Levels of selected metals in teff grain samples collected from three different areas of  Ethiopia by microwave plasma-atomic emission spectroscopy

The levels of selected essential and non-essential metals in the white, red, and mixed teff grains collected from Bure, Debre Markos and Bahir Dar (Ethiopia) were determined by microwave plasma-atomic emission spectroscopy (MP-AES). After proper sample pretreatment, the powdered teff was wet digested with the acid mixture (5 mL HNO3:1 mL HClO4) at 240 oC for 2:30 h over Kjeldhal digestion block. The accuracy of the optimized procedure was evaluated by analyzing the digest of the spiked samples with a standard solution of metals, and the percentage recoveries varied from 92% to 104%. The mean concentrations of metals determined (mg/kg, dry weight) were in the ranges of Al (713-1513) > Fe (252-1195) > Ca (233-348) > Zn (69-102) > Mn (20-45) > Cu (13-15) > Pb (1.8-2.8) > Cd (0.8-1.8). In this study, Al and Cd were determined in the teff for the first time. Analysis of variance indicated no significant difference between the mean concentrations of Cu and Mn among the white teff samples, Mn among the red teff samples and Cd and Pb among the mixed teff samples, but there was a significant difference for the other studied metals among the corresponding teff samples at 95% confidence level. KEY WORDS: Teff grain, Eragrostistef (Zucc.) Trotter, Essential metals, Non-essential metals, Ethiopia Bull. Chem. Soc. Ethiop. 2020, 34(3), 449-462. DOI: https://dx.doi.org/10.4314/bcse.v34i3.2

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Levels of selenium in selected river, well and bottled waters in Ethiopia by microwave plasma-atomic emission spectrometry

Bulletin of the Chemical Society of Ethiopia ◽

10.4314/bcse.v34i2.1 ◽

2020 ◽

Vol 34 (2) ◽

pp. 215-226

Author(s):

A. Minuye ◽

F. Zewge ◽

B. S. Chandravanshi

Keyword(s):

Emission Spectroscopy ◽

Microwave Plasma ◽

Tap Water ◽

Selenium Deficiency ◽

Atomic Emission ◽

Atomic Emission Spectroscopy ◽

Emission Spectrometry ◽

Plasma Atomic Emission ◽

Plasma Atomic Emission Spectrometry ◽

Significant Difference

Selenium is an essential trace element for many organisms, including humans, but it is toxic at higher level than homeostatic levels. Both selenium deficiency and toxicity are problems around the world (specially in China, India, USA). The level of selenium in selected waters of Ethiopia (including Akaki Kality river and some of its tributaries such as Kebena, Saris Abo, and Estifanos areas; bottled waters like Yes, Aqua Safe and Gift; well waters like Ziqualla Wogem, Akaki Kality and Ferensay Legasion; and tap water at Arat Kilo) were determined by microwave plasma-atomic emission spectroscopy after wet digestion and acidification. The levels selenium determined (µg/L) were 7.0, 3.1, 6.4, 3.9, 6.3, 5.0, 5.4, 0.66, 4.2, 6.3, and 2.0, respectively. The percentage recovery of Se was found to be 95.2% which is in the acceptable range. The ANOVA result showed that there is a significant difference between the mean levels of selenium in the river, well and bottles waters. The results obtained in this study were compared with the permissible limit (10 µg/L) set by Ethiopian Standards Agency and the tolerable level set by WHO (< 40 µg/L). Thus the levels of selenium detected in this study are within the recommended limit. KEY WORDS: Selenium, Trace metal, Water samples, Microwave plasma-atomic emission spectroscopy, Ethiopia Bull. Chem. Soc. Ethiop. 2020, 34(2), 215-226. DOI: https://dx.doi.org/10.4314/bcse.v34i2.1

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Microsampling in graphite cup capacitively coupled microwave plasma atomic emission spectroscopy

Spectrochimica Acta Part B Atomic Spectroscopy ◽

10.1016/0584-8547(91)80115-j ◽

1991 ◽

Vol 46 (8) ◽

pp. 1207-1214 ◽

Cited By ~ 9

Author(s):

Abdalla H. Au ◽

Kin C. Ng ◽

James D. Winepordner

Keyword(s):

Emission Spectroscopy ◽

Microwave Plasma ◽

Atomic Emission ◽

Atomic Emission Spectroscopy ◽

Plasma Atomic Emission ◽

Capacitively Coupled

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Analysis of Mercury in Skin Lightening Cream by Microwave Plasma Atomic Emission Spectroscopy (MP-AES)

Molecules ◽

10.3390/molecules26113130 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3130

Author(s):

Hardoko I. Qudus ◽

Purwadi Purwadi ◽

Iis Holilah ◽

Sutopo Hadi

Keyword(s):

Emission Spectroscopy ◽

Microwave Plasma ◽

Atomic Emission ◽

Atomic Emission Spectroscopy ◽

Solution Stability ◽

Analysis Method ◽

Plasma Atomic Emission ◽

Relative Standard ◽

The Stability ◽

Skin Lightening

This research aimed at developing an analysis method, which was optimized and validated to determine the content of mercury in skin lightening cream discovered in the market in Bandar Lampung, Indonesia, through the use of microwave plasma atomic emission spectroscopy (MP-AES). The optimization on the analysis method was conducted on pump rate, viewing position, and reductant concentration in order to obtain the highest mercury emission intensity, while the solution stability was optimized to know the stability of mercury in the solution. The result showed that the method developed had precision with a relative standard deviation of 2.67%, recovery value of 92.78%, and linearity with an r value of 0.993, respectively. The sensitivity of the instrument detection had a limit of analysis method detection and quantification of 0.59 and 1.98 µg/L, respectively. The results of the test of the lightening cream (8 of 16 samples) positively contained mercury in the range of 422.61–44,960.79 ng/g. Therefore the method of analysis developed may be used for routine analysis of chemicals in any cosmetics products.

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