremediation supported by vaccina  
Figure 6: PAH content of _Echinacea purpurea_ roots after 3 and 6 months of phytoremediation process aided by bioaugmentation in the tested systems. Figure 7: PAH content of _Echinacea purpurea_ shoots after 3 and 6 months of phytoremediation process aided by bioaugmentation in the tested systems. tion with the B1 microbial consortium with \(\gamma\)-PGA turned out to be slightly less effective. By far the smallest decrease in soil toxicity was observed in non-inoculated systems and in systems inoculated with \(\gamma\)-PGA alone. The obtained results of toxicological tests were consistent with the results of chromatographic analyses, which confirms the assumption that soil toxicity largely depends on the amount of TPHs and PAHs in the soil. A summary of the results of all toxicological tests performed for Soil DW and Soil OS subjected to the bioremediation process in the tested systems is presented in Figures 8 and 9. Manufacturer-level toxicity tests carried out using the Phytotoxkit test took into account two toxicity assessment criteria: inhibition of root growth and inhibition of germi  
Figure 8: Summary of the results of toxicological tests of drilling waste soil (Soil DW) subjected to the purification process in the analyzed systems (\(n=3,p<0.05\)). Figure 9: Summary of the results of toxicological tests of oil spill soil (Soil OS) subjected to the purification process in the analyzed systems (\(n=3,p<0.05\)). nation. Taking into account the criterion of root growth inhibition, the toxicity expressed in the TU toxicity unit was determined for Soil DW and Soil OS initial soils at the levels of 12.2 and 9.8 (_Lapidum sativum_), 10.5 and 8.5 (_Sorgum saccharatum_), and 12.3 and 9.2 (_Sinapis alba_), respectively. The degrees of toxicity of Soil DW after bioremediation in the tested systems ranged from 10.5 to 4 (_Lapidum sativum_), 9.8 to 3.6 (_Sorgum saccharatum_) and from 10.3 to 3.3 (_Sinapis alba_). The toxicity of Soil OS after 6 months of purification, depending on the tested system, was in the range of 9.8-3.7 (_Lapidum sativum_), 7.8-3.3 (_Sorgum saccharatum_) and 9.5-2.9 (_Sinapis alba_). For the second parameter tested (germination inhibition), the TU values calculated for the tested plants in the initial soil samples were in the range of 9.3-7.6 (Soil DW) and 6.8-5.3 (Soil OS). As a result of the remediation procedures, a reduction in the degree of soil toxicity was achieved, with values ranging from 8.8 to 2.6 (Soil DW) and from 6.8 to 2.6 (Soil OS). Soil toxicity at the consumer level was determined on the basis of the Ostracodtoxkit toxicological test, which showed that the use of phytoremediation supported by bioaugmentation with the B2 microbial consortium with \(\gamma\)-PGA caused the greatest decrease in the toxicity of soils polluted with petroleum hydrocarbons compared to _Heterocypris incongrurues_. In the soil taken from the excavated pit area (Soil DW), the TU value decreased from 11.2 to 4.2 (Soil DW-5), and in the soil from the oil spill area (Soil OS), the TU value decreased from 10.9 to 3.6. The values of soil toxicity degrees after completion of phytoremediation supported by bioaugmentation with microbial consortium B1 with \(\gamma\)-PGA were 5.2 (Soil DW-4) and 4.2 (Soil OS-4). The highest toxicity values after remediation treatments were recorded in non-inoculated soils, at 10.2 (Soil DW-1) and 9.9 (Soil OS-1).