Polycyclic aromatic hydrocarbons, PAHs are carcinogenic, mutagenic and persistent organic compounds commonly generated from incomplete combustion of organic matters. Beans, Phaseolus vulgaris and maize, Zea mays form part of staple foods commonly consumed and are highly rich in protein and carbohydrate respectively. This study compared the concentration levels of the sixteen priority PAHs in different types of beans (Potasikum, white iron, brown iron, Gausau and Nija red) and maize (white, yellow and pop corn) obtained from various markets in south east Nigeria. The purchased beans and maize samples were picked, ground and extraction was by sonication with a solvent mixture of dichloromethane and hexane in the ratio of 3:1. The determination of PAHs was by gas chromatography coupled with flame ionization detector, GC-FID. The result showed that the PAHs concentration levels (× 10 -2 µg/kg) of lower molecular weight PAHs, LMW detected in the analyzed beans samples ranged from 8.842±4.743 to 12.590±8.068 in white iron beans and brown iron beans respectively with percentages of 41.09% and 44.90% and 5.998±4.725 to 9.385±11.339 in pop and white corn respectively at 25.58% and 34.46%. While the high molecular weight, HMW PAHs concentration levels (× 10 -2 µg/kg) varied from 12.673±5.554 in white iron beans to 16.998±3.129 in Nija red beans at 58.88% and 63.95% and from 17.84±11.768 in pop maize to 18.153±10.421 in yellow maize at 74.83% and 67.43% respectively. The probable carcinogenic PAH8 concentrations detected varied from (8.875±2.725 to 11.796±3.018) × 10 -2 µg/kg in white iron beans and brown iron beans respectively and from (10.82±6.183 to 13.573±8.789) × 10 -2 µg/kg in pop and yellow maize respectively.. Diagnostic ratio calculated showed fuel combustion to be the main source of emission. The sixteen priority PAHs were detected in all the analyzed samples at a very low concentration levels, lower than the permissible limit of 1.0 µg/kg established by EFSA for cereals and cereal based products. Hence these (PAHs) can at a long time accumulation in the body be very harmful. There is need to establish a permissible limit of PAHs in beans and other legume grains by either European Food Safety Authority, EFSA or other regulatory bodies.

Pharmaceutical effluents are wastes generated by pharmaceutical industries during the process of drug production.Pharmaceutical industry effluent is hazardous in nature due to its components such as toxic metals and active pharmaceutical ingredients and therefore should be treated before it is discharged into any water body or on to soil. But studies have shown that in most developing countries like Nigeria, industries dispose their effluents without treatment. The pharmaceutical effluents can be treated using inorganic or natural coagulants. This paper reviewed some studies on the treatment of pharmaceutical effluents using natural coagulants which are low-cost, under-utilized, economic friendly and readily available. The coagulants reviewed include Moringa oleifera, Citrullus lanatus (Seed of watermelon), Treculia africana (African bread fruit), Phoenix dactylifera (Date), Zea mays (Corn or maize), Banana peels, Sesamum indicum (Beniseed). The studies were critically reviewed with respect to the type of natural coagulant used, method of application to the effluents and result obtained. The results from the studies reviewed revealed that the treatment efficiency was maximally achieved in each case when the natural coagulants were used in combined form (either with another natural coagulant or inorganic coagulant) in appropriate ratios. Treatment efficieny of pharmaceutical effluents is obtained by using combined natural coagulant.

Biodiesel has been referred to as a perfect substitute for diesel fuel due to its numerous promising properties. They are renewable, clean, increases energy security, improves the environment and air quality and also provides some good safety benefits. This study is focused on the investigation of the use of natural heterogeneous catalysts for production of biodiesel from jansa seed oil, as well as the implementation of artificial neural network (ANN) for the prediction of biofuel yield and process parameters. The biodiesel was produced through transesterification reaction by reacting jansa seed oil (FFA) with methanol (alcohol) to yield methyl ester. Waste periwinkle shell was prepared in 3 different forms; raw, calcined and acidified. The percentage yield of the methyl ester obtained were calculated and tabulated. The process parameters considered were methanol-oil mole ratio, catalyst concentration, agitation speed, reaction temperature and reaction time. The results of this research work revealed that the calcined periwinkle shell catalyst produced higher yield of biodiesel, compared to the yield obtained from the raw and acidified catalyzed process. The properties of the fatty acid methyl esters were within the standard range. The experimental and predicted yield were marginally the same. Hence, the model accurately predicted the yield with acceptable coefficient of determination and low mean squared error (MSE). The results demonstrate the flexibility of ANN model and the improvement of the model in terms of performance prediction when solving problems with stochastic dataset, especially the transesterification of biodiesel.