Nigerian Journal of Chemical Research

Metal Leaching: Release from Kindergarten Books in Simulated Saliva Conditions

S C Onuchukwu — 2025-05-28

The leaching of metals from consumer products, especially those intended for children, poses significant health risks, particularly during prolonged exposure. This study investigates the release of metals from kindergarten books under conditions mimicking saliva, simulating real-world interactions where children may explore books orally. The experiment, conducted in a controlled lab, exposed books to a saliva-like solution for various time periods. Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) was used to quantify toxic metal concentrations (As, Cd, Cu, Ni, Pb). Results showed concentrations of toxic metals (mg/kg) ranging from 2.85 to 40.7 for As, 1.83 to 38.9 for Cd, 9.78 to 159 for Cu, 2.85 to 11.2 for Ni, and 36.1 to 111 for Pb. Correlation analysis revealed a significant positive correlation between As and Ni. Saline extraction produced no detectable As in some samples, while Cu was found in all. Stomach acid extraction showed varying levels of Pb, As, and Cu, indicating potential health risks. The health index (HI) for most samples exceeded 0.1 for As, Cu, and Pb, with As having the highest HI values. These findings highlight the risks of metal migration from printed materials and the need for safer alternatives in children's educational resources.

13C NMR Study On Structure, Composition and Curing Behavior of Bio-Phenol Formaldehyde Resole Resin

Y B Olayiwola — 2025-05-28

Liquid-state 13C Nuclear Magnetic Resonance (NMR) spectroscopy was employed to characterize BPF resole resins. The 13C NMR analysis revealed that condensation reactions between bark phenolic compounds and formaldehyde occurred during resin synthesis. Notably, the BPF resin exhibited more pronounced methylene ether bridges compared to the conventional PF resin system. The 13C NMR study highlighted significant structural differences in the resins induced by the incorporation of bark-phenolic components. The inclusion of bark-phenolic components favored the formation of para-ortho methylene linkages in the BPF resins, which also enhanced the cure rate of the BPF resin system

Determination of Phthalate Esters in Soft Drinks by Gas Chromatography and Mass Spectrometry

O E Odumade — 2025-05-28

This study investigates the presence of phthalate esters in bottled soft drinks and evaluates the associated health risks and regulatory considerations. Extraction was done using 15 mL of dichloromethane (DCM). A gas chromatograph equipped with a split/splitless injector and an auto-sampler coupled with a triple quadrupole mass spectrometer was employed for the analysis. Analysis of various brands revealed significant concentrations of di(2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate (DBP);DEHP had the highest concentration in Tem (36.17µg/mL) and the lowest in Sup(22.44µg/mL), while DBP ranged from 12.97µg/mL in Mira to 22.87µg/mL in Tem. DEHP also demonstrated the highest mean concentration of 28.20 ± 5.75 µg/mL. Known for its adverse effects on liver and testes. These findings underscore the potential health hazards associated with phthalate exposure, particularly to vulnerable populations. Regulatory comparisons highlight the absence of universally accepted maximum contaminant levels for phthalates in beverages, emphasizing the need for standardized guidelines to safeguard consumer health. Furthermore, discussions encompass the influence of storage conditions on phthalate leaching, with higher temperatures exacerbating contamination levels. Recommendations include consumer education on proper storage practices, industry adoption of phthalate-free packaging, and global harmonization of regulatory frameworks.

Brewery Wastewater Treatment using Biocoagulants from Cassava Leaves

H Mahmud — 2025-05-28

Concerns over the use of traditional metal-based coagulants and flocculants to remove suspended particles from wastewater and drinking water are growing now. Concerning themes these days include the created non-biodegradable sludge's continued impact on human health and further degradation of aquatic habitats. Using the right treatment techniques to lower the pollutant level in receiving waters is essential to achieving coagulation. Using cassava leaf as a bio-coagulant, this study examines the coagulative decrease of turbidity, COD, BOD, and color from brewery wastewater. A Fourier Transform Infrared Spectrophotometer (FTIR) and a scanning electron microscope (SEM) were used to acquire and study these bio-coagulants for their spectrum and morphological properties. The physical-chemical characteristics of the wastewater from the brewery were examined both before and following treatment. The outcome exhibited a natural pH of 7.7 at 300 degrees Celsius. pH (5-8), coagulant dose (0.2–1.0g), temperature (400–700C), settling time (10–70mins), and particle size (0.212, 0.315, 0.5, 1.0, 2.0mm) were the factors evaluated on the coagulation–flocculation process of the brewery wastewater. The factors examined in relation to reduction efficiency revealed that as pH increased, color intensities fell from 75.64% to 70.48%. The Total Suspended Solids (TSS) drop as pH rises, from 81.89% to 79.67%. With an increase in pH, turbidity rises from 38.8% to 41.06%. At 0.3g/L of cassava leaf, the maximum decrease in turbidity was 51.22%, COD was 39.79%, BOD was 100.62%, and color was 4.7%. R2 = 0.95 was obtained by fitting the data using a pseudo first order coagulation kinetics model. At greater R² shows that the model matches the data the best. Using the kinetic parameter (R₂), PFO and PSO have respective values of 0.95 and 1.

Assessment of Phytochemicals, Physicochemical Properties of Oils from Neem (Azadirachta indica) And Watermelon Seeds (Citrullus lanatus) Found in Jos, Plateau State. Nigeria.

J D Dodo — 2025-05-28

Seeds of Neem and Watermelon were collected from two locations in Plateau State. Oils were extracted as Neem Seed Oil (NSO) and Watermelon Seed Oil (WSO) by cold Press method. The oils were analysed for phytochemicals, physicochemical as well as organoleptic properties. NSO was golden brown, had a garlic smell, viscous with a bitter taste, while WSO was golden yellow, fruity smell, light bitter taste. Phytochemicals present were Saponins, Terpenoids, Tannins and Steroids in both oils while phenols, amino acids and carbohydrates were absent in the oils. Alkaloids were present in WSO. The percentage yield (73.5% , 77.5%), moisture content (0.045±0.058%, 0.019±0.132%), density (0.752±0.021 gcm³, 0.795±0.136 gcm³), specific gravity (0.768±0.003, 0.811±0.001), saponification value (28.05±0.03 mg KOH/g, 64.515±0.06 mg KOH/g), peroxide value (52±1.34, 6±0.56), acid value (5.61±0.73, 2.805±0.15), free fatty acid value (2.805±0.181, 1.403±0.266), pH (4.43±0.45, 7.21±0.38) for NSO and WSO respectively. The study showed that these oils may not be suitable for the production of soaps but suitable for the manufacture of skin and hair care products, where it can serve as carrier oils. The presence of flavonoids, terpenoids and tanins in NSO shows its potential use for pesticidal, medicinal purposes. The WSO can be an alternative source of biodiesel.