An investigation into the pollution of stormwater runoff from automobile workshops in Nigeria was performed. Also, multivariate regression was used to predict the pH, oil, and grease (O&G) as well as the electrical conductivity (EC) in relation to the characteristics of the solids and metals pollutants of the untreated automobile workshop stormwater. The results indicated that automobile workshops contributed notable amounts of pollutants to stormwater runoff. Results were compared with Nigerian and USEPA standards. It was found that most of the parameters had mean value ranges far greater than standard limits. The multivariate regression showed variations in the results obtained from different automobile workshops. These variations could be due to the influence of factors such as the volume of automobile servicing activities and the waste generated from these activities that flow in the stormwater runoff. However, the bulk of the EC and pH of the stormwater were associated with the concentrations of the total dissolved solids and copper while the bulk of the O&G concentration was associated with the concentrations of lead and cadmium. It is recommended to treat automobile workshop stormwater to prevent detrimental effects in aquatic systems. Future research is aimed at modeling such treatment using multivariate regression techniques is warranted.

Salicylaldehyde (SA) is used in numerous biological, pharmaceutical, and industrial applications. Releasing effluents from these industries contaminates water. So the degradation of salicylaldehyde is necessitated. The electrochemical degradation of salicylaldehyde in buffered media was studied using the eco-friendly cyclic voltammetry (CV) technique on a platinum electrode at different scan rates. Kinetic and electrochemical parameters were evaluated for the reaction such as standard heterogeneous rate constant (k0,2.468×103 s-1 ), anodic electron transfer rate constant (kox,2.507×103 s-1), electron transfer coefficient of reaction (α,0.673), and formal potential (E0, 1.0937) under the influence of scan rate. The nature of the reaction is found to be diffusion controlled. The concentration study in the range of1 mM to 4 mM was calibrated. The limit of detection and the limit of quantification were calculated to be 0.0031 mM and 0.0103 mM respectively.

Incubation under controlled laboratory conditions were performed to assess the toxic effects of two plastic derived chemicals, bisphenol A (BPA) and di-(2-ethylhexyl) phthalate (DEHP), on the growth, photosynthetic efficiency and photosynthetic activity of the cosmopolitan diatom Chaetoceros decipiens-lorenzianus. Non-axenic diatom cells were exposed to concentrations of BPA and DEHP (separately and in mixture), mimicking concentrations observed in contaminated marine ecosystems, for seven days. Upon short-term exposure (i.e., during the first 48 h), BPA and DEHP induced a slight but significant stimulation of biomass and photosynthetic activity relative to the control, whereas, no significant impact was observed on the photosynthetic efficiency. Nevertheless, this pattern was transient. The stimulation was followed by a return to control conditions for all treatments at the end of incubation. These results showed that the cosmopolitan diatom Chaetoceros was not impacted by representative in situ concentrations of plastic derivatives, thus confirming its ability to thrive in coastal anthropogenic environments.

The little information available on fuel consumption and emissions by high seas tuna fisheries indicates that the global tuna fleet may have consumed about 2.5 Mt of fuel in 2009, resulting in the production of about 9 Mt of CO2-equivalent greenhouse gases (GHGs), i.e., about 4.5–5% of the global fishing fleet emissions. We developed a model of annual fuel consumption for the large-scale purse seiners operating in the western Indian Ocean as a function of fishing effort, strategy, and vessel characteristics based on an original and unique data set of more than 4300 bunkering operations that spanned the period 2013–2019. We used the model to estimate the total fuel consumption and associated GHG and SO2 emissions of the Indian Ocean purse seine fishery between 1981 and 2019. Our results showed that the energetic performance of this fishery was characterized by strong interannual variability over the last four decades. This resulted from a combination of variations in tuna abundance but also changes in catchability and fishing strategy. In recent years, the increased targeting of schools associated with fish aggregating devices in response to market incentives combined with the IOTC management measure implemented to rebuild the stock of yellowfin tuna has strongly modified the productivity and spatio-temporal patterns of purse seine fishing. This had effects on fuel consumption and air pollutant emissions. Over the period 2015 to 2019, the purse seine fishery, including its support vessel component, annually consumed about 160,000 t of fuel and emitted 590,000 t of CO2-eq GHG. Furthermore, our results showed that air pollutant emissions can be significantly reduced when limits in fuel composition are imposed. In 2015, SO2 air pollution exceeded 1500 t, but successive implementation of sulphur limits in the Indian Ocean purse seine fishery in 2016 and 2018 have almost eliminated this pollution. Our findings highlight the need for a routine monitoring of fuel consumption with standardized methods to better assess the determinants of fuel consumption in fisheries and the air pollutants they emit in the atmosphere.

Microplastics, a multi-dimensional environmental stressor group, capable of transboundary migration, are a threat to the global ecosystem. Transboundary migration of microplastics across all environmental matrices is known to originate from a multitude of sources and acts in conjugation with each other. This inter-dependence of sources calls for a detailed scientific analysis of all the sources that are in play. Waste management facilities have already been established as a significant contributor of microplastics to the aquatic and terrestrial environment. A systematic overview of the scientific literature reveals that the existing body of scientific knowledge is mainly focused on wastewater treatment facilities as a source/pathway of microplastics in the environment. Recently the focus shifted towards solid waste management facilities through landfills. Poor plastic waste management practices made discarded plastics the most dominant component of solid wastes. This review elucidates the occurrence and distribution of microplastics, characteristics of microplastics, including size, shapes, colors, and polymer types, in leachate and refuse of landfills. Furthermore, we discussed the transport mechanisms and pathways used by microplastic present in landfills to migrate to subsurface or groundwater and adjacent aquatic bodies. Last, based on the findings, we summarized the gaps in existing studies and suggested future perspectives to be focused on the future. The abundance of microplastics is attributed to the volume of plastic waste in landfills, management of leachate originating from landfills, application of leachate, and age of landfills. Microplastics abundance and characteristics vary in leachate and refuse. Smaller microplastics are predominant in leachate while larger microplastics are predominant in refuse. Landfills are capable of generating secondary microplastics from fragmentation and degradation. Further studies on microplastics in landfills are necessary to tackle this ever-growing menace.

The presence of fluoride in the groundwater in the Thirukkazhukundram Block in south India is now becoming an increasingly alarming issue. With the semi-arid climatic conditions, charnockite and gneiss rocks form the basement, contributing to the geology of the study area. The pre-monsoon (August 2016) and post-monsoon (February 2017) fluoride concentrations have an average output of 1.3 mg.L-1 and 0.72 mg.L-1 respectively. As of date, only in Neikuppi, the fluoride contamination is found to be 2 mg.L-1 in pre-monsoon which is beyond the accepted limit as per the WHO standards. Other 29 locations taken up for study have fluoride value fluctuation from 1 mg.L-1 to 2 mg.L-1 in the pre-monsoon and from 0 to 1.5 mg.L-1 in the post-monsoon. The main factor responsible for this fluoride contamination lies in the study area’s hydro-geological condition which must be attended to immediately to prevent a public health problem in the future.

A large part of the total energy consumption in buildings in the Kingdom of Saudi Arabia (K.S.A.), is devoted to air cooling. This leads to high electricity costs for residents and a high amount of equivalent CO2 emissions. The work presented in this paper aims at evaluating and applying shallow geothermal energy for cooling and heating to reduce cost and environmental issues in the Kingdom. The system is based on the earth-air heat exchanger (EAHE) equipped with an air circulation fan. In this study, six cities have been selected; Madinah city, where our university is located, and five other cities representing five different climatic zones. A new parameter called “geothermal percentage” is proposed to calculate the ratio of geothermal energy to the cooling/heating total load. It has been shown that the proposed system covers part of the cooling load and the total heating needs for almost all the country’s territory. However, both heating and cooling needs can be fulfilled by the EAHE for few cities such as Guriiat and Khamis, characterized by a moderate climate.

In the present study, the three main process parameters in the Fenton process for the removal of pharmaceutical compound Mefenamic acid from an aqueous solution were optimized using response surface methodology (RSM). Central composite design (CCD) was used for process optimization. The primary and secondary interaction effects of the selected parameters such as H2O2, Fe2+ and pH on the removal of mefenamic acid were examined. A mathematical model for the removal process based on the selected variables was developed. The interaction effect between the chosen parameters shows that the removal of mefenamic acid was enhanced in the acidic pH range at a high concentration of H2O2 and in a medium concentration level of the catalyst Fe2+. The removal efficiency of 81.24% was obtained for mefenamic acid at the optimized condition of variables such as 9.36 mM H2O2, 0.058 mM Fe2+and at a pH value of 2.1.

A large quantity of trace metals has been continuously polluting the environment as a result of increasing urbanization and industrial processes. In 2016-2017, the metal (Cd, Cu, Cr, Ni, Pb, and Zn) levels were determined in fecal pellets of Blue Rock Pigeon (Columba livia) at Bais Godam (industrial location) in Jaipur and Chittora (rural location) in Rajasthan, India. Fecal pellets in industrial regions which are under higher anthropogenic influence exhibited higher metal concentrations when compared with the fecal pellets of the same species in rural area which have minimal anthropogenic input, with statistically significant industrial-rural differences in the metal concentrations except for Ni. Results obtained in this study, as well as the comparison with literature data, indicated that concentrations of Cr and Cu were high in fecal pellets of Blue Rock Pigeon in the industrial region of the present study. Furthermore, many significant correlations were also observed between metal levels in the industrial region which could be attributed to a similar source. Moreover, contamination levels of pigeon excrement serve as one of the most compelling indicators in terrestrial systems for the monitoring of metal pollution levels.

Low-density plastic bags waste disposal is a big issue in the current scenario which gives rise to grave threats to human beings and environmental health also. Amid the various approaches applied for dealing with the problem, photocatalytic biodegradation in visible light irradiation is an advanced prospect that has received attention nowadays. The present review paper is to provide an outline of the current progress on the synthesis of titania (TiO2) thin-film photocatalysts for solid waste removal. The Photocatalysis method contains the photoinduced redox reactions in the photocatalyst which facilitates the degrading of almost organic compounds like polyethylene into carbon dioxide (CO2), water, and other substance. One of the most excellent photocatalysts which has grabbed attention in an application is titania because of its high photocatalytic activity and chemical stability. The synthesis of the photocatalyst as a thin film is a result of the unfeasible application of conventional powder photocatalyst which may cause a certain environmental hazard. The photocatalyst-coated thin film along with some environmental applications have also been reviewed. Likewise, various approaches for modifying thin-film property, film deposition techniques, and deposition on various substrates are used for the enhanced photocatalytic activity of the TiO2 thin film.