Dust fallout can have diverse impacts ranging from major health problems to environmental concerns. It can harbour disease-causing microorganisms and toxic heavy metals, and it is therefore critical to establish the m...Dust fallout can have diverse impacts ranging from major health problems to environmental concerns. It can harbour disease-causing microorganisms and toxic heavy metals, and it is therefore critical to establish the microbial and the mineral compositions of the dust fallout in a particular site and elucidate the possible related health implications for humans and the entire environment. In this study, dust fallout samples were collected from Arandis, a town in the Erongo region (Namibia), using the American Society for Testing and Materials standard method (ASTM D1739) for collection and analysis of dust fallout (settleable particulate matter). The identification of present viable bacteria was done through culturing and isolation techniques and the morphological characteristics, and the elemental composition of the dust fallout were determined using the Stereomicroscope and the X-ray fluorescence, respectively. The results showed that the most dominant bacteria contained in the fallout dust were the Bacillus species. The morphological characterisation revealed that the present particles were mixed black, brownish, greenish, and crystal particles with irregular, cubical, flocks and flake shapes. The elemental investigations indicated that the dust fallout contained Hg, As, Fe, Ni, Cr, Mn, Al and Pb occurring in varying concentrations and the status of pollution of the dust fallout ranged from low to severe concerning the inconsistent heavy metal indices that are the contamination factor, pollution load index and the enrichment factor.展开更多
The anthill soil is used by hypertensive elderly and teenagers from Oshikoto region (Namibia) and many of them testified stabilization of their blood pressure to normal after consuming the anthill soil-derived aqueous...The anthill soil is used by hypertensive elderly and teenagers from Oshikoto region (Namibia) and many of them testified stabilization of their blood pressure to normal after consuming the anthill soil-derived aqueous extracts. This study therefore investigated and/or assessed the physicochemical parameters, the contents of some metal(loid)s (and their associated potential health risks) and the qualitative composition of bioactive compounds of this anthill soil. The homogenous soil sample collected from various anthill soils in the Oshikoto region was used to obtain the measurements of physiochemical parameters. The elemental contents were determined (using an Inductively Coupled Plasma Optical Emission Spectrophotometer) after acid digestion in accordance with the EPA method 350B and their potential health risk assessments were performed. Methanol, aqueous methanol, and aqueous-based extracts were generated via maceration extraction process prior to the screening of bioactive compounds using standard diagnostic assays. The oxidation reduction potential (164.4 ± 16.6 mV) was the only physicochemical parameter whose value was within the World Health Organization limits for drinking water whereas, total dissolved solids (23 ± 5.5 mg/L), electrical conductivity (44 ± 10.1 uS/cm) and pH (5.35 ± 0.33) were out of specifications. Phenolic compounds, flavonoids, terpenoids, and cardiac glycosides were present in anthill soil (with respect to the extractants used) to which its antihypertensive properties can be attributed in addition to some of the studied mineral components. With respect to the pH, TDS and EC, and the contents of most metal(loid)s in relation to their health risk assessment values, the results suggest that aqueous extracts derived from this anthill soil can be deemed unsuitable for human consumption.展开更多
文摘Dust fallout can have diverse impacts ranging from major health problems to environmental concerns. It can harbour disease-causing microorganisms and toxic heavy metals, and it is therefore critical to establish the microbial and the mineral compositions of the dust fallout in a particular site and elucidate the possible related health implications for humans and the entire environment. In this study, dust fallout samples were collected from Arandis, a town in the Erongo region (Namibia), using the American Society for Testing and Materials standard method (ASTM D1739) for collection and analysis of dust fallout (settleable particulate matter). The identification of present viable bacteria was done through culturing and isolation techniques and the morphological characteristics, and the elemental composition of the dust fallout were determined using the Stereomicroscope and the X-ray fluorescence, respectively. The results showed that the most dominant bacteria contained in the fallout dust were the Bacillus species. The morphological characterisation revealed that the present particles were mixed black, brownish, greenish, and crystal particles with irregular, cubical, flocks and flake shapes. The elemental investigations indicated that the dust fallout contained Hg, As, Fe, Ni, Cr, Mn, Al and Pb occurring in varying concentrations and the status of pollution of the dust fallout ranged from low to severe concerning the inconsistent heavy metal indices that are the contamination factor, pollution load index and the enrichment factor.
文摘The anthill soil is used by hypertensive elderly and teenagers from Oshikoto region (Namibia) and many of them testified stabilization of their blood pressure to normal after consuming the anthill soil-derived aqueous extracts. This study therefore investigated and/or assessed the physicochemical parameters, the contents of some metal(loid)s (and their associated potential health risks) and the qualitative composition of bioactive compounds of this anthill soil. The homogenous soil sample collected from various anthill soils in the Oshikoto region was used to obtain the measurements of physiochemical parameters. The elemental contents were determined (using an Inductively Coupled Plasma Optical Emission Spectrophotometer) after acid digestion in accordance with the EPA method 350B and their potential health risk assessments were performed. Methanol, aqueous methanol, and aqueous-based extracts were generated via maceration extraction process prior to the screening of bioactive compounds using standard diagnostic assays. The oxidation reduction potential (164.4 ± 16.6 mV) was the only physicochemical parameter whose value was within the World Health Organization limits for drinking water whereas, total dissolved solids (23 ± 5.5 mg/L), electrical conductivity (44 ± 10.1 uS/cm) and pH (5.35 ± 0.33) were out of specifications. Phenolic compounds, flavonoids, terpenoids, and cardiac glycosides were present in anthill soil (with respect to the extractants used) to which its antihypertensive properties can be attributed in addition to some of the studied mineral components. With respect to the pH, TDS and EC, and the contents of most metal(loid)s in relation to their health risk assessment values, the results suggest that aqueous extracts derived from this anthill soil can be deemed unsuitable for human consumption.
