Health Implications of Occupational Exposure of Butchers to Emissions from Burning Tyres

Background: Flames from burning scrap tyres are used in de-furring animals for human consumption in most parts of Nigeria. Emissions from tyres are known to contain a myriad of toxic mixtures especially particulate matter (PM), volatile organic compounds, hazardous air pollutants, and inspirable metals, some of which are known human carcinogens. This cross-sectional study investigated the deleterious health effects of these emissions in occupationally-exposed workers at the Dei-Dei Abattoir, Abuja, Nigeria. Methods: A total of 156 respondents were divided into two groups. Group 1 (124 butchers) and group 2 [32 administrative staff (AS)]. Data from digital spirometry were used to determine the association between chronic exposure to tyre emissions and lung function. Urinary 1-Hydroxypyrene concentration, phenolic compounds levels and heavy metal concentrations were determined. Also ambient PM and polycyclic aromatic hydrocarbons (PAHs) concentrations at 3 delineated points in the abattoir were measured. Findings: Spirometry results showed significant deterioration of lung function in the butchers. The concentration of 1-Hydroxypyrene (μg/molCret) in the post-shift urine samples of the butchers was significantly higher (P < 0.05) in butchers relative to the AS (0.52 ± 0.13 Vs 0.20 ± 0.07, respectively). Similarly the concentrations of zinc and nickel (mg/l) were significantly higher in the butchers compared to the AS (zinc: 0.91 ± 0.19 Vs 0.31 ± 0.28, respectively; nickel: 0.11 ± 0.06 Vs 0.06 ± 0.02, respectively). Anthracene, fluoranthene, pyrene, benzo-a- pyrene, and PM concentrations were significantly higher at the de-furring point when compared to the wash bay and the administrative building, especially between 8.00 and 8.30 am. Conclusion: Occupational exposure to scrap tyre emissions resulted in significant adverse health effects. The existing laws banning the use of burning tyres in meat processing should be enforced while the use of personal protective equipment should be encouraged in abattoirs

Identification of neurotherapeutic constituents in Ocimum gratissimum with cholinesterase and mono amine oxidase inhibitory activities, using GC-MS analysis, in vitro, and in silico approaches

Neuroprotective activities of various extracts of Ocimum gratissimum (OG), have been reported, but there is paucity of information on its neurotherapeutic constituents. This study is aimed at identifying the neurotherapeutic constituents in OG leaves using in vitro assays, GC-MS chemical investigation and in silico studies including molecular docking, ensemble-based docking, molecular dynamics (MD) simulation, clustering and ADMET filtering analysis. Methanol extract of O gratissimum (MEOG) and solvent-partition (n-hexane, ethylacetate, and methanol residue fraction) of MEOG were investigated for in vitro acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and monoamine oxidase B (MAO-B) inhibition at concentration of 0.65, 12.5, 2.5, 5, and 10 mg/mL, using donepezil, phenazine methosulfate and selegiline as reference inhibitors for AChE, BChE and MAO B respectively. n-hexane solvent partition fraction was further investigated using GC-MS analysis. Identified compounds were screened against human AChE, BChE and MAO-B activities using molecular docking and molecular dynamics. The lead phytochemicals were further analysed for ADMET in silico analysis. MEOG and the 3 fractions (n-hexane, ethylacetate, and methanol residue fraction) inhibited the activities of AChE, BChE and MAO-B in a concentration-dependent manner with AChE (IC50 = 2.380, 2.022, 2.066 and 1.079 mg/mL respectively), BChE (IC50 = 2.261, 2.126, 2.630 and 1.465 mg/mL respectively) and MAO-B (IC50 = 2.345, 1.584, 2.933 and 2.935 mg/mL respectively). From the 38 GC-MS identified compounds, 7 hit compounds were further subjected to ensemble-docking, the lead phytochemicals (LP): cholestane and 3-methoxy-morphanin presented highest multiple binding tendencies to the three enzymes. Cholestane had the highest binding energies of −9.9, −9.0 and −11 kcal/mol, while 3-methoxy-morphanin presented the second-best binding energies of −9.3, −8.2 and −10.1 kcal/mol respectively. When compared with the binding pattern of reference inhibitors of the enzyme, lead phytochemicals were orientated in the catalytic sites of the enzyme and interacted with important catalytic residues. The LP-enzyme complexes were stable during the MD simulation analysis. Cholestane and 3-methoxy-morphanin presented favorable ADMET properties over several molecular descriptors and filters, with druggable properties and ability to cross the blood-brain barrier. Hence, cholestane and 3-methoxy-morphanin, in part, or in synergy with other hit phytochemicals, may be responsible for the neurotherapeutic activities of MEOG leaves

Chronic toxicological evaluation and reversibility studies of Moringa oleifera ethanolic seed extract in Wistar rats

This study evaluated the chronic toxicity and reversibility Potential of Moringa oleifera seed in Rats. Forty-four Wistar rats were randomized into four groups of 11 rats each, three groups were treated with doses of 50, 200, and 800 mg/kg of MOESE p.o, for 90 days while one group served as control and was administered distilled water p.o. After 90 days, half of the animals were sacrificed and blood samples collected for determination of biochemical and haematological parameters; antioxidants and malondialdehyde (MDA); sperm count, motility and morphology. Organs were harvested for weight determination and histopathological assessments the liver. The other half were left for another 30 days without treatment with the extract, after which they were sacrificed. MOESE produced significant reduction in food and water intake, relative weights of liver, heart, testes, lung and spleen at all treatment dose, these changes were overall small magnitude, within the range of historical control. There was significant increase in AST (200 and 800 mg/kg), LDH (200 mg/kg), ALP (800 mg/k), albumin (800 mg/kg) and K+ (800 mg/kg), but decrease in serum Ca2+ (50 and 200 mg/kg). A significant increase in serum antioxidant was observed at all treatment doses, while semen pH were reduced. These effects on organ relative weights and all biochemical parameters except AST and ALP were reversed after 30 days of the reversibility study. Histopathological presentations showed necrosis in the liver (50 and 200 mg/kg). Our study demonstrated that ethanol extract of Moringa oleifera seeds could cause infertility in male rats due to decreased semen pH. Our results also showed that the extract may be hepatotoxic due to persistent high level of AST and ALP even after cessation of exposure to the extract, this is also consistent with the histopathological results that shows hepatic necrosis associated with chronic exposure to the extract.Keywords: Moringa oleifera seed, Toxicity, Wistar Rat