Deterioration in soil–water environment severely contributed by heavy metal bioavailability and mobility on soil surface and sub-surface due to irrational increase in wastewater discharge and agrochemical activities. Therefore, the feasibility of adsorption characteristics of the soil is paramount in curbing the problem of micropollutant contamination in the farming vicinity. Soil from a farming site in a populated area in Enugu, Nigeria was collected and tested to measure the lead and cadmium contents using atomic absorption spectrophotometer (AAS). The adsorption potency of the ultisol soil was estimated for identifiable physicochemical properties by standard technique. The mean activity concentration of Pb2+ and Cd2+ was 15.68 mg/kg and 3.01 mg/kg. The pH, temperature, metal concentration and contact time adsorptive effect on the Pb2+ and Cd2+ uptake was evaluated by batch adsorption technique. The Langmuir, Freundlich and Temkin models were fitted into equilibrium adsorption data and the calculated results depict a better and satisfactory correlation for Langmuir with higher linear regression coefficients (Pb2+, 0.935 and Cd2+, 0.971). On the basis of sorption capacity mechanism of the soil, pseudo-second-order model best described the kinetics of both metal ions retention process. The results of the present study indicated that the soil being a low cost-effective adsorbent can be utilized to minimize the environmental risk impact of these metal ions.

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Industrial effluent discharged into surface water is an environmental concern, as it affects the esthetics, water quality as well as microbial and aquatic flora. Brewery effluents were analyzed for physicochemical parameters (pH, temperature, conductivity, turbidity, total dissolved solids (TDS), dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), nitrate, and sulfate, chloride) and heavy metals (As, Cd, Co, Cr, Fe, Mn, Ni, Pb, and Zn). Atomic absorption spectrophotometer was used to characterize heavy metals using standard analytical methods and compared with WHO standards. The result showed that pH (6.2–6.98), conductivity (137–273 μS/cm), chloride (31–53 mg/l), nitrate (7.53–10.72 mg/l), BOD, and DO were within the WHO limit. However, turbidity, sulfate, and phosphate were above the WHO limit. Heavy metal concentrations Cr, Ni, Pb, Mn, As, and Cd were higher than the WHO limit and vice versa for Fe, Zn, and Co. Ecological risk assessment revealed that effluent samples pose low to moderate ecological risk, for As, Pb, and Ni. Therefore, there is a need for proper treatment and continual monitoring before discharge into the environment.