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This study assessed the levels of air pollutants emitted outdoor of farm settlements (FS), the seasonal and temporal variations, and the relationship among the parameters monitored. Seven FS within Ogun State were investigated, with 211 sampling points established across the FS. The concentrations of VOCs, SO2, NO2, CO, O3, NH3, CO2, TSP, PM2.5 and PM10 were monitored in replicates using active potable samplers while bacteria and fungi were isolated using settle plate technique. Descriptive (means and standard deviation) and inferential statistical tools (Pearson correlation) were used to analyse the data. The mean ranges of VOCs, CO and CO2 (ppm); 20.8±10.53 – 48.67±19.05, 17.95±6.65 – 21.5±3.93, 3562.15±1200.85  –  4266±1176.85, and for bacteria and fungi (cfu/m3); 548.98±1.18 – 2255.01±1.27 and 525.68±1.15 – 1282.38±1.27 respectively were above the threshold limits. There were significant seasonal, spatial and temporal differences among observed means of VOCs, CO2 O3, TSP, PM2.5, and fungi. The bacteria and fungi count increased as TSP, PM2.5 and PM10 increased. The study established that levels of air pollutants are dependent on the type of farming practice.

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This study assessed solid healthcare (SHC) waste management practices and levels of heavy metals in soils within four public healthcare facilities in Abeokuta, Nigeria. Walkthrough observation and one-on-one interviews were used to elicit information on waste management practices. Topsoils of waste storage areas were collected and analyzed for heavy metals using Atomic Absorption Spectrometry. SHC general waste is often burnt and buried at the general hospitals while licensed private operators collect it at the Clinics and Specialist hospitals. The Specialist Hospitals generate the highest weight of all the waste categories and in the order; general > infectious > sharps > pathological > pharmaceutical, with the clinic having the highest rate of waste generated/patient (0.8kg/day). Heavy metal concentration (mg/kg) ranges are 5321.46 – 9356.49 (Fe), 96.72 – 314.49 (Zn) and 8.58 – 20.77 (Cr), with an indication of potential non-carcinogenic risks for all exposure routes for both adults and children. Mixed storage of all waste types is still being practised in some healthcare facilities, which portends the risk of infection transmission and environmental pollution. Hence, there is a need to improve the segregation and special handling of SHCW to avoid environmental contamination and negative health-related impacts.

Groundwater forms a very important part of the water supply chain and its quality can be affected by improperly constructed septic tanks used by homeowners in peri-urban locations such as Abeokuta in recent times. Sixty groundwater samples collected from hand-dug wells ≤15m from septic tanks were analysed for physicochemical and bacteriological parameters using standard procedures. Results were integrated with multivariate and hydrogeochemical analyses to assess the effect improperly built septic tanks have on groundwater quality around the Federal University of Agriculture, Abeokuta. The range of values for the measured parameters include: pH (6.26 – 8.66), EC (83 – 1035 μS cm-1), TDS (42 – 621 mg L-1), Mg2+ (2 – 60 mg L-1), NO3- (5.09 – 17 mg L-1), Fe (-.04 – 5.32 mg L-1), BOD (0.1 – 13.2) and E. Coli (ND – 41×10 cfu mL-1). The abundance of major ions are in the order Ca2+˃Mg2+˃K+˃ Na+ and Cl- ˃SO42- >HCO3- >NO3- ˃PO42-. The piper trilinear plot shows that the dominant hydrochemical facies in the study area is the Ca2+–Cl- type. A correlation analysis and a principal component analysis both reflect intrusions from biological wastes such as surrounding septic tanks or municipal waste disposals as well as dissolutions from basal rocks. The possibility of infiltration from sewage into groundwater is confirmed by the number of samples with high BOD, NO3-, and E. coli concentrations. Contamination of groundwater with sewage exposes the populace to acute excreta-related illness. This therefore calls for stringent monitoring and management measures to be put in place by relevant regulatory authorities to safeguard the human health and environment within the study area.