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Memory effect in firearms that is, the possibility for a weapon to release inorganic particles whose elemental composition depends on its entire shooting history, is responsible for most of the interpretation difficulties encountered in forensic gunshot residue analysis. The presence of residues chemically inconsistent with the last discharged round, the creation of particles having unusual elemental profiles, and the dependence of residue population composition on the collection point are all manifestations of memory effect. The experimental results reported in this paper highlight the ineffectiveness of a wide number of gun cleaning procedures in reducing memory effect. Moreover, the common alternative of discharging batches of rounds having a "new" primer mixture does not fully eliminate the possibility to recover "old" residues at least from the shooter's hands. Two brand new pistols and ammunition having lead-based, leadless and heavy metal free primers were used. Specimens, collected both from the shooters' hands and from cotton targets set nearby the gun muzzle, were analyzed by SEM-EDS and by ICP-OES. After discharging 10's of new ammunitions, the number of old residues ejected from the gun muzzle indeed showed an asymptotic decrease to zero. In spite of this, the number of old residues recovered from the shooter's hands did not follow any predictable trend. These different behaviors suggest that all internal components of a gun, and not just the barrel, play a role in memory effect.

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Selenium (Se) is a trace element that plays a crucial role in metabolism; a lack of selenium reduces the body's resistance and immunity, as well as causes other physiological problems. In this study, we aim to identify favorable conditions for improving organic selenium production. The functional microbe Monascus purpureus, which is widely used in food production, was employed to optimize selenium-enriched culture conditions, and its growth mode and selenium-enriched features were investigated. Spectrophotometry, inductively coupled plasma optical emission spectrometry (ICP-OES), and HPLC (High-Performance Liquid Chromatography) were used to determine the effects of various doses of sodium selenite on the selenium content, growth, and metabolism of M. purpureus, as well as the conversion rate of organic selenium. The best culture parameters for selenium-rich M. purpureus included 7.5 mg/100 mL of selenium content in the culture medium, a pH value of 6.8, a culture temperature of 30 °C, and a rotation speed of 180 rpm. Under ideal circumstances, the mycelia had a maximum selenium concentration of approximately 239.17 mg/kg, with organic selenium accounting for 93.45%, monacoline K production reaching 70.264 mg/L, and a secondary utilization rate of external selenium of 22.99%. This study revealed a novel biological route-selenium-rich M. purpureus fermentation-for converting inorganic selenium into organic selenium.

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Contamination of toxins in chicken's liver is a serious concern for human health owing to related threats of cytotoxicity and general pathologies after their digestion. The quantitative investigations were accomplished by calibration curves plotted for all the detected toxins via typical samples arranged in the known concentrations in the chicken liver's matrix. The chicken liver samples were collected from the Khyber Pakhtunkhwa province of Pakistan and found to contain heavy metals like Cu, Mn, Ni, Pb, and Zn. The analytical estimations were performed under the suppositions of local thermodynamic equilibrium (LTE) in terms of optical thin plasma. The maximum concentrations (parts per million) of Cu, Mn, Ni, Pb, and Zn were as 2.87 ± 0.02 ppm, 7.80 ± 0.13 ppm, 2.84 ± 0.02 ppm, 4.00 ± 0.08, and 83.5 ± 2.10 ppm respectively. Abundance of Cu, and Pb was found considerably beyond the maximum accepted boundary of WHO. Likewise, the level of Ni exceeded the permitted bounds of WHO in samples 01 and 02. To validate our laser-induced breakdown spectroscopy investigation, we approximated the abundance of identical (duplicate) chicken livers through digesting the specimens in suitable solvents by a typical technique such as inductively coupled plasma/optical emission spectrometry (ICP/OES) and the results acquired were in outstanding harmony. Furthermore, the existence of detected toxins was also checked using energy dispersive X-ray spectroscopy (EDX). It is worth stating that larger amounts of Cu, Ni, and Pb in poultry may cause a severe hazard to customers which required security actions and precautions. Our findings are extremely important to make an awareness among the people due to associated health hazards after the digestion of toxins through chicken liver and to protect numerous human lives.

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In recirculating aquaculture system (RAS), ammonium excreted by the fish is typically transformed to less toxic nitrate by microbial activity in bioreactors. However, nitrate-nitrogen load can be harmful for the receiving water body when released from the RAS facility. A new type of water treatment system for a RAS was designed, including a passive woodchip denitrification followed by a sand filtration introduced into a side-loop of an experimental RAS, rearing rainbow trout (Oncorhynchus mykiss). In the process, woodchips acted as a carbon source for the denitrification, aiming at a simultaneous nitrogen removal and reduction of water consumption while sand filtration was used to remove organic matter and recondition the circulating water. A variety of chemical analyses and toxicological tests were performed to study the suitability of the process and to ensure the absence of harmful or toxic substances in the system. The results did not show increased toxicity, and no increased mortality was reported for the raised species. After the start-up of the system, the concentrations of fatty acids (e.g., hexadecanoic acid

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In this research, effect of soaking time, acidity and temperature on the removal of lead and cadmium from rice was investigated. Different rice treatments were involved i.e. three soaking times (0, 15, and 30 min), three temperatures (20, 25, and 30 °C) and four concentrations of glacial acetic acid (0.5%, 1%, 2%, and 3%). Results showed that few samples have shown lead concentrations above the maximum limit set by the World Health Organization (WHO) and the UN Food and Agriculture Organization (FAO) of 0.2 mg/kg, whereas, all cadmium concentrations were below the limit of 0.4 mg/kg. A decrease in lead and cadmium concentrations were observed with increasing time of soaking. Lead had the lowest concentration at 20 °C, while cadmium had the lowest concentration at 30 °C. Cadmium concentration decreased with increasing water acidity, while the lead concentration reached the lowest concentration with 1% acidity.

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Objective: To establish the method for determination of tungsten and insoluble compounds in the air of workplace by inductively coupled plasma optical emission spectrometry (ICP-OES) . Methods: The tungsten and insoluble compounds were digested by microwave digestion apparatus using nitric acid and hydrofluoric acid, detected by ICP-OES. Results: The linearity of tungsten and insoluble compounds (as tungsten) were good at the range of 0.16-100.0 µg/ml, the minimum quantitation concentration was 0.11 mg/m(3), the recovery was ranged from 81.9%-97.1%, the RSD of intra-and inter-batch precision were 0.5%-2.5% and 1.2%-4.4%, respectively. Conclusion: The determination method meet the requirement of analysis and apply to the determination of tungsten and insoluble compounds in the air of workplace.

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Asfaka, fir, flower, forest flowers and orange blossom honeys harvested in the wider area of Hellas by professional beekeepers, were subjected to mineral content analysis using inductively coupled plasma optical emission spectrometry (ICP-OES). The main purpose of this study was to characterize the mineral profile and content of toxic metals such as lead, cadmium and chromium, and investigate whether specific minerals could assist accurately in the botanical origin discrimination with implementation of chemometrics. Twenty-five minerals were identified (Ag, Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Mo, Ni, Pb, Sb, Se, Si, Ti, Tl, V, Zn) and quantified. Results showed that the mineral content varied significantly (p < 0.05) according to honey botanical origin, whereas lead, cadmium, and chromium contents ranged between 0.05-0.33 mg kg-1, <0.05 mg kg-1, and in the range of <0.12 to 0.39 mg kg-1, respectively. Fir honeys from Aitoloakarnania region showed the highest mineral content (182.13 ± 71.34 mg kg-1), while flower honeys from Samos Island recorded the highest silicon content (16.08 ± 2.94 mg kg-1). Implementation of multivariate analysis of variance (MANOVA), factor analysis (FA), linear discriminant analysis (LDA), and stepwise discriminant analysis (SDA) led to the perfect classification (100%) of these honeys according to botanical origin with the use of Al, As, Ca, Mg, Mn, Ni, Pb, Sb, Si, Zn and total mineral content. However, the higher lead content in the majority of samples than the regulated upper limit (0.10 mg kg-1), sets the need for further improvements of the beekeepers' practices/strategies for honey production.

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The rice grain endosperm is mostly composed of starch , which serves as the major source of calories for more than half of the world's population. Macro and micronutrients make a minor proportion of the rice grain, which particularly gets accumulated in outer aleurone layer, which are in general eliminated upon milling. Because rice is the major staple, it is seen as an efficient mechanism for delivering both macro- and micronutrients, particularly for the poor who do not have ample access to diversified diets. Enriching micronutrient and macronutrient concentrations in milled rice of endosperm and/or in brown rice, is an important dietary intervention to create health benefits of rice consumers. Efforts are underway to increase the nutritional content of rice through bio/fortification approaches. The plant takes up these same elements from the soil, redirect the transport of these elements into the grain. Thus besides biofortification strategies, scientists can also use the knowledge to design proper soil nutrient management to enrich micronutrients in the grains. Therefore, it is important to be able to determine the macro- and the micronutrient composition of the vegetative parts of the rice plant and of the rice grain. In this chapter, nitric-perchloric acid digestion and inductively coupled plasma-optical emission spectrometry (ICP-OES) methods routinely used in IRRI's Grain Quality and Nutrition Services Laboratory (GQNSL) to determine the concentrations of various macro- and micronutrients found in the rice grain and the rice plant, are described.

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BACKGROUND: Citrus fruits are widely consumed around the world. Several elements are known to have important physiological functions in living things, whereas others are reported to have toxic effects. This study was aimed to analyze the concentration of macro, micro and trace elements in citrus fruit varieties. Samples were acid digested using a microwave system and analyzed for macro elements by inductively coupled plasma-optical emission spectrometry (ICP-OES) and for micro and trace elements by inductively coupled plasma-mass spectrometry (ICP-MS). The application of analytical techniques was analyzed by determining method validation parameters including limits of detection and quantification, linearity, precision, spiking experiments and analyzing certified reference material (NIST CRM-1570a), Spinach leaves. RESULTS: The elemental levels of citrus fruits were found largely to be dependent upon the type of analyzed samples. Among nutritionally important elements, citrus fruits were good sources of potassium (95.13-270.4 mg kg-1 ), calcium (10.57-75.29 mg kg-1 ), zinc (466.5-1611 µg kg-1 ) and manganese (35.35-1902 µg kg-1 ). The concentrations of toxic elements (Pb, Cd, As, Al, Hg) were very low. CONCLUSION: In general, the concentrations of analyzed elements were within the critical levels specified by the Food and Agriculture Organization/World Health Organization and Food and Nutrition Board USA. Linear discriminant analysis successfully separated the samples into clear groups with 93.9% correct classification. © 2018 Society of Chemical Industry.

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Objective@#To establish the method for determination of tungsten and insoluble compounds in the air of workplace by inductively coupled plasma optical emission spectrometry (ICP-OES) .@*Methods@#The tungsten and insoluble compounds were digested by microwave digestion apparatus using nitric acid and hydrofluoric acid, detected by ICP-OES.@*Results@#The linearity of tungsten and insoluble compounds (as tungsten) were good at the range of 0.16-100.0 μg/ml, the minimum quantitation concentration was 0.11 mg/m3, the recovery was ranged from 81.9%-97.1%, the RSD of intra-and inter-batch precision were 0.5%-2.5% and 1.2%-4.4%, respectively.@*Conclusion@#The determination method meet the requirement of analysis and apply to the determination of tungsten and insoluble compounds in the air of workplace.

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Objective: To establish the method for determination of barium sulfate in the air of workplace. Methods: The barium sulfate was collected by dichloride ethylene filter membrane and then processed by alkali fusion method. Inductively coupled plasma optical emission spectrometry (ICP-OES) was used for the detection of barium sulfate. Results: The sampling efficiency was 100%, the linearity of ICP-OES was good at the range of 0.1~100.0 µg/mL, the recovery was ranged from 93.0%~97.8%, the RSD of intra- and inter-batch precision were 3.7%~7.6% and 4.7%~8.8%, respectively. Conclusion: The sampling method and determination method meet the requirements of analysis and apply to the collection and determination of barium sulfate in the air of workplace.

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A simple method of simultaneous determination of aluminum (Al), barium (Ba), calcium (Ca), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), nickel (Ni), strontium (Sr) and zinc (Zn) in brews of ground and soluble coffees was proposed. It relied on acidification of brews with HNO3 to 1.3 mol L-1 and their analysis by inductively coupled plasma optical emission spectrometry. Precision of 0.1-9% and detection limits from 0.07 ng mL-1 (Sr) to 3 ng mL-1 (Ni) were achieved. Trueness of the method was verified by comparison of results with those achieved with wet digestion and by the recovery study, and was better than 5%. Additionally, chemical fractionation by tandem solid phase extraction with reverse-phase and strong cation-exchange extraction tubes was carried out. Differences in chemical fractionation patterns, particularly the residual fraction, was useful for differentiation of ground and soluble coffees by analysis of variance, principle component analysis and hierarchical clustering analysis.

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Objective@#To establish the method for determination of barium sulfate in the air of workplace. @*Methods@#The barium sulfate was collected by dichloride ethylene filter membrane and then processed by alkali fusion method. Inductively coupled plasma optical emission spectrometry (ICP-OES) was used for the detection of barium sulfate. @*Results@#The sampling efficiency was 100%, the linearity of ICP-OES was good at the range of 0.1~100.0 μg/mL, the recovery was ranged from 93.0%~97.8%, the RSD of intra- and inter-batch precision were 3.7%~7.6% and 4.7%~8.8%, respectively. @*Conclusion@#The sampling method and determination method meet the requirements of analysis and apply to the collection and determination of barium sulfate in the air of workplace.

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The concentration levels of 20 metals were analyzed by ICP-OES in edible seaweed (Chondrus, Eisenia, Gelidium, Himanthalia, Laminaria, Palmaria, Porphyra, Undaria), from two origins (Asia vs EU) according to their cultivation practices (conventional vs organic). Red seaweed showed higher concentrations of trace and toxic elements. Porphyra may be used as a potential bioindicator for metals. Significant differences were found between the Asian vs European mean contents. The mean Cd level from the conventional cultivation (0.28 mg/kg) was two points higher than the organic cultivation (0.13 mg/kg). A daily consumption of seaweed (4 g/day) contributes to the dietary intake of metals, mainly Mg and Cr. The average intakes of Al, Cd and Pb were 0.064, 0.001 and 0.0003 mg/day, respectively. Based on obtained results, this study suggests that exposure to the toxic metals analyzed (Al, Cd and Pb) through seaweed consumption does not raise serious health concerns, but other toxic metals should be monitored.

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Objective To establish a method for the determination of 8 heavy metal elements of Pb,Cd,As,Hg,Co,V,Se,Mo in iron dextran by inductively coupled plasma optical emission spectrometry (ICP-OES).Method Through selection of detection wavelengths,optimization of instrument parameters,verification of matrix effect interference and investigation of internal standard for correction of matrix effect interference,the 8 heavy metal elements were analyzed by ICP-OES.Results The recovery rate of the detected elements were increased from 83％-90％ to 94％-100％,after correction of matrix effect interference by internal standard method.The accuracy of the method were good.The spiked recoveries of the detected elements were from 94.3％ to 101.5％.The precision of the method were good (RSD ＜ 3.5％,n =6).The linearities of the detected elements were good,and the correlation coefficients were all greater than 0.999.The detection limits were from 0.22 to 8.54 ng/mL.The quantization limits were from 0.68 to 25.73 ng/mL.Conclusion The established method was accurate,sensitivity,rapid and reliable,which can be applied to the determination of contents of 8 heavy metal elements in iron dextran.

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Objective To establish a method for the determination of 8 heavy metal elements of Pb,Cd,As,Hg,Co,V,Se,Mo in iron dextran by inductively coupled plasma optical emission spectrometry (ICP-OES).Method Through selection of detection wavelengths,optimization of instrument parameters,verification of matrix effect interference and investigation of internal standard for correction of matrix effect interference,the 8 heavy metal elements were analyzed by ICP-OES.Results The recovery rate of the detected elements were increased from 83％-90％ to 94％-100％,after correction of matrix effect interference by internal standard method.The accuracy of the method were good.The spiked recoveries of the detected elements were from 94.3％ to 101.5％.The precision of the method were good (RSD ＜ 3.5％,n =6).The linearities of the detected elements were good,and the correlation coefficients were all greater than 0.999.The detection limits were from 0.22 to 8.54 ng/mL.The quantization limits were from 0.68 to 25.73 ng/mL.Conclusion The established method was accurate,sensitivity,rapid and reliable,which can be applied to the determination of contents of 8 heavy metal elements in iron dextran.

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Objective To establish a method for the determination of eight heavy metal elements ofPb,Cd,As,Hg,Co,V,Se,Mo in iron dextran by inductively coupled plasma optical emission spectrometry (ICP-OES).Method Through selection of detection wavelengths,optimization of instrument parameters,correction of spectral interference,verification of ionization interference and investigation of suppression methods,the eight heavy metal elements were analyzed by ICP-OES.Results The recovery rate of the detected elements increased 5％ to 10％ by suppression of ionization interference.The accuracy of the method was good.The spiked recovery rates of the detected elements were from 95.7％ to 101.1％.The precision of the method were good (RSD ＜ 3.6％,n =6).The linearities of the detected elements were good,and the correlation coefficients were all greater than 0.999.The detection limits were from 0.15 to 8.09 ng/mL.The quantization limits were from 0.46 to 24.26 ng/mL.Conclusion The method was accurate,sensitivity,rapid and reliable,which can be applied to the determination of contents of eight heavy metal elements in iron dextran.

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A new ionic liquid loaded silica gel amine (SG-APTMS-N,N-EPANTf2) was developed, as an adsorptive material, for selective adsorption and determination of zirconium, Zr(IV), without the need for a chelating intermediate. Based on a selectivity study, the SG-APTMS-N,N-EPANTf2 phase showed a perfect selectivity towards Zr(IV) at pH 4 as compared to other metallic ions, including gold [Au(III)], copper [Cu(II)], cobalt [Co(II)], chromium [Cr(III)], lead [Pb(II)], selenium [Se(IV)] and mercury [Hg(II)] ions. The influence of pH, Zr(IV) concentration, contact time and interfering ions on SG-APTMS-N,N-EPANTf2 uptake for Zr(IV) was evaluated. The presence of incorporated donor atoms in newly synthesized SG-APTMS-N,N-EPANTf2 phase played a significant role in enhancing its uptake capacity of Zr(IV) by 78.64% in contrast to silica gel (activated). The equilibrium and kinetic information of Zr(IV) adsorption onto SG-APTMS-N,N-EPANTf2 were best expressed by Langmuir and pseudo second-order kinetic models, respectively. General co-existing cations did not interfere with the extraction and detection of Zr(IV). Finally, the analytical efficiency of the newly developed method was also confirmed by implementing it for the determination of Zr(IV) in several water samples.

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AIM: The aim of this study was to evaluate the release of nickel and chromium ions in human saliva during fixed orthodontic therapy. MATERIALS AND METHODS: Ten patients with Angle's Class-I malocclusion with bimaxillary protrusion without any metal restorations or crowns and with all the permanent teeth were selected. Five male patients and five female patients in the age group range of 14 to 23 years were scheduled for orthodontic treatment with first premolar extraction. Saliva samples were collected in three stages: sample 1, before orthodontic treatment; sample 2, after 10 days of bonding sample; and sample 3, after 1 month of bonding. The samples were analyzed for the following metals nickel and chromium using inductively coupled plasma optical emission spectrometry (ICP-OES). RESULTS: The levels of nickel and chromium were statistically significant, while nickel showed a gradual increase in the first 10 days and a decline thereafter. Chromium showed a gradual increase and was statistically significant on the 30th day. CONCLUSION: There was greatest release of ions during the first 10 days and a gradual decline thereafter. Control group had traces of nickel and chromium. While comparing levels of nickel in saliva, there was a significant rise from baseline to 10th and 30th-day sample, which was statistically significant. While comparing 10th day to that of 30th day, there was no statistical significance. The levels of chromium ion in the saliva were more in 30th day, and when comparing 10th-day sample with 30th day, there was statistical significance. CLINICAL SIGNIFICANCE: Nickel and chromium levels were well within the permissible levels. However, some hypersensitive individuals may be allergic to this minimal permissible level.

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This study aimed to determine the heavy metals (lead, cadmium, and chromium) concentration in lipsticks of different price categories sold in the Malaysian market and evaluate the potential health risks due to daily ingestion of heavy metals in lipsticks. A total of 374 questionnaires were distributed to the female staff in a public university in Malaysia in order to obtain information such as brand and price of the lipsticks, body weight, and frequency and duration of wearing lipstick. This information was important for the calculation of hazard quotient (HQ) in health risk assessment. The samples were extracted using a microwave digester and analyzed using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The concentrations of lead, cadmium, and chromium in lipsticks ranged from 0.77 to 15.44 mg kg(-1), 0.06-0.33 mg kg(-1), and 0.48-2.50 mg kg(-1), respectively. There was a significant difference of lead content in the lipsticks of different price categories. There was no significant non-carcinogenic health risk due to the exposure of these heavy metals through lipstick consumption for the prolonged exposure of 35 years (HQ < 1).

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