Bioaccumulation of heavy metals in freshwater Clarias anguillaris and Parachanna africana from Lake Geriyo in Yola, Nigeria

This study was carried out to determine the bioaccumulation of heavy metals in Clarias anguillaris and Parachanna africana from Lake Geriyo Yola, Nigeria using energy dispersive X-ray fluorescence (EDXRF) spectrophotometer. The results in (mg/kg, dry weight) showed different levels of Cr, Cu, Mn, Fe, Ni, Zn, and Pb in the two fish species. The order of heavy metals accumulated by C. anguillaris and P. africana are Cr>Fe>Zn > Mn>Cu>Ni>Pb and Ni>Fe>Zn>Cu respectively. The levels of Cr, Mn and Ni in C. anguillaris and in Ni in P. africana were higher than WHO and FEPA recommended maximum permissible limits (MPL) in fish, while the levels of Zn, Cu and Pb were below the standards. The results suggest that Lake Geriyo has high pollution loads of these heavy metals in fishes and could pose a health hazards to man. Consequently, close monitoring of heavy metal loads in Lake Geriyo is recommended with a view to minimizing the risks to health of the population that depend on the lake for their water and fish supply

Perceived Impact of Empowerment through Agricultural Entrepreneurship among Nigerian Graduate Youth

Youth unemployment is a concern in the developing world due to lack of industries to absorb youth. This gemeric qualitative study involved exploring Nigerian graduates of entrepreneurship training in agriculture and their empowerment experiences involving pursuing a related career. The study centered on elimination of poverty from an interdisciplinary perspective. The critical social theory and resilience theory were used as conceptual frameworks. The study included 10 trainee interviews via convenience sampling who worked on an agricultural farm and involved obtaining open-ended data concerning their experiences. Data analysis in the study involved a manual process and Microsoft word was used for its imputation. Interviews used in the study generated five themes involving feelings of participants : adopting agricultural practice as a business necessity for the non-availability of white-collar jobs, involvement in farm training and farming does not mean cultivating or farming vast acres of land techniques and practices, stakeholders’ experiences could provide tangible outcomes, human and social service practices are not used but desirable, and the success of youth involvement in agribusiness was not only about income generation. This study gives human and social services practitioners in Nigeria information to comprehend their activities to provide advocacy counseling, social action, and social justice. The social change inference offers scholars with a greater understanding of human services administrators and educators in the provision of skill identification and competency-building designs in Nigeria to enact social change involving university graduates with a ripple effect on community development

Evaluations off heavy metals in fish from Lake Geriyo Yola, Nigeria using x-ray fluorescence technique

The evaluation of Cr. Cu, Mn, Fe, Ni, Zn,As and Pb concentrations in Clarias gariepinus and Oreochromis niloticus from Lake Geriyo Yola,Adamawa, Nigeria using X - ray fluorescence (XRF) technique is discussed. The analytical samples are irradiated with high energy electrons of 109Cd to produce fluorescent X-rays was produced which passes to the Silicon-lithium detector through Mo target as a source of monochromatic X-rays. The spectrum of energy generated on the detector was processed by a Multi- Channel Analyzer to obtain analytical data. The intensity of the fluorescent X-rays on the detector is proportional to the concentration of the individual element of interest in the sample. This method can identify up to 30 or more elements at the same time. The results showed varying levels of heavy metals in the fishes. The concentrations of Cr, Mn, Cu, and Ni in the fishes were much higher than WHO and PEPA maximum permissible limits, while the concentrations of Zn and Pb were lower than the standards. The results suggest that the lake is polluted with Cr, Mn, Cu and Ni and the consumption of fishes of the lake is life threatening to man

Modulating the Hydration Behaviour of Calcium Chloride by Lactam Complexation

Complexation of calcium chloride with bis(lactam) ligand L1 allows the formation of both an unstable anhydrous complex, an aqua complex {[Ca2(μ-L1)2(H2O)9]Cl4]}n (1) and a related hydrate incorporating additional lattice water of crystallization {[Ca(μ-L1)(H2O)5]Cl2·H2O}n (2). Related mono(lactam) L2 does not form aqua complexes but the anhydrous complex {[CaCl2(μ-L2)2]}n (3), is highly deliquescent. An unusual ethanol solvate is also reported {[CaCl2(L2)(EtOH)]}n (4)

N-alkyl pyrrolidone ether podands as versatile alkali metal ion chelants

This work explores the coordination chemistry of a bis(pyrrolidone) ether ligand. Pyrrolidones are commercially important functional groups because of the high polarity and hence high hydrophilicity and surface affinity. An array of alkali metal ion complexes of a podand bearing two pendant pyrrolidone functionalities, namely 1-{2-[2-(2-oxo-pyrrolid-1-yl)-ethoxy]-ethyl}-pyrrolid-2-one (1) are reported. Reaction of this ligand with sodium hexafluorophosphate gives two discrete species of formulae [Na(1)2]PF6 (3) and [Na3(H2O)2(μ-1)2](PF6)3 (4), and a coordination polymer {[Na3(μ3-1)3(μ2-1)](PF6)3}n (5). The same reaction in methanol gives a 1 : 1 complex, namely [Na2(μ-1)2(MeOH)2](PF6)2 (6). Use of tetraphenyl borate as a less coordinating counter ion gives [Na2(1)2(H2O)4](BPh4)2 (7) and [Na2(1)4](BPh4)2 (8). Two potassium complexes have also been isolated, a monomer [K(1)2]PF6 (9) and a cyclic tetramer [K4(μ4-H2O)2(μ-1)4](PF6)4 (10). The structures illustrate the highly polar nature of the amide carbonyl moiety within bis(pyrrolidone) ethers with longer interactions to the ether oxygen atom. The zinc complex is also reported and {[ZnCl2(μ-1)]}n (11) exhibits bonding only to the carbonyl moieties. The ether oxygen atom is not necessary for Na+ complexation as exemplified by the structure of the sodium complex of the analogue 1,3-bis(pyrrolid-2-on-1-yl)- butane (2). Reaction of compound 1 with lithium salts results in isolation of the protonated ligand

Structure and hydration of polyvinylpyrrolidone-hydrogen peroxide

The structure of the commercially important polyvinylpyrrolidone-hydrogen peroxide complex can be understood by reference to the co-crystal structure of a hydrogen peroxide complex and its mixed hydrates of a two-monomer unit model compound, bisVP·2H2O2. The mixed hydrates involve selective water substitution into one of the two independent hydrogen peroxide binding sites

Graz. Burgtor-Hofgasse

Blick durch das Burgtor in Richtung Hofgass

Uptake of Ultrashort Chain, Emerging, and Legacy Per- and Polyfluoroalkyl Substances (PFAS) in Edible Mushrooms (Agaricus spp.) Grown in a Polluted Substrate

Uptake of 19 per- and polyfluoroalkyl substances (PFAS), including C3–C14 perfluoroalkyl carboxylic acids (PFCAs), C4, C6, and C8 perfluoroalkyl sulfonates (PFSAs), and four emerging PFAS, was investigated in two mushroom species (Agaricus bisporus and Agaricus subrufescens) cultivated in a biogas digestate-based substrate. Accumulation of PFAS in mushrooms was low and strongly chain-length dependent. Among the different PFCAs, bioaccumulation factors (log BAFs) decreased from a maximum of −0.3 for perfluoropropanoic acid (PFPrA; C3) to a minimum of −3.1 for perfluoroheptanoate (PFHpA; C7), with only minor changes from PFHpA to perfluorotridecanoate (PFTriDA; C13). For PFSAs, log BAFs decreased from perfluorobutane sulfonate (PFBS; −2.2) to perfluorooctane sulfonate (PFOS; −3.1) while mushroom uptake was not observed for the alternatives 3H-perfluoro-3-[(3-methoxy-propoxy)propanoic acid] (ADONA) and two chlorinated polyfluoro ether sulfonates. To the best of our knowledge, this is the first investigation of the uptake of emerging and ultra-short chain PFAS in mushrooms, and generally the results indicate very low accumulation of PFAS.publishedVersio