Oriental Journal of Chemistry is a peer reviewed quarterly research journal of pure and applied chemistry. It publishes standard research papers in almost all thrust areas of current chemistry of academic and commercial importance. It provides a platform for rapid publication of quality research papers, reviews and chemistry letters. Oriental Journal of Chemistry is abstracted and indexed in almost all reputed National and International agencies.

A simple spectrophotometric method for the determination of low levels of the orthophosphate (PO43-) in environmental water systems is reported. The method is based the formation of the phosphomolybdate from the condensation of molybdate and orthophosphate in aqueous acid medium followed by reduction with sodium thiosulphate to form phosphomolybdenum blue. The system obeys Beer's law at 880 nm (lambda(max)) in the 0.005-0.06 mg P mL(-1) phosphate concentration range. Molarabsorptivity, Sandell's sensitivity and correlation coefficient values for the determination were 57526 Lmol(-1) cm(-1), 0.2835 mu g cm(-2) and 0.9948 respectively. The limit of detection was 2213 x 10(-8 ) mg P mL(-1). The results of PO43-. determination in water samples obtained using the spectrophotometric method developed in this study, compare favourably with those generated using the Murphy and Riley method which is commonly used for this analysis. Therefore, the study ably demonstrates the suitability of the present spectrophotometric method for analysis of the orthophosphate in environmental water samples.

By the time of this study, Kiteezi landfill was Uganda’s largest waste disposal site and received substantial volumes of municipal solid waste. In the present study, water (n = 36), leachates (n = 36), superficial sediments (n = 30), and Colocasia esculenta corms (n = 6) were sampled from Kiteezi landfill in the dry and wet seasons of 2022 before its tragic collapse in 2024. The physicochemical parameters (pH, electrical conductivity, temperature, and oxidation–reduction potential) and concentration of potentially toxic elements (As, Cu, Cr, Pb, and Zn) were analyzed using standard methods and inductively coupled plasma-optical emission spectrometry, respectively. Significant seasonal variations (p < 0.05) were observed for all the physicochemical parameters of water and leachates except temperature. Further, significantly higher concentrations (p < 0.05) of potentially toxic elements (PTXEs) were quantified in environmental matrices sampled during the dry season than the wet season. Arsenic and Pb concentrations in water surpassed their WHO permissible limit of 0.01 mg/L. The concentrations of PTXEs were higher in downstream samples (p < 0.05), indicating that landfill activities led to their enrichment in matrices near the facility. Ecological and pollution risk indices indicated that there is severe enrichment of Cu and Zn in the sediments, with dry season downstream samples having contamination factors and geoaccumulation indices of 539.3 and 74.7 and 8.5 and 5.6, respectively. Although ingestion of water may not cause probable health risks, consumption of Colocasia esculenta corms could lead to non-carcinogenic and cancer health risks in both children and adults (hazard indices = 0.085–189.0 and total cancer risk values of 7.33 × 10⁻⁶–4.87 × 10⁻³). These results emphasize the need that any new replacement for Kiteezi landfill should be properly planned and managed to mitigate potential environmental pollution with xenobiotics.

In equatorial Africa, rapid urbanization has increased city populations and particulate matter emissions. Street dust is a visual indicator that can be used to track urban pollution. In the present study, the total concentration and speciation of 10 potentially toxic elements (PTEs; As, Cd, Cu, Cr, Ni, Mn, Fe, Pb, Co, and Zn) in dust (n = 36) sampled from three streets of Mbarara City, Uganda, were determined using Energy Dispersive X-ray Fluorescence and Inductively Coupled Plasma-Optical Emission Spectrometry. The concentration of PTEs (0.27–36,401.50 mg/kg) geostatistically indicated moderate to extremely high enrichment of Cd, Cu, and Co in street dust. According to principal component and hierarchical cluster analyses, As, Pb, Cu, Zn, and Cd originated mainly from anthropogenic inputs, Fe and Mn came from geogenic sources, while Cr, Ni, and Co were from both natural and anthropogenic contributions. The mobility of the PTEs followed a general trend, Zn > Co > Cd > Ni > Cr, with Zn and Co being more environmentally mobile. Human health risk assessments indicated that discernible non-carcinogenic health risks may result from ingestion of dust by both children and adults. Children could also experience cancer health effects through the same exposure pathway.