98.7% and 99.8%, and 92% and 90%, respectively, while PO 4 -P removal was about 45% in both columns. Unlike other parameters, NO 3 -N was increasing, which signifies that denitrification did not take place in the filter columns. Based on the results, the filter column of 50 cm is economically preferable due to the insignificant difference when compared with the 100-cm filter column. The bacteria removal was slightly higher in 100 cm depth (99.88%) than in 50 cm depth (99.68%).

Background Solid waste dump sites have proven to have potentially high risk to human health as it serves as a source of air, soil and underground water pollution. Aim This study aimed to assess and compare the knowledge, respiratory disorders and skin disorders between residents living close to and far from landfill sites in Lagos State, Nigeria. Setting Igando (a community within 5 km close to) and Badagry (a community beyond 5 km from) Solous Landfill sites in Lagos state, Nigeria. Methods A comparative cross-sectional study amongst 103 respondents recruited from each of the two study sites by multistage sampling method was carried out. Data were collected using pretested, structured, interviewer-administered questionnaire, and analysed using Microsoft Excel 2007, EPI Info 7 and WinPepi statistical software packages. Student t -test, Fisher’s exact and Chi-square tests were carried out. The p ≤ 0.05 was considered statistically significant. Results The mean age of Igando and Badagry respondents was 34.18 ± 10.21 years and 32.62 ± 9.84 years, respectively. The two communities differed significantly ( p < 0.0001) with respect to distance of workplace from landfill site and duration of stay in the residential location. The mean knowledge score of respondents on respiratory and skin disorders associated with solid waste dump site close to landfill sites (82.53 ± 20.60) was statistically significantly higher than those of respondents far from landfill sites (71.84 ± 20.57) ( p = 0.0003). Respiratory and skin disorders experiences of respondents close to landfill sites were statistically significantly ( p < 0.0001) higher than those of residents far from landfill sites with respect to wheezing, frequent sneezing, unpleasant odour, fever and skin rashes. Conclusion Respiratory and skin disorders experienced by respondents close to landfill sites are higher than those of residents far from landfill sites. Landfill sites should not be located close to human settlements.

The environment is a treasure that needs to be protected from point and diffuse sources of pollution. Most wastewater treatment plants cannot attain 100% efficiencies and this call for tertiary treatment process before discharging final treated wastewater into the environment. The study focused on harnessing the locally available materials, sand and granulated Palm Kernel Shell (gPKS) as filters for treatment of wastewater from constructed wetland using intermittent filtration system in the laboratory. The filter depth and hydraulic loading rate was 650 mm and 0.135 L min -1 , respectively. Applied wastewater was effluent from the Constructed Wetland (CW) of wastewater treatment plant University of Lagos. The filtration system was dosed intermittently 6 hourly for 12 weeks. Experimental results showed that pH of the effluent from gPKS filter medium was slightly reduced to the influent due to acidic nature of the gPKS while effluent from sand filter slightly increased. The five day biochemical oxygen demand (BOD5) removal efficiency for the gPKS and sand filters were 59.2 and 69.08% respectively, while the corresponding average Dissolve Oxygen (DO) were 2.9 ± 0.6 mg L -1 and 3.4 ± 0.345. The percentage removal of E. coli in sand and gPKS filters are 69.34% and 87.49% respectively.