Self-assembly of ZnO-Biochar/Kaolinite/Chitosan/GO with 1D/2D/3D heterojunctions for enhanced removal of estrogens and triclosan in water.

This Study focuses on the preparation of sustainable and efficient Chitosan catalyst for the removal of three organic pollutants, 17β-Estradiol (E2), 17α-ethynyl estradiol (EE2) and triclosan (TCS) from water. The prepared nanocomposites were characterized by different techniques which confirmed the presence of the key components Chitosan, Carica Papaya seed and Kaolinite. The optical characterization proved the nanocomposite is photoactive with a band gap of 1.

Association Between Urinary Parabens and Sperm Quality in Nigerian Men: A Case-Control Study.

Background: Parabens, which are chemicals used as preservatives in cosmetic and pharmaceutical products, have been reported to be associated with low sperm quality in animal and human models. Despite the high exposure of men to paraben-containing products in Nigeria, there are no known studies that investigate the association of parabens with sperm quality in the country.

Objective: To determine the association of urinary levels of metabolites of parabens with sperm count and quality.

Perovskite Oxides: Syntheses and Perspectives on Their Application for Nitrate Reduction.

Over the decades, the rise in nitrate levels in the ecosystem has posed a serious threat to the continuous existence of humans, fauna, and flora. The deleterious effects of increasing levels of nitrates in the ecosystem have led to adverse health and environmental implications in the form of methemoglobinemia and eutrophication, respectively. Different pathways/routes for the syntheses of perovskites and their oxides were presented in this review.

Association of Urinary Mycotoxins with Sperm Quality: A Case-Control Study in Southern Nigeria.

The objective of this study was to determine the association between mycotoxins and the quality of spermatozoa in Nigeria. We designed a prospective case-control study involving 136 men diagnosed with reduced sperm count and quality in five infertility clinics in southwest Nigeria and 154 normal fertile controls. Sperm analysis was conducted in accordance with the recommendations of the World Health OrganizationWHO, while Liquid Chromatography-Mass Spectrometry was used to assay three metabolites of mycotoxins (zearalenone, ochratoxin A, and deoxyvinelol) in the urine samples of cases and controls.

Occurrence profiling, risk assessment, and correlations of antimicrobials in surface water and groundwater systems in Southwest Nigeria.

The presence of antimicrobials in water has grown into a major global health concern. This study thus focused on the presence, ecological implications, and potential health risks associated with nine antimicrobials: five antibiotics (ampicillin, chloramphenicol, ciprofloxacin, metronidazole, and tetracycline) and four parabens (methylparaben, ethylparaben, propylparaben, and butylparaben) in surface water and groundwater samples collected from three Southwestern States in Nigeria (Osun, Oyo, and Lagos States). These antimicrobials were widely detected across the three States with ciprofloxacin being the most dominant having maximum average concentrations of 189 μg L and 319 μg L in surface water and groundwater respectively.

Distribution and toxicity of dihydroxybenzenes in drinking water sources in Nigeria.

This study provides, for the first time, data on the distribution and toxicity of catechol (CAT) and hydroquinone (HQ) in drinking water sources from Africa. Groundwater (boreholes and hand-dug wells) and surface water in three Southwestern States in Nigeria served as sampling sites. The concentrations of CAT and HQ in groundwater and surface water were determined throughout a period of 12 months, evaluating the effects of seasonal variation (rainy and dry seasons).

Cellulose-based adsorbents for solid phase extraction and recovery of pharmaceutical residues from water.

Cellulose has attracted interest from researchers both in academic and industrial sectors due to its unique structural and physicochemical properties. The ease of surface modification of cellulose by the integration of nanomaterials, magnetic components, metal organic frameworks and polymers has made them a promising adsorbent for solid phase extraction of emerging contaminants, including pharmaceutical residues. This review summarizes, compares, and contrasts different types of cellulose-based adsorbents along with their applications in adsorption, extraction and pre-concentration of pharmaceutical residues in water for subsequent analysis.

Efficient Removal of Tetracycline and Bisphenol A from Water with a New Hybrid Clay/TiO Composite.

New TiO hybrid composites were prepared from kaolin clay, predried and carbonized biomass, and titanium tetraisopropoxide and explored for tetracycline (TET) and bisphenol A (BPA) removal from water. Overall, the removal rate is 84% for TET and 51% for BPA. The maximum adsorption capacities () are 30 and 23 mg/g for TET and BPA, respectively.

Pollution and risk assessment of phenolic compounds in drinking water sources from South-Western Nigeria.

This study reports the occurrence and risk assessment of 2,4-dinitrophenol (2,4-DNP), phenol (PHE), and 2,4,6-trichlorophenol (2,4,6-TCP) in drinking water sources in three south-western States in Nigeria (Osun, Oyo, and Lagos). Groundwater (GW) and surface water (SW) were collected during dry and rainy seasons of a year. The detection frequency of the phenolic compounds followed the trend Phenol > 2,4-DNP > 2,4,6-TCP.

Antibiotic resistomes and their chemical residues in aquatic environments in Africa.

The aquatic environment is a hotspot for the transfer of antibiotic resistance to humans and animals. Several reviews have put together research efforts on the presence and distribution of antibiotic resistant bacteria (ARB), antibiotic resistance genes (ARGs), and antibiotic chemical residue (ACRs) in food, hospital wastewater, and even in other aquatic environments. However, these reports are largely focused on data from developed countries, while data from developing countries and especially those in Africa, are only marginally discussed.

Causes and Risk Factors for Male Infertility: A Scoping Review of Published Studies.

Background: Despite the evidence of declining sperm counts worldwide and the increasing prevalence of male infertility, there has been limited documentation of the potential causes and risk factors for male infertility. With limited methods of primary treatment of male infertility, understanding the causes and risk factors will pinpoint specific lines of prevention.

Objective: We reviewed published studies on causes and risk factors for male infertility and identify gaps in the literature enabling more focused research and innovations.

Green synthesis of ZnO coated hybrid biochar for the synchronous removal of ciprofloxacin and tetracycline in wastewater.

Preparation of biochar from kaolinite and coconut husk (KCB) and further activated with HCl (KCB-A) and KOH (KCB-B) a microwave technique for the remediation of ciprofloxacin (CIP) and tetracycline (TET) from water was carried out. Characterization using scanning electron microscopy, energy dispersive X-ray, Fourier transform infrared spectroscopy and X-ray diffraction showed the successful synthesis of functionalized biochars. Batch adsorption experiments demonstrated the potential of the adsorbents for fast and efficient removal of CIP and TET from solution.

Occurrence and human exposure assessment of parabens in water sources in Osun State, Nigeria.

Parabens are chemicals extensively used in pharmaceuticals, cosmetics, personal hygiene and food products as preservatives. They are classified as emerging contaminants with endocrine-disrupting capability. In this study, the concentrations of Methylparaben (MeP), Ethylparaben (EtP), Propylparaben (PrP) and Butylparaben (BuP) were obtained from groundwater, surface-water and packaged water samples collected from urban and rural areas of Osun State, Nigeria using HPLC-UV equipment.

Toxicity and removal of parabens from water: A critical review.

Parabens are biocides used as preservatives in food, cosmetics and pharmaceuticals. They possess antibacterial and antifungal activity due to their ability to disrupt cell membrane and intracellular proteins, and cause changes in enzymatic activity of microbial cells. Water, one of our most valuable natural resource, has become a huge reservoir for parabens.

Clean technology for synchronous sequestration of charged organic micro-pollutant onto microwave-assisted hybrid clay materials.

The Sustainable Development Goal 6 (SDG #6) of the United Nations (UN) is hinged on the provision, availability, and sustainability of water for the global populace by 2030. In a bid to achieve this goal, the quest to seek for ubiquitous and low-cost adsorbents to treat effluents laden with industrial dyes, such as methylene blue (MB), is on the increase in recent years. Acute exposure of humans to (MB) dye causes cyanosis, necrosis, and jaundice and even leads to death.

Visible-Light-Mediated Photodynamic Water Disinfection @ Bimetallic-Doped Hybrid Clay Nanocomposites.

This study reports a new class of photocatalytic hybrid clay nanocomposites prepared from low-cost sources (kaolinite clay and seeds) doped with Zn and Cu salts via a solvothermal process. X-ray diffraction analysis suggests that Cu-doping and Cu/Zn-doping introduce new phases into the crystalline structure of Kaolinite clay, which is linked to the reduced band gap of kaolinite from typically between 4.9 and 8.

A novel route for preparation of chemically activated carbon from pistachio wood for highly efficient Pb(II) sorption.

Pistachio wood-derived activated carbon prepared by a two-stage process (PWAC-2), conducting two consecutive chemical activation processes with NHNO and NaOH, respectively. The results showed that explosive characteristic of NHNO can primarily be employed to produce a char, with a large surface area and a highly-ordered pore structure, which can be subjected to a second activation process with NaOH to prepare a more suitable activated carbon, with a highly porous structure and useful functional groups, for removal of lead ions from aqueous media. An L Taguchi experimental design was used by varying impregnation ratio, activation time and temperature in both pre- and post-activation stages, and the results showed that, in both stages, a small activating agent/precursor and a proportional low activation time suffice for preparation of an advantageous activated carbon for Pb(II) adsorption.

New micro/mesoporous nanocomposite material from low-cost sources for the efficient removal of aromatic and pathogenic pollutants from water.

A new micro/mesoporous hybrid clay nanocomposite prepared from kaolinite clay, seeds, and ZnCl via calcination in an inert atmosphere is presented. Regardless of the synthesis temperature, the specific surface area of the nanocomposite material is between ≈150 and 300 m/g. The material contains both micro- and mesopores in roughly equal amounts.

Disinfection of water with new chitosan-modified hybrid clay composite adsorbent.

Hybrid clay composites were prepared from Kaolinite clay and seeds via modification with chitosan, Alum, NaOH, and ZnCl in different ratios, using solvothermal and surface modification techniques. Several composite adsorbents were prepared, and the most efficient of them for the removal of gram negative enteric bacteria was the hybrid clay composite that was surface-modified with chitosan, Ch-nHYCA (Chitosan: nHYCA = 1:5). This composite adsorbent had a maximum adsorption removal value of 4.

Adsorptive removal of 2,4,6-trichlorophenol in aqueous solution using calcined kaolinite-biomass composites.

Synergistically combined low-cost composites may be effective for the potential treatment of effluents containing organic pollutants. Hence, preparation of Carica-papaya-modified-kaolinite (CPK) and pine-cone-modified-kaolinite (PCK) composites via calcination of pure kaolinite (KAC), Carica-papaya and pine-cone seeds is demonstrated. The composites' specific surface areas were reduced by more than 57% but no structural modification in KAC lattice d-spacing, indicating impregnation of calcined biomass on clay surfaces and pores.

Hybrid materials from agro-waste and nanoparticles: implications on the kinetics of the adsorption of inorganic pollutants.

This study is a first-hand report of the immobilization of Nauclea diderrichii seed waste biomass (ND) (an agro-waste) with eco-friendly mesoporous silica (MS) and graphene oxide-MS (GO + MS) nanoparticles, producing two new hybrid materials namely: MND adsorbent for agro-waste modified with MS and GND adsorbent for agro-waste modified with GO + MS nanoparticles showed improved surface area, pore size and pore volume over those of the agro-waste. The abstractive potential of the new hybrid materials was explored for uptake of Cr(III) and Pb(II) ions. Analysis of experimental data from these new hybrid materials showed increased initial sorption rate of Cr(III) and Pb(II) ions uptake.

Kinetics and thermodynamics of heavy metal ions sequestration onto novel Nauclea diderrichii seed biomass.

This study reports the sequestration of Cd(II) and Hg(II) using a new biosorbent, Nauclea diderrichii seed biomass. Experimental data obtained were fitted into kinetic and thermodynamic models. Experimental data fitted best into pseudo-second order kinetic model among others.

Kinetic and thermodynamics of the removal of Zn2+ and Cu2+ from aqueous solution by sulphate and phosphate-modified Bentonite clay.

The modification of pristine Bentonite clay with sulphate and phosphate anions was found to increase its cation-exchange capacity (CEC), adsorption capacity and overall pseudo-second order kinetic rate constant for the adsorption of Cu(2+) and Zn(2+). Modification with sulphate and phosphate anion decreased the specific surface area of pristine Bentonite clay. Phosphate-modified Bentonite clay was found to give the highest adsorption capacity for both metal ions.

Modeling of fixed-bed column studies for the adsorption of cadmium onto novel polymer-clay composite adsorbent.

Kaolinite clay was treated with polyvinyl alcohol to produce a novel water-stable composite called polymer-clay composite adsorbent. The modified adsorbent was found to have a maximum adsorption capacity of 20,400+/-13 mg/L (1236 mg/g) and a maximum adsorption rate constant of approximately = 7.45x10(-3)+/-0.