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Soil plays crucial and strategic life-supporting roles as man and many other living organisms depend directly or indirectly on if for food and shelter. In spite of this fact, the soil is constantly subjected to various forms of abuse, including heavy metals pollution. The ecological destructive effect, high cost, and intensive labour requirement associated with ex situ physico-chemical remediation methods make the search for in situ remediation techniques inevitable. This paper gives an update on the remediation techniques that can be carried out in situ. Included in the review are more recent biological remediation methods, like vermiremediation, which are especially eco-friendly, cost effective, and sustainable.

Polychlorinated biphenyls (PCBs) are a class of non-polar toxic chemical compounds consisting of 209 congeners of which only about 130 have been identified in commercial products (Berg et al., 2017). PCBs are used in industrial applications such as hydraulic fluids, lubricants, inks, plasticizers, agrochemicals, etc. from which they leak into soil, surface and underground water (Cappelletti et al., 2015). Discharge of industrial waste into water bodies, and incineration are predominant sources of PCBs in Nigeria (Wang, 2002; Okoh, 2015). Waste management in Epe, Nigeria include land filling, dumping site, and open incineration. These methods are liable to contaminate underground and surface water bodies, thereby gaining access to the aquatic food chain where they are biomagnified up the ARTICLE INFO

Introduction.There have been no studies, monitoring programs, or data about phthalate levels made available to the public on the safety of residential drinking water in Lagos, Nigeria.Objectives.The present study aimed to assess the concentrations of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), and zinc (Zn), lead (Pb), chromium (Cr), and cadmium (Cd) in drinking water drawn from taps in three residential areas of the state.Methods.High performance liquid chromatography and atomic absorption spectroscopy were used to determine the concentrations of phthalates and metals, respectively.Results.All of the water samples collected throughout the sampling period contained DMP, while DEP and DBP were present in only some of the samples. The highest mean DMP, DEP, and DBP concentrations of 1.15±0.28 mg/l, 0.09±0.16 mg/l, and 0.28±0.33 mg/l, respectively, were found in water samples collected from Lagos Street (Ebute-metta East). In addition, the trace/toxic metal concentrations in the water samples were found to be low for Cr, but high for Cd, Pb, and Zn, especially when compared with World Health Organization (WHO) limit values for drinking water. Lead recorded the highest mean concentration of 0.087±0.021 mg/l in the water samples obtained from Apapa Road (Ebute-Metta West). In the same vein, the highest significant (P < 0.01) mean Cr concentration of 0.047±0.012 mg/l was found in the water samples obtained from Apapa Road (Ebute-Metta West).Conclusions.In view of the high concentrations of phthalates and metals in the water sampled in this study, and the potential adverse health effects of these contaminants, especially on children and women of child-bearing age, the Lagos State Government of Nigeria and the state water corporation are called upon to immediately institute a monitoring program to identify the sources of contaminants and take appropriate intervention measures.Competing Interests.The authors declare no competing financial interests.

This paper examines air pollution situation and the history of air quality management in Botswana. The current air quality management in Botswana is still largely underpinned by the Atmospheric Pollution Prevention Act of 1971, supplemented by the more recently enacted legislations such as the Environmental Impact Assessment (EIA) Act of 2010 and the Ambient Air Quality - Limits for Common Pollutants of 2012 published by the Botswana Bureau of Standards. Though commendable efforts have been made toward legislating against air and other forms of pollution, these have not yielded expected results in view of the prevailing levels of air pollutants like sulphur dioxide and fine particulate matters in the country’s atmospheric environment. Legislation as a sole measure may not be effective in tackling this challenge. Rather, government should also address some root-causes of the problem by making policies and programmes that will reduce unemployment and increase the earning capacity of citizenry. This will, among other things, effectively check poverty-induced biomass burning in the country. The paper looks at some other challenges of air pollution management and suggestions are made to tackle the identified problems.