Ecotoxicity and bioremediation potential assessment of soil from oil refinery station area

Abstract

Purpose The aim of the present study was to evaluate the toxicity and biodegradation potential of oil hydrocarbons contaminated soil samples obtained from different depths at an oil refinery station area. An approach involving chemical, microbiological, respirometry and ecotoxicity assessment of soil polluted by oil hydrocarbons was adopted, in order to determine the biodegradability of pollutants and ecotoxicological effects of natural attenuation strategy. Methods The ecotoxicity of soil samples was evaluated using an ostracod test kit and a seed germination test. The results of the phytotoxicity assay were expressed as a percentage of seedling emergence and as the relative yield of fresh and dry biomass compared to control plants. The intrinsic biodegradation potential of the contaminated soil was examined using a Micro-Oxymax respirometer. Intrinsic biodegradation rates were estimated from the slopes of linear regressions curves plotted for cumulative O2 uptake. The obtained values were then entered in the mass balance equation for the stoichiometric reaction of hydrocarbon decomposition and converted per kg of soil per day. Results Although the tested contaminants were biodegradable in the respirometric assay, they were slightly to moderately toxic to plants and extremely toxic to ostracods. The noxious effects raised with the increased concentration of contaminants. The monocotyledonous oat was more tolerant to higher concentrations of oil hydrocarbons than the other test plants, indicating its greater suitability for soil reclamation purposes. Conclusion By assessing phytotoxicity and effect on ostracod mortality and progress of soil self-decontamination process, proper approach of reclamation of demoted area can be provided.

Evaluation of the Toxicity of Wet Wipes Based on the Growth Test with Lepidium sativum L.

“…Biotesting with garden cress is a sensitive method for the study of toxicants and is widely used in practice [6,7,[11][12][13][14].…”

“…Since most of the compounds in the composition of wet wipes are synthetic surfactants, the toxicity of which is known [4], high or extreme toxicity is manifested in wipes impregnated with these compounds. Currently, the need to review the compositions of wet wipes is considered from the angle of protection against microbial spoilage [14], and of rationalizing the physicochemical interactions between the fabric and the preservatives [15]. Attention should also be paid to the issues of the eco-friendliness of these materials [2,16].…”

Long-Term Polyethylene (Bio)Degradation in Landfill: Environmental and Human Health Implications from Comprehensive Analysis

“…The toxicity of the soil samples collected from the MWL was evaluated using the crustacean organism Heterocypris incongruens as the biotest organism. The test proved to be effective in assessing the quality of the environmental soil samples [ 53 ]. This test was employed to assess the ecotoxicity potential of the soil samples from the MWL, including the control soil samples and the reference samples standardized by ISO.…”

Eco-toxicity assessment of fossil fuel tainted soil before phytoremediation trial

“…The eco-toxicity level of crude oil related pollutants in soil is of great concern to stakeholders (Ebulue, 2022). Pollutant's concentrations and the type of pollutants in topsoil can be characterized by analyzing chemically but when it comes to the overall soil quality, chemical analysis alone cannot reflect its true eco-toxicity level (Zawierucha et al, 2022). However, few studies have reported that biological methods seem to be more appropriate in determining the probable risk of pollutants in soil on the environment and its ecology (Tang et al, 2011).…”