Appraisal of Heavy Metal Contents in Commercial Inorganic Fertilizers Blended and Marketed in Nigeria

Abstract Human food chain toxicity has been shown to be influenced by application of inorganic fertilizers. Three samples of commercial inorganic fertilizers marketed in Nigeria were analysed for their heavy metal contents. The fertilizer samples used were N 15 P 15 K 15 (CF1), N 20 P 10 K 10 (CF2) and N 27 P 13 K 13 (CF3). Molybdenum (Mo) levels were the highest and Vanadium (V), Arsenic (As), Mercury (Hg) and Silver (Ag) were not detected by our analytical method. The concentrations of Mo in the CF1 (2, 570.0 mg/kg), CF2 (2,3000.0 mg/kg) and CF3 (1,340.0 mg/kg), were above the maximum acceptable concentration (20mg/kg) while CF1 (0.129 mg/ha/yr) and CF2 (0.115 mg/ha/yr) were above the maximum annual metal addition to soil (0.079 mg/ha/yr), as established by Canadian standard for fertilizers. Only CF1 (5.805 kg/ha) was above long-term cumulative assessment of metal addition to soil (3.57 kg/ha). Other heavy metals detected were Magnesium(Mg), Iron(Fe), Nickel(Ni), Zinc(Zn), Cadmium(Cd), Manganese(Mn), Cupper(Cu), Cobalt(Co), Lead(Pb), Chromium(Cr) and Boron(B). Cd and Pb mean concentrations of the fertilizer samples examined ranged from 2.84 to 11.32 mg/kg and 7.43 to 9.02 mg/kg respectively. Cd followed significantly (p<0.05) with phosphate percentage by weight of the inorganic fertilizers. Though the concentrations of these non-nutrient/toxic metals were below the recommended levels, it is important to encourage manufacturers to indicate their concentrations on the fertilizer labels in view of their health implications

Dual Solution Synthesis and Characterization of Sns:Zns Alloyed Thin Films and Possible Applications in Solar Systems and Others

Communication in Physical Sciences, 2023, 9(2):172-198 Authors: Elizabeth C. Nwaokorongwu, Daniel A. Asiegbu, Lebe Nnanna, Ugochukwu Joseph, Akpu Nwamaka and K.U.P. Okpechi Received: 12 March 2023/Accepted 18 May 2023/ Energy is required for the creation of wealth and sustainability of development. The importance of energy in economic development has been recognized historically but the equitable distribution of energy amongst the masses has generated great concern in recent times.  This study was conducted to investigate the influence of varying annealing temperatures on the synthesis and characterization of SnS:ZnS alloyed thin films for solar applications. SnS:ZnS alloyed thin films were successfully deposited on glass substrates using two solutions-based methods: electroless and SILAR. The deposited alloyed sulphides were annealed between (373-423) K using a master chef annealing machine. The crystallographic studies were done using X-ray diffractometer and scanning electron microscope which indicates that the samples are polycrystalline and have cubic crystal systems. Rutherford Back Scattering analysis confirmed the percentage of the elements of tin, zinc and sulphur in the alloyed sulphide thin films. The results of the findings revealed that alloyed materials were deposited. The deposited materials were uniform and adherent to the substrates. The structural properties show that SnS:ZnS are polycrystalline. The microstructure shows the optical micrograph of the deposited samples. The properties exhibited make the films good material for protective coating, window coating, galvanization of metal and non-metal surfaces to prevent corrosion, etc. These properties also enhanced the material suitability for photovoltaic (PV) in solar energy conversion, sensors for the detection of poisonous substances most especially in the Oil-producing areas, light emitting diode (LED) and flat panel displays for optoelectronic applications