Contaminated land clean-up using composted wastes and impacts of VOCs on land

This paper describes experiments that demonstrate the effects and potential for remediation of a former steelworks site in Wales polluted with polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs). Under field conditions, PAH-contaminated soil was composted in-vessel, with or without organic feedstocks, receiving forced aeration for 80 days followed by 4 months maturation. Treatments compared PAH removal in contaminated soil to contaminated soil mixed with three different organic waste mixes after composting and after composts were spread to land. After composting, PAH concentrations declined in all treatments, by up to 38%. Sixteen months after the composts were landspread and vegetation was established, only those containing contaminated soil with organic additions exhibited further PAH removal, by up to 29%. Composting resulted in a decline in the relative concentration of small PAHs, whereas the landspreading-vegetation phase saw a decline in the relative concentration of medium PAHs in two of the three composts exhibiting PAH removal. Under controlled glasshouse conditions, vegetated soil columns of differing depths were exposed to VOCs from beneath. VOC vapour affected both shoot and root growth and soil microbial activity; effects varied with distance from the VOC source. This work demonstrated that on-site remediation of aged PAH-contaminated land can be successfully initiated by in-vessel co-composting followed by land spreading and vegetation, within a practical timeframe.     

Accumulation of lead, cadmium and chromium in some plants cultivated along the bank of river Ribila at Odo-nla area of Ikorodu, Lagos state, Nigeria

Heavy metal in soil samples and in washed and unwashed samples of Telfaria occidentalis (ugwu) and Talinum triangulare (waterleaf) cultivated on the bank of river Ribila in Odo-nla village were determined. The soil was moderately polluted with cadmium when compared with Federal Environmental Protection Agency standards. The difference between the unwashed and washed plant samples revealed that metal pollutants exist as superficial contaminants on the foliage surface which is the edible portion and if the foliage portion is washed thoroughly it may be safe for dietary consumption. There is no doubt that continuous discharge of effluent and gaseous emissions from the industries located in this area and dumping of domestic wastes into the river may lead to higher concentrations of these heavy metals in the soil and in the tissue of the leafy vegetables cultivated on the river bank over time. This can eventually lead to pollution of the soil and the cultivated plants, which are ready source of food for the people and other organisms in the food chain.     

Occurrence of chemical pollutants in major e-waste sites in West Africa and usefulness of cytotoxicity and induction of ethoxyresorufin-O-deethylase (EROD) in determining the effects of some detected brominated flame retardants and e-waste soil-derived extracts

Environmental Science and Pollution Research - We investigated the occurrence of chemical pollutants in major e-waste sites in West Africa and usefulness of cytotoxicity and induction of...     

Periodic characterization of alkyl-naphthalenes in stack gas and ambient air around a medical waste incinerator

Environmental Science and Pollution Research - Due to the subtle occurrence of environmental polycyclic aromatic hydrocarbon (PAHs) pollution from incinerators, it is seldom considered a...     

Dynamics of land use land cover and its impact on carbon stocks in Sub-Saharan Africa: an overview

Environment, Development and Sustainability - Land use land cover change (LULCC) is a global environmental trend that plays a key role in worldwide environmental change and sustainable development....     

Assessment of forest fire vulnerability zones in Missouri,United States of America

Forest fire is one of the major disasters that distresses the terrestrial environment and causes economic disruptions for people and communities in areas prone to forest fire. Information on forest fire risk zones is therefore essential for effective and sound decision-making in forest management. Forest fire risk assessment is a critical part and the most important step in forest management because it enables us to know where the risk is higher in order to minimize threats to life, property and natural resources. This study used a hazard assessment model to assess forest fire risk in Missouri based on several measurable environmental parameters influencing forest fire risk vulnerability. Using the four ecological zones in Missouri as the basis of analysis, three forest risk zones were identified. These were high forest fire risk zones, moderate forest fire risk zone and low forest fire risk zone. Strategies for the mitigation of the hazard of forest fire in the state were also recommended.     

Kolaviron suppresses dysfunctional reproductive axis associated with multi-walled carbon nanotubes exposure in male rats

Reproductive toxicity associated with excessive exposure to multi-walled carbon nanotubes (MWCNTs), which are commonly used in medicine as valuable drug delivery systems, is well documented. Kolaviron, a bioflavonoid isolated from Garcinia kola seeds, elicits numerous health beneficial effects related to its anti-inflammatory, anti-genotoxic activities, anti-apoptotic, and antioxidant properties. However, information on the role of kolaviron in MWCNTs-induced reproductive toxicity is not available in the literature. Herein, we assessed the protective effects of kolaviron on MWCNTs-induced dysfunctional reproductive axis in rats following exposure to MWCNTs (1 mg/kg) and concurrent treatment with kolaviron (50 or 100 mg/kg body weight) for 15 successive days. Results showed that MWCNTs-induced dysfunctional reproductive axis as evidenced by deficits in pituitary and testicular hormones, marker enzymes of testicular function, and sperm functional characteristics were abrogated in rats co-administered with kolaviron. Moreover, co-administration of kolaviron-abated MWCNTs-induced inhibition of antioxidant enzyme activities increases in oxidative stress and inflammatory indices. This is evidenced by diminished levels of tumor necrosis factor-alpha, nitric oxide, lipid peroxidation, reactive oxygen, and nitrogen species as well as reduced activity of myeloperoxidase in testes, epididymis, and hypothalamus of the rats. Biochemical data on the chemoprotection of MWCNTs-induced reproductive toxicity were corroborated by histological findings. Taken together, kolaviron suppressed dysfunctional reproductive axis associated with MWCNTs exposure via abrogation of oxidative stress and inflammation in male rats.

     

Impact of soil types and petroleum effluents on the earthworm, Eudrilus eugeniae

Earthworm, Eudrilus eugeniae, exposed to different concentrations of dump-site soil and petroleum effluents exhibited different morbidity and mortality responses. Lake sediments caused varied fluctuations in weight over a 20 day exposure period. Colour changes and mortality up to 15% were observed in earthworms cultured in 100% lake sediment, while weight loss, coiling and sluggish movement were observed in 50% lake water. The effects of 100% dump-site soils were more pronounced as 40% death, swelling, body lesions, stiffening, coiling and low reproduction were recorded. Earthworms were useful as an organism in testing the toxicity of dump-site soils and effluent from a petroleum industry. Dump-site soils and soils polluted with petroleum effluent reduced populations of earthworms and this could subsequently affect other components of the ecosystems associated with earthworm activities.