Potentially Toxic Elements in Urban Soils from Public-Access Areas in the Rapidly Growing Megacity of Lagos, Nigeria

Abstract

Rapid urbanization can lead to significant environmental contamination with potentially toxic elements (PTEs). This is of concern because PTEs are accumulative, persistent, and can have detrimental effects on human health. Urban soil samples were obtained from parks, ornamental gardens, roadsides, railway terminals and locations close to industrial estates and dumpsites within the Lagos metropolis. Chromium, Cu, Fe, Mn, Ni, Pb and Zn concentrations were determined using inductively coupled plasma mass spectrometry following sample digestion with aqua regia and application of the BCR sequential extraction procedure. A wide range of analyte concentrations was found—Cr, 19–1830 mg/kg; Cu, 8–11,700 mg/kg; Fe, 7460–166,000 mg/kg; Mn, 135–6100 mg/kg; Ni, 4–1050 mg/kg; Pb, 10–4340 mg/kg; and Zn, 61–5620 mg/kg—with high levels in areas close to industrial plants and dumpsites. The proportions of analytes released in the first three steps of the sequential extraction were Fe (16%) < Cr (30%) < Ni (46%) < Mn (63%) < Cu (78%) < Zn (80%) < Pb (84%), indicating that there is considerable scope for PTE (re)mobilization. Human health risk assessment indicated non-carcinogenic risk for children and carcinogenic risk for both children and adults. Further monitoring of PTE in the Lagos urban environment is therefore recommended.

Urban environmental monitoring and health risk assessment introducing a fuzzy intelligent computing model

“…The study employed historical monitoring data for the purpose of training and optimization, ensuring the precise modeling of the intricate relationship between the tangible environment and health parameters ( 15 , 16 ). Through the consideration of fuzzy relationships among various environmental factors, the study achieved a comprehensive evaluation of health risks ( 17–20 ).…”

Spatial Distribution and Health Risk Evaluation of some Potentially Hazardous Elements in Akure Urban Topsoil, Nigeria

“…The soil samples were air-dried in a dust free open laboratory, disaggregated and sieved using a 2 mm sieve (BS) (Brigden et al, 2008). Physicochemical parameters were carried out using standard procedures (Wilke, 2005)) and the PHEs (Cd, Mn, Ni and Pb) extracted with aqua regia, the extracts analyzed using Atomic Absorption Spectrophotometer (Buck Scienti c model 210) (Famuyiwa et al, 2022). The descriptive statistical analysis (minimum, maximum and mean) was conducted using SPSS 20.0 software.…”

How do individual-level factors influence the adoption of low-carbon technology? Proposing and validating the bioeconomy technology acceptance model in the context of Africa

“…The sample size was estimated to be 400, based on estimates of the population in Lagos (Famuyiwa et al, 2022). However, to overcome the risks of non-responses or poorly answered questionnaires, the number obtained was divided by the expected response of 80%, which is considered acceptable (see Fincham, 2008;Ewing et al, 2018) to get 500 as the study population.…”