Toxicity assessment of fresh and weathered petroleum hydrocarbons in contaminated soil- a review.

Soil contamination with total petroleum hydrocarbons (TPH) is widespread throughout the globe due to the massive production of TPH anthropogenically and its occurrence in the soil. TPH is toxic to beneficial soil organisms and humans and thus has become a serious concern among the public. Traditionally TPH toxicity in the soil is estimated based on chemical fractions and a range of bioassays including plants, invertebrates and microorganisms. There is a large inconsistency among ecotoxicology data using these assays due to the nature of TPH and their weathering. Therefore, in this article, we critically reviewed the weathered conditions of TPH, the potential fate in soil and the bioindicators for the assessment of the ecotoxicity. Based on the current research and the state-of-the-art problem, we also highlighted key recommendations for future research scope for the real-world solution of the ecotoxicological studies of hydrocarbons.

Microbial diversity changes with rhizosphere and hydrocarbons in contrasting soils.

In the ecotoxicological assessment of petroleum hydrocarbon-contaminated soil, microbial community profile is important aspect due to their involvement in soil functions. However, soil physicochemical properties and the inhabiting plants could dictate the microbial composition. A question remains unanswered is, how an integrated approach may be utilized to account for various contrasting soil properties, plant types (reference vs. native) and the nature of the hydrocarbon contamination. In this study, we utilized bacterial DNA profiling techniques to investigate the relationship between soil properties, contaminant and plant species. Results identified that Proteobacteria and Actinobacteria were the most abundant bacteria of the 45 phyla identified in the hydrocarbon-contaminated soil. The bulk and rhizosphere microbiome showed that the contaminated soil originally had quite distinct bacterial communities compared to the artificially contaminated soil (mine soil = 95 genera vs. other soils = 2-29 genera). In these cases, not significantly but the native plant slightly increased bacterial diversity and relative abundance in the same soils. Also, within each site, the bacterial community was significantly altered with the hydrocarbon concentration. In this instance, the influence of the contaminant was strong and also with the soil pH and organic matter. These results would significantly contribute to the novel insights on the molecular technique-based hydrocarbon toxicity assessment and the development of the further integrative approach with other microbial community and their metabolic profile in the contaminated sites.

Studies of lipid profile, liver function and kidney function parameters of rat plasma after chronic administration of "Sulavajrini Vatika".

The successful use of Ayurvedic medicines is for many years but there is no guideline for studying the toxicity of these preparations through preclinical or clinical investigations. The present study was conducted to evaluate the effect of conventionally prepared Sulavajrini Vatika (SBB), an Ayurvedic formulation on various biochemical parameters of experimental animals after chronic administration. The animal used was albino rats (Rattus norvegicus: Sprague-Dawley strain) and SBB was administered orally at a single dose of 100 mg kg(-1) b.wt. day(-1), up to 62 days. During the study, forty rats, equally of both sexes, were randomly grouped into four where one male and one female group were used as control and other groups were used as test. Among the lipid components, Triglyceride (TG) was decreased very high significantly in both sexes of animal. The decrease of Total Cholesterol (TC), Very Low Density Lipoprotein (VLDL) and high-density lipoprotein (HDL) were also highly significant. Low Density Lipoprotein (LDL) decreased in all SBB treated group. In the liver function parameters, the total protein and albumin content were increased very high significantly in both sexes of rat. But the bilirubin was decreased insignificantly in male and female rats. Serum Glutamic Pyruvic Transaminase (GPT), Glutamic Oxaloacetic Transaminase (GOT) and Alkaline Phosphatase (ALP) were decreased in all treated animals and it was very high significant. In case of kidney function parameters, creatinine was increased very high significantly but the urea was decreased very high significantly in both sexes of rat. The decrease in uric acid was not significant in none of the sexes of rat. The present study confirms that SBB can be contributory for the complications in diabetics with hyperlipidemia and nephropathy as it lowers most of the lipids components and improves liver function and kidney function parameters.