Microwave Digestion System Research Articles

Chemical sample preparation of plant materials in tunnel-type microwave digestion systems for elemental analysis

Analyzing plant materials is essential for environmental monitoring, analytical control of food products, and medicinal raw materials. A review of global practices has shown that there are still no standard proceedings for chemical sample preparation suitable for all plant types without restrictions on the range of elements determined. Creating a standardized scheme for plants is feasible, as the macro composition of any plants consists of at least 90% organic compounds (cellulose, protein, lipids, etc.), whose mineralization results in the formation of water and a gaseous phase. In this study, certified plant samples were mineralized in a tunnel-type microwave digestion system MultiVIEW (SPC SCIENCE, Canada) with variations in analytical sample sizes, composition and volume of reagents, options for adding the reaction mixture, and vessel heating modes for simultaneous determination of a wide range of elements using inductively coupled plasma atomic emission spectrometry. The completeness of dissolution (the degree of correspondence between found and certified contents) was used as one of the criteria for the optimality of sample preparation conditions. It was shown that with a three-stage heating regime of the vessels (heating rate at the first stage 2.76 оC/min) with a sample weight of 0.5 g and separate sequential addition of the reaction mixture (4 ml HNO3, 1.5 ml H2O2, 1 ml HCl, and 0.05 ml HF), it is possible to reliably determine typical plant contents of Si, Al, Mg, Ca, Fe, Na, K, Ba, Sr, Rb, P, B, Mn, Ti, Ni, V, Cu, Zn.

Determination of sodium and potassium in Dan Hong injection by atomic absorption spectrometry

To establish and validate the determination method of the content of sodium ion and potassium ion in Dan Hong injection by atomic absorption spectrometry (AAS). [Methods] Microwave digestion system was applied to deteriorate samples, and the content of sodium ion and potassium ion was determined by AAS. [Results] The calibration curve of sodium was liner (r=0.9998) in the range from 0.1to0.6mg/L. The average recovery was 101.1% with RSD 1.8%. The limit of detection was 5.3μg/L. The calibration curve of potassium was liner (r=0.9998) in the range from 0.1 to 0.8mg/L. The average recovery was 99.8%with RSD 2.3%. The limit of detection was 7.7μg/L. The determination results of 10 batches Dan Hong injection sample showed that the content of sodium ion was 562.3 to 734.7 mg/L and potassium ion was 206.9 to 314.4mg/L. [Conclusion] The method is simple and accurate and can be used for determination of the contents of sodiumion and potassium ion in Dan Hong injection. The accurate quantitative determination method can be promoted to quality control of Dan Hong injection

Seasonal Variation of Heavy Metals in the Bivalves of a Major Fish Landing Centre in Mumbai

One of the most prevalent environmental contaminants found in aquatic ecosystems and its associated biota is considered to be heavy metals. The current study evaluated the heavy metal concentrations of Copper (Cu), Iron (Fe), Cadmium (Cd), Zinc (Zn), Manganese (Mn), Cobalt (Co), Chromium (Cr), Arsenic (As), Nickel (Ni), and Lead (Pd) in the soft tissues of M.casta and Paphia malabarica species seasonally for one year. The soft tissue of the two species were digested using a microwave digestion system (CEM-MARS-5) using nitric acid and perchloric acid. Evaluation of Cu, Ni, Cr, Mn, Co, Fe, and Zn was done using ICP-OES while for estimation of Pd, Cd and As, ICP-MS was used. During the study, Fe, Mn and Zn content dominated the whole soft tissues of both species. The findings demonstrated that the pre-monsoon season had higher amounts of the most examined heavy metals, whereas the monsoon season had the lowest quantities of these metals in the soft tissues of both species.

#2651 Microwave tissue digestion and flame atomic absorption spectroscopy for measuring tissue sodium content in CKD patients

Abstract Background and Aims Skin and muscle sodium accumulation has been demonstrated in CKD patients and may contribute to progression of the disease. Various methods are available for measuring tissue sodium content. However, the accuracy and reproducibility of these methods remain unknown. Dry ashing is the most used digestion method, but is expensive, time consuming and has a risk of incomplete digestion. This study compared microwave digestion, dry ashing, and two electrolyte quantification methods for quantifying tissue sodium and potassium. Method We compared microwave digestion (Ethos LEAN Compact Microwave Digestion System, Milestone SRL) and dry ashing (Nabertherm S27) as sample preparation methods, and flame atomic absorption spectroscopy (FAAS, Model 425 Flame Photometer, Sherwood Scientific) and inductively coupled plasma optical emission spectrometry (ICP-OES, Varian 720-ES, Varian Inc.) as electrolyte quantification methods. Skin and muscle samples were obtained from rats and mice, and human skin samples were used. Tissues biopsies were cut in three pieces and digested separately. The methods were compared using interclass correlation coefficient (ICC) and Bland-Altman analysis. The third piece of tissue was microwave-digested by another operator to test inter-operator reproducibility by calculating the ICC and absolute overall mean difference. Results With microwave digestion and FAAS median (IQR) human skin concentration was 114.8 (99.2-157.0, n = 12) mmol/L, confirming tissue sodium storage. When including all tissues, FAAS and ICP-OES showed high agreement for sodium (ICC 0.98, bias –0.00008 mmol/g, n = 141 and potassium (ICC 0.98, bias –0.005 mmol/g, n = 141). Microwave digestion and ashing showed agreement for sodium (ICC 0.93, bias –0.002 mmol/g, n = 61) and potassium (ICC 0.93, bias –0.02 mmol/g, n = 61). The inter-operator agreement was good for sodium (ICC 0.95, absolute mean difference (SD) 0.044 mmol/g (0.073), n = 70) and potassium (ICC 0.96, absolute mean difference (SD) 0.031 mmol/g (0.032), n = 70). Conclusion Microwave digestion with FAAS is a reliable and consistent method for sodium and potassium trace analysis in animal and human tissues compared to ashing and ICP-OES, respectively. This method showed more quantification of cations than the most frequently reported method, representing an easier, and less time-consuming way to quantify tissue sodium in CKD research.

MICROWAVE TISSUE DIGESTION AND FLAME ATOMIC ABSORPTION SPECTROSCOPY FOR MEASURING TISSUE SODIUM CONTENT IN HYPERTENSIVE AND CARDIOVASCULAR RISK PATIENTS

Objective: Skin sodium accumulation has been demonstrated in hypertensive patients and may contribute to the pathophysiology of hypertension. Various methods are available for measuring tissue sodium content. However, the accuracy and reproducibility of these methods remain unknown. Dry ashing is the most used digestion method, but is expensive, time consuming and has a risk of incomplete digestion. This study compared microwave digestion, dry ashing, and two electrolyte quantification methods for quantifying tissue sodium and potassium. Design and method: We compared microwave digestion (Ethos LEAN Compact Microwave Digestion System, Milestone SRL) and dry ashing (Nabertherm S27) as sample preparation methods, and flame atomic absorption spectroscopy (FAAS, Model 425 Flame Photometer, Sherwood Scientific) and inductively coupled plasma optical emission spectrometry (ICP-OES, Varian 720-ES, Varian Inc.) as electrolyte quantification methods. Skin and muscle samples were obtained from rats and mice, and human skin samples were used. Tissues biopsies were cut in three pieces and digested separately. The methods were compared using interclass correlation coefficient (ICC) and Bland-Altman analysis. The third piece of tissue was microwave-digested by another operator to test inter-operator reproducibility by calculating the ICC and absolute overall mean difference. Results: With microwave digestion and FAAS median (IQR) human skin concentration was 114.8 (99.2-157.0, n=12) mmol/L, confirming tissue sodium storage. When including all tissues, FAAS and ICP-OES showed high agreement for sodium (ICC 0.98, bias -0.00008 mmol/g, n=141 and potassium (ICC 0.98, bias -0.005 mmol/g, n=141). Microwave digestion and ashing showed agreement for sodium (ICC 0.93, bias -0.002 mmol/g, n=61) and potassium (ICC 0.93, bias -0.02 mmol/g, n=61). The inter-operator agreement was good for sodium (ICC 0.95, absolute mean difference (SD) 0.044 mmol/g (0.073), n=70) and potassium (ICC 0.96, absolute mean difference (SD) 0.031 mmol/g (0.032), n=70). Conclusions: Microwave digestion with FAAS is a reliable and consistent method for sodium and potassium trace analysis in animal and human tissues compared to ashing and ICP-OES, respectively. This method showed more quantification of cations than the most frequently reported method, representing an easier, and less time-consuming way to quantify tissue sodium in hypertension and cardiovascular research.

Comparative analysis of rare earth elements concentrations in domestic dogs and Apennine wolves of Central Italy: Influence of biological, nutritional, and lifestyle factors

Rare Earth Elements (REEs) are strategical elements playing a crucial role in the industry, especially in producing high-tech materials. Therefore, REEs are new contaminants of emerging concerns. However, due to the lack of exposure data on REE occurrence in environmental matrices, especially in European countries, it is still tricky to establish environmental background levels to assess the ecotoxicological risk related to REEs exposure. The present study aimed to evaluate the liver concentrations of REEs in domestic dogs (Canis lupus familiaris) and Apennine wolves (Canis lupus italicus) living in the Abruzzo region, Italy. Moreover, for the scope of the present study, the dog's group was divided according to their sex, age, lifestyle, and diet. Wolves were categorized concerning their sex and genetic characteristics. Liver samples from dogs and wolves were collected during diagnostic necropsies from carcasses, sample mineralization was performed by a microwave digestion system with a single reaction chamber, and simultaneous determination of the presence of REEs was performed by Inductively Coupled Plasma Mass Spectrometer (Q-ICP-MS) using standard mode for all rare earth elements except scandium (Sc) which was acquired in kinetic energy discrimination (KED) mode. Hepatic concentrations of REEs were statistically significantly higher in wolves compared to dogs. Moreover, significant differences in REEs concentrations arose also from the genetic type of wolf, since “pure wolves” had higher liver concentrations of REEs compared to wolf-dog hybrids. Female and adult dogs also showed elevated REEs compared to male and juvenile dogs, while no significant differences were demonstrated for dogs' diet and lifestyle. The results of the present study confirm the exposure of domestic and wild carnivores to REEs, showing also the ability of REEs to accumulate in carnivore livers, suggesting the potential role of this species as an alternative bioindicator.

RETRACTED ARTICLE: Inductively coupled plasma-mass spectrometry (ICP-MS) detection of trace metal contents of children cosmetics

Consumption of cosmetic products in daily life in order to improve skin quality or appearance is becoming quite common. Over time, it may expose consumers to skin problems and effects caused by the absorption of chemical elements. Clean cosmetic production is important for our health. However, heavy metals can be found as impurities in raw materials or as by-products of the cosmetic production process. Women's ingestion and exposure to organic and inorganic contaminants in cosmetics through dermal absorption, due to reasons such as personal habits and characteristics of the living environment, may contribute to carcinogenic risks following daily dietary exposure. NCS ZC 81002b (Human Hair) was performed as a certified reference material in method validation. This work was conducted to evaluate element concentrations of selected elements (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Hg, Cd and Pb) in 3 different brands of children's cosmetic products such as bright and colorful 22 eye shadows (7 different colour) 4 lipsticks (3 different colour) and 4 nail polishes (3 different colour) used by children in Turkey. The sample solutions were analyzed with the inductively coupled plasma mass spectrometry (ICP-MS) technique after the microwave digestion system. Consequently, the highest concentration of Al used as pigment was found in the eye shadow, lipstick and nail polish samples for the 3 brands, while the Se concentrations were the lowest in lipstick samples. The results of As, Cd, Hg, Pb, which are restricted or banned for use in cosmetic products in most countries, are below the limits set by the Food and Drug Administration (FDA) and Health Canada Product Safety Laboratory (PSL).

Comparison between Microwave Digestion and Conventional Open Digestion Method for Heavy Metals determination

In the present study a comparison between microwave assisted digestion and conventional wet acid open digestion system for dissolution of bivalve tissue samples was carried out. Sample matrix decomposition was done by using a mixture of concentrated nitric acid and hydrogen peroxide. The determination of trace elements (Zn, Co, Cu, Cd and Pb) in commercially popular bivalve species from two important fish landing centers in Mumbai was used for this purpose. The recovery of heavy metals after analysis was done using certified reference material TORT 2- Lobster hepatopancreas for both the digestion methods. The results of the present study indicate that microwave digestion system for heavy metal analysis is the preferred method for rapid and good quality results. It provides better recovery and precision for heavy metal analysis. The sample preparation step is much easier by microwave digestion system compared to conventional open digestion methods for heavy metal analysis. It is particularly ideal for trace metals like lead and cadmium as they are generally present in very small concentration in biological samples. In the current study microwave digestion proved to be better method than conventional open digestion method with rapid sample digestion process and least sample contamination problem.

Determination of heavy metals in Iranian food packaging plastic

Dissemination of End-users to heavy metal is a salient issue where many researchers have been attentive on this subject for decades. These Metals can unfurl the Human Body via food contact consumption. So this research aims to investigate the content of heavy metals (lead, cadmium, chromium, iron, cobalt, copper, barium nickel, zinc, and arsenic has been determined in thirty-two different Iranian plastic food packaging containers by using Inductive-coupled plasma optical emission spectroscopy (ICP-OES) using Microwave digestion system. In Adding to that, The Investigated packed materials like which Includes Dairy Products, mayonnaises, and kinds of ketchup. The Results ended up claiming heavy metals ranges are Pb(0.018-1258 mg/kg), Cu(0.41-31.13 mg/kg), Ni(0.06-0.866 mg/kg), Zn(7.27-88.69 mg/kg), Fe(4.7-901.6 mg/kg), Cr(0.87- 273.13 mg/kg), Cd(0.003-0243 mg/kg), Co (LDL - 0.358 mg/kg) and As(0.017-0.387 mg/kg). Lead (Pb) was detected at concentrations of 0.018-1258 mg/kg in eight of 32 packages. The highest concentrations were detected for Lead in the yellow and green-colored samples.

Total Triterpenes, Polyphenols, Flavonoids, and Antioxidant Activity of Bioactive Phytochemicals of Centella asiatica by Different Extraction Techniques.

Obtaining phytochemical-rich plant extracts from natural products where the active ingredients are present in comparatively low levels in the tissue matrix is the critical initial step of any chemical analysis or bioactivity testing. The plant C. asiatica is rich in various phytochemicals, the major constituents being triterpenes and flavonoids, as well as other polyphenols, leading to a number of bioactivities. In this study, an attempt was made to achieve several green technology principles, while optimizing the extraction method for the efficient extraction of bioactive compounds from C. asiatica. Soxhlet extraction (SE), ultrasound-assisted extraction (UAE) with low-frequency sonication, microwave-assisted extraction (MAE) using a closed-vessel microwave digestion system, and subcritical water extraction (SWE) in a high-pressure reactor were employed to extract the bioactive compounds. The solvent system, extraction time, and solid-to-solvent ratio were varied to optimize the extraction. UAE gave the best extraction yield, while MAE gave similar results, with a solid-to-liquid ratio of 1:25, a binary solvent system of 9:1 methanol to water (v/v), and a 20 min extraction time for the extraction of triterpenes, including madecassoside, asiaticoside, madicassic acid, and asiatic acid. Investigation of different solvent systems based on water and methanol also revealed information on the extraction behavior of total triterpene content (TTC), total polyphenolic content (TPC), total flavonoid content (TFC), and the variations in the antioxidant capacity of the extracts. In this study, it was evident that UAE and MAE offer more efficient and effective extraction of bioactive compounds in terms of extraction yield, time, and minimal solvent and energy use. Furthermore, the results showed that the different solvent ratios in the extraction mixture will affect the extraction of bioactive compounds, and a binary solvent system with a combination of methanol and water was the most efficient for the studied compounds in Centella asiatica.

Nutritional Composition of House Cricket (Acheta domesticus) and Dung Beetle Larva (Oryctes boas) in Osun State: Implication to Dietary Improvement in Nigeria

Background: Edible insects and the act of eating insects (Entomophagy) are common across the globe. Feeding variations and species differences, among other factors, influence these individuals’ chemical and mineral components. The current study elucidated the nutritional composition of house cricket (Acheta do-mesticus) and dung beetle larva (Oryctes boas) collected in Osun State, Southwestern Nigeria. Methods: The nutritional composition of the two species of insects sampled randomly was determined following standard methods of the Association of Official Analytical Chemists. The ground crickets and beetle larvae were digested with HNO3 and HCl in a microwave digestion system; inductively coupled plasma-optical emission was used to determine the amounts of Calcium, Sodium, Potassium, Phosphorus, Magnesium, Iron, Copper, Manganese, and Zinc in the samples. Following a standard procedure, the amino acid profile was performed using a Biochrom30+ amino acid analyzer (Pharmacia-Biotech, Buckinghamshire, UK). Data obtained were expressed as means ± standard deviations of triplicate analyses and compared among the two insect species using Student’s t-test at p < 0.05. Results: Generally, the nutritional components of A. domesticus were higher than that of O. boas. The O. boas was not significantly higher (P> 0.05) in Iron (6. 83 ± 1. 80 mg/100 g dry matter) but significantly high-er (P< 0.05) in Magnesium (730. 94 ± 2. 64 mg/100 g dry matter) than A. domesticus. All Essential Amino Acids (EAAs) and Non-Essential Amino Acids (NEAAs) were present in the two insect species with varying concentrations. House cricket, however, has a significantly higher (P< 0.05) Arginine, Valine, Phenylalanine, Glutamine, and Glutamic Acid than O. boas. Conclusion: The two insects under this study are edible and of great nutritional values. The results of the nutritional composition of Acheta domesticus and Oryctes boas may serve as the basis for improvement in human food and feed formulation in Nigeria

Content Estimation of the Mineral Elements (Zn, Mg, Cu, Fe, Co and Ni) in Parsley at Aleppo Region Syria by Flame Atomic Absorption Spectroscopy

Metals estimation Zn, Mg, Cu, Fe, Co and Ni in parsley grown in Syrian Aleppo City in three different areas (AlsheikhSaeed, Alwadihi, and Alramouseh) were determined by flame atomic absorption spectrometry (FAAS). The experiments were carried out using atomic absorption spectrometry after wet and microwave digestion methods, in Nitric Acid as digesting solution. The concentrations of the analyzed dried parsley samples in two digestion methods were similar for each metal, we noticed that the relative standard deviations (RSD%) was higher by wet digestion method while the value did not exceed 4.27% in microwave digestion method. The use of microwave digestion system provides a better digestion, with a short period, not exceeding ten minutes in closed containers, where the microwave digestion is not associated with contamination of the sample or laboratory.

Outdoor Air Contaminants-Heavy Metals and Associated Health Risks in Duhok-Iraq

Toxic elements in the atmosphere can cause a variety of health and environmental problems. The current work aims to assess the concentrations of heavy metals associated with the air in the Duhok city-Kurdistan Region of Iraq. For the first time a low volume sampling pump with Glass Microfiber Filter paper was used. Forty samples of air filter aerosol particles were collected from several areas in the Duhok city, during the dry and rainy seasons. Samples of air filters were prepared by a microwave digestion system and assessed by inductively coupled plasma Optical-Emission Spectrometry (ICP-OES). The average concentrations of Cr, Zn, Ni, Cd, Fe, and Pb found in 20 sites in the study area for the dry season were 0.004 mg/m3, 0.007 mg/m3, 0.003 mg/m3, 0.002 mg/m3, 0.142 mg/m3, and 0.402 mg/m3 respectively. Also, the average levels of the mentioned elements were 0.003 mg/m3, 0.004 mg/m3, 0.012 mg/m3, 0.003 mg/m3, 0.138 mg/m3, and 0.645 mg/m3 respectively in wet season. Seasonal results confirmed no significant differences in the concentrations of elements measured at all study sites, with the exception of lead, which doubles during the rainy season. Results showed that the levels of metal concentrations in the present study exceeded the standard limits of WHO. The results of the health risk assessment showed that the population in Duhok city had a higher lifetime chance of developing cancer as a result of these air concentrations and their heavy metal content.

Determination of lead and cadmium in fruit juice: occurrence and risk characterisation in Iranian population

ABSTRACT In the present study, cadmium (Cd) and lead (Pb) were monitored in different juice samples including orange, grape, apple and multi-fruit juices collected from Zanjan, Iran. The collected fruit juice samples were digested by using a microwave digestion system and their metals content was determined under graphite furnace atomic absorption spectrometry (GFAAS). In addition, carcinogenic and non-carcinogenic risk resulting from Cd and Pb entered through fruit juice consumption were evaluated. Cd and Pb were detected in more than 41% and 80% of analysed fruit juices. The highest concentration of Pb and Cd was observed in orange juice (99 and 9.4 µg/l). Furthermore, incidence of Pb and Cd in 58.9% and 4.9% of fruit juices were higher than the established Codex maximum permissible level. The data showed that total hazard quotients (THQ) for Pb and Cd metals in fruit juices were less than 1 in adults and children, meaning that no major non-carcinogenic risk is resulted from consumption of fruit juice samples. In Cd, the highest calculated CR at the 95th percentile for carcinogenic risk was 1.47 × 10−5 (multi-fruits for children) and 1.43 × 10−5 (orange juice for children) as determined by Monte Carlo simulation model. In addition, for the carcinogenic risk of Pb in adults and children, the safest risk value (≤10−6) was indicated. The calculated CR of Cd and Pb in juices for adults and children was lower than the permissible carcinogenic risk value set by USEPA (1 × 10−5). Based on the results, fruit juices are not the major source of Cd and Pb intake by Iranian consumers.

Synthesis and thermal stability of ferrites added polymers nanocomposites

Nanocomposites of ferrite and polymer constituents with the ordered combination (x) wt% Ni0.48Cu0.12Zn0.4Fe2O4 + (1-x) wt% polyaniline, (0 ≤ x ≤ 1) and (x) wt% (NCZ-PANI), Ni0.48Cu0.12Zn0.4Fe2O4 + (1-x) wt% paraformaldehyde, (0 ≤ x ≤ 1) (NCZ-PFD) were prepared by mechanical alloying method. A microwave digestion system was used to prepare nanopowders of Ni0.48Cu0.12Zn0.4Fe2O4 (NCZ) by microwave hydrothermal method. Infrared Fourier Transform Spectroscopy (FTIR) was used to characterise the samples. Spinel and polymer phases were confirmed by the characterisation tests in the composite samples. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) were used to study the thermal properties of nanocomposites. It reveals that thermal stability is increased with ferrite content for the nanocomposites. The DC conductivity increased with polymer content.

Development of Temperature Calibration Device for Microwave Digestion System in Biochemical Laboratory

As a sample pretreatment device, microwave digestion instrument is widely used in biochemical laboratories. The temperature parameters of the microwave digestion instrument directly decide the accuracy of the experimental results. At present, there is no relevant calibration specification，method or device for microwave digestion system in China. Due to the special working principle of the microwave digestion instrument, the calibration device must be used in the high temperature microwave environment, and the ordinary temperature measuring device will cause ignition, explosion and other phenomena, which will endanger the life and health of the calibration personnel. This article presents a set of calibration device for microwave digestion system, with measuring range of (0~200) °C, accuracy of no less than ± 0.1 °C, and resolution of 0.01 °C. The presented device also solves the potential problems of ignition and explosion, which commonly exist in ordinary temperature measuring devices.

Chemical Analysis and Quality Assessment of Honey Obtained from Different Sources

The purpose of this paper was to evaluate the quality of bee honey from different sources: beekeeper, local market and organic honey. Sensory analysis was performed and the water content, pH, acidity, protein content and total metal content (Cu, Cr, Mn, Co, Ni, Pb, Cd, Fe) were determined. The sensory analysis was carried out by a group of untrained panelists for quality assessment of honey. The metal content was determined by graphite atomic absorption spectrometry (GTAAS). Mineralization was carried out in a microwave digestion system, in a high-pressure polytetrafluoroethylene (PTFE) vessel, using a standard acid-digestion protocol. The results regarding the physico-chemical parameters showed that the honey samples were in accordance with the quality regulations for honey as a commercial product. The concentration of metals in the investigated honey samples varied in the order Cu > Cr > Pb > Fe > Ni > Mn > Co > Cd, the values being within the limits established by the EU Commission (No. 1881/2006). The variations observed in the evaluated parameters can be caused by the difference in plant species from which the honey comes, the harvesting period and the level of environmental pollutants. The Pearson correlations between the physico-chemical parameters and the metals indicate that water content (wc) is strongly negatively correlated with Cd and Ni, while pH is strongly positively correlated with Mn and Fe. Moreover, EC is strongly negatively correlated with Ni and Fe, and the Brix degrees are strongly positively correlated with Cd and Ni. Statistically significant positive correlation was found between Brix–Cd, Ni–Cd and Cu–Cr and a statistically significant negative correlation was detected between wc and Cd.

QUANTIFICATION OF LEAD CONTAMINATION IN DIFFERENT SAUDI CHOCOLATE BRANDS USING ATOMIC ABSORPTION TECHNIQUE

Introduction: Although chocolate and candies are widely preferred snacks for children and adults, they can carry a risk of lead (Pb) contamination. The lead is considered as a toxic heavy metal that can cause many diseases to adults, including renal, reproductive, nervous, immune, and cardiovascular systems diseases. In children, lead can cause behavioral, developmental diseases and learning deficits. Aim and objectives:Our aim in this study is to measure the lead concentrations in different Saudi chocolate brands from different Saudi cities in order to compare it to the American FDA recommended levels of lead.Secondary objective: to assess if chocolate lead contamination contributes to the high blood lead levels that was found in our pediatric population. Methods: Ten different chocolate brands products were brought from different Saudi cities markets these samples were digested using (MARS 6) Microwave Digestion system. The clear digested samples were diluted to 50 ml and subjected for the trace elements determination by Flame atomic absorption spectrometry using AAS-7000. Results:All chocolate products that we investigated have shown lead levels between (0.00006 to 0.00654 ppm) which are below the recommended levels. Conclusion:Depending on our findings, the different chocolate brands that we have studied are within the acceptable ranges of lead contamination, as recommended by the American FDA. Further studies should focus on other causes of lead exposure as we have a high blood lead levels in our pediatric population.

Influence of marine vertebrates on organic matter, phosphorus and other chemical element levels in Antarctic soils

The presence of marine vertebrates in dense reproductive colonies and other aggregations contributes to the input of organic matter and nutrients into the local environment and it is believed that chemical elements are subsequently remobilized from the excreta of these animals. In this study, we investigated the influence of marine vertebrates on trace elements levels (As, Cd, Co, Cu, Fe, Li, Lu, Mg, Mn, Ni, Pb, Sb, Sc, Se, Sm, Sn, Sr, Tb, U and Zn), nutrient (total phosphorus) and soil organic matter (SOM) content from five locations with and without the presence of seabirds and marine mammals in Admiralty Bay, King George Island, South Shetland Islands, Antarctica. Soils were acid digested using a microwave digestion system, elements were quantified using inductively coupled plasma mass spectrometry and SOM was calculated by loss-on-ignition. The non-influenced and vertebrate-influenced soils had similar concentrations of most of the trace elements assessed, however, we observed a significant increase in SOM and P that was positively correlated with the concentrations of As, Cd, Se, Sr and Zn. Although marine vertebrates did not appear to significantly increase the elemental concentrations in the soils examined here, there is a clear evidence of selective enrichment indicating a zoogenic influence. Comparing our results with other studies, we conclude that soil elemental levels are result from an interplay between local geology, vertebrate diet and colony size. Further studies with increased sample size are required to obtain a better understanding of the influence of marine vertebrates on chemical element levels in Antarctic soils.

Levels of selected trace metals in enset (Ensete ventricosum (Welw.), Cheesman) (Unprocessed and processed) and soil of siltie zone, Southern Ethiopia.

Enset (Ensete ventricosum) is an important co staple crop for greater than 20 million people in southern and southwestern Ethiopia. In this study, the concentration of selected trace metals (Pb, Zn, Hg, Cd, Cu, Ni, Co, Fe, Mn, Cr and Pb) in enset pant, its food product and corresponding soil sampled from Siltie zone, Southern Nations, Nationalities, and Peoples Region of Ethiopia were determined. The known weights of oven-dried enset plant and food samples were digested in microwave digestion system whereas acid-wet digestion method was used for soil samples. The digests were subsequently analyzed for heavy metals content by inductively coupled plasma optical emission spectrometry (ICP-OES). The results showed that the relative abundance of trace metals in the enset sample was in the order Fe> >Mn>Zn>Cu>Ni>Pb>Cr≈Cd>Hg>Co and Fe> >Zn>Mn>Ni>Cu>Pb>Cr>Cd>Hg>Co in food samples. The results obtained were within the safe limits set by the FAO/WHO except for Pb (0.48 ± 0.09–3.68 ± 0.57) and Cd (1.04 ± 0.19 mg/kg) in samples from west Azerinet. Also, the result showed the concentrations of metals in the food products were significantly greater than that of enset plant, which shows there may have the potential to be contaminated during food manufacturing steps. The sampled soils were found to be between weakly acidic to weakly basic (pH: 6.15–7.62) and the levels of the trace metals were determined in the acceptable range recommended by FAO/WHO for agricultural soil. Thus, it is important to develop new or improved procedure for processing enset in order to counter attack the potentially toxic trace metals contamination of enset food products that may occur during fermentation process.