[Objectives]This study was conducted to detect the contents of heavy metal lead and chromium in food packaging bags.[Methods]The contents of heavy metal lead and chromium in food packaging bags were determined by micr...[Objectives]This study was conducted to detect the contents of heavy metal lead and chromium in food packaging bags.[Methods]The contents of heavy metal lead and chromium in food packaging bags were determined by microwave digestion-flame atomic absorption spectrophotometer.With concentrated nitric acid and 30%hydrogen peroxide solution as the digestion system,food packaging bags of different materials,plastic packaging bags and paper packaging bags,were ultrasonically digested and then determined for the contents of heavy metal lead and chromium by flame atomic absorption spectrophotometry.[Results]The determination results showed that the linear correlation coefficient of lead was 0.9967,and the linear correlation coefficient of chromium was 0.9977.The method has the characteristics of simplicity,high analysis speed and high sensitivity.[Conclusions]This study provides a theoretical basis for the safety of food packaging bags.展开更多
Two kinds of packaged processes by nickel on the surface of titanium carbide particle are studied in this work. One is the chemical nickel-plating, the other is the organometallic compound decomposition. The compositi...Two kinds of packaged processes by nickel on the surface of titanium carbide particle are studied in this work. One is the chemical nickel-plating, the other is the organometallic compound decomposition. The composition, structure and morphology of the packaged powder were analyzed with XRD, DAT/TGA, SEM, EPMA etc. It has been shown that nickel was even dispersed on the surface of titanium carbide particle by the. two kinds of processes, deposited nickel exists as spherical particles of about 0.1 μm in diameter. The merits and demerits of the two kinds of processes have been compared, the organometallic copmound decomposition among them is a kind of hopeful method, which is not used by other researchers.展开更多
In the present study, the varieties of papers and paperboards (PPBs) used in India for food packaging were qualitatively and quantitatively analyzed for the heavy metal contamination with the help of ICP-OES (Inductiv...In the present study, the varieties of papers and paperboards (PPBs) used in India for food packaging were qualitatively and quantitatively analyzed for the heavy metal contamination with the help of ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometry). Total 10 different types of food packaging PPBs were procured from local market and analyzed for 14 heavy metals (Al, As, B, Ba, Co, Cr, Cu, Fe, Mn, Ni, Pb, Te, Ti and V). Quantities of heavy metals in the samples were compared with permitted values published by the European Council. Heavy metals like Al, As, Ba, Cr, Co, Ni, Pb and V were observed in more than the permitted concentration in some of the samples. Heavy metals toxicity in food packaging material is a serious concern as the edible items get exposed to these metals and also generate volatile odorous compounds which considerably impact the quality of food and affect consumer's health.展开更多
Metallic elements have various origins: natural and anthropogenic sources as geochemical, marine and atmospheric sources resulting from the fallout of pollutants emitted or dust raised and which are transported by wat...Metallic elements have various origins: natural and anthropogenic sources as geochemical, marine and atmospheric sources resulting from the fallout of pollutants emitted or dust raised and which are transported by water and air currents. Thus marine, brackish and fresh continental waters may have high metal concentrations. In addition, some essential metals can become toxic above certain concentration values in aquatic environments. The aquatic ecosystems of Cotonou channel and lake Nokoué receive the pollutants charges from the town cities of Cotonou, Abomey-Calavi and town hall of So Ava. The aim of this study is to analyze waters from Eighteen (18) stations identified in the two ecosystems (nine by ecosystem). The concentrations of magnesium (Mg), calcium (Ca), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), selenium (Se), cadmium (Cd), beryllium (Be), aluminum (Al), strontium (Sr), molybdenum (Mo), silver (Ag), tin (Sn), barium (Ba), platinum (Pt), mercury (Hg), thallium (Tl), lead (Pb), thorium (Th) and uranium (U) were measured after acid digestion of the water samples using the inductively coupled plasma source mass spectrometer (ICP-MS). The results of the analyses indicate an unequal distribution of metals in the different ecosystems. However, atypical concentrations were observed at some stations of the lake and the channel. Magnesium, calcium and manganese have very high values in Lake Nokoué respectively at Ganvié market station GAN_M (2990 ± 105 mg/L), Ganvié center, station GAN_C (4991 ± 177 mg/L) and Lake middle station MLak4 (10662 ± 17.03 μg/L). On the other hand, iron, aluminum and strontium have very high concentrations in the Cotonou Channel respectively at Agbato station AGB (5236 ± 103 and 8289 ± 519 μg/L) and at the estuary station EST (6118 ± 68 μg/L). The concentrations were compared to wells and cborehole waters in sixth neighborhood of Cotonou. We have used statistical analyzers such as MANOVA which have made it possible to classify the waters and metals in the ecosystems studied compared to groundwater and Well water waters. We use hierarchical clustering on principal components to identify similarities between stations based on metal concentration with R software packages “FactoMineR” and “factoextra”. In general, we can conclude that most of the metals have an anthropogenic source except strontium and major elements (Ca and Mg) which could respectively provide from marine waters and geochemical sources.展开更多
基金Supported by Special Scientific Research Project of Shaanxi Provincial Department of Education(16JK1275)。
文摘[Objectives]This study was conducted to detect the contents of heavy metal lead and chromium in food packaging bags.[Methods]The contents of heavy metal lead and chromium in food packaging bags were determined by microwave digestion-flame atomic absorption spectrophotometer.With concentrated nitric acid and 30%hydrogen peroxide solution as the digestion system,food packaging bags of different materials,plastic packaging bags and paper packaging bags,were ultrasonically digested and then determined for the contents of heavy metal lead and chromium by flame atomic absorption spectrophotometry.[Results]The determination results showed that the linear correlation coefficient of lead was 0.9967,and the linear correlation coefficient of chromium was 0.9977.The method has the characteristics of simplicity,high analysis speed and high sensitivity.[Conclusions]This study provides a theoretical basis for the safety of food packaging bags.
文摘Two kinds of packaged processes by nickel on the surface of titanium carbide particle are studied in this work. One is the chemical nickel-plating, the other is the organometallic compound decomposition. The composition, structure and morphology of the packaged powder were analyzed with XRD, DAT/TGA, SEM, EPMA etc. It has been shown that nickel was even dispersed on the surface of titanium carbide particle by the. two kinds of processes, deposited nickel exists as spherical particles of about 0.1 μm in diameter. The merits and demerits of the two kinds of processes have been compared, the organometallic copmound decomposition among them is a kind of hopeful method, which is not used by other researchers.
文摘In the present study, the varieties of papers and paperboards (PPBs) used in India for food packaging were qualitatively and quantitatively analyzed for the heavy metal contamination with the help of ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometry). Total 10 different types of food packaging PPBs were procured from local market and analyzed for 14 heavy metals (Al, As, B, Ba, Co, Cr, Cu, Fe, Mn, Ni, Pb, Te, Ti and V). Quantities of heavy metals in the samples were compared with permitted values published by the European Council. Heavy metals like Al, As, Ba, Cr, Co, Ni, Pb and V were observed in more than the permitted concentration in some of the samples. Heavy metals toxicity in food packaging material is a serious concern as the edible items get exposed to these metals and also generate volatile odorous compounds which considerably impact the quality of food and affect consumer's health.
文摘Metallic elements have various origins: natural and anthropogenic sources as geochemical, marine and atmospheric sources resulting from the fallout of pollutants emitted or dust raised and which are transported by water and air currents. Thus marine, brackish and fresh continental waters may have high metal concentrations. In addition, some essential metals can become toxic above certain concentration values in aquatic environments. The aquatic ecosystems of Cotonou channel and lake Nokoué receive the pollutants charges from the town cities of Cotonou, Abomey-Calavi and town hall of So Ava. The aim of this study is to analyze waters from Eighteen (18) stations identified in the two ecosystems (nine by ecosystem). The concentrations of magnesium (Mg), calcium (Ca), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), selenium (Se), cadmium (Cd), beryllium (Be), aluminum (Al), strontium (Sr), molybdenum (Mo), silver (Ag), tin (Sn), barium (Ba), platinum (Pt), mercury (Hg), thallium (Tl), lead (Pb), thorium (Th) and uranium (U) were measured after acid digestion of the water samples using the inductively coupled plasma source mass spectrometer (ICP-MS). The results of the analyses indicate an unequal distribution of metals in the different ecosystems. However, atypical concentrations were observed at some stations of the lake and the channel. Magnesium, calcium and manganese have very high values in Lake Nokoué respectively at Ganvié market station GAN_M (2990 ± 105 mg/L), Ganvié center, station GAN_C (4991 ± 177 mg/L) and Lake middle station MLak4 (10662 ± 17.03 μg/L). On the other hand, iron, aluminum and strontium have very high concentrations in the Cotonou Channel respectively at Agbato station AGB (5236 ± 103 and 8289 ± 519 μg/L) and at the estuary station EST (6118 ± 68 μg/L). The concentrations were compared to wells and cborehole waters in sixth neighborhood of Cotonou. We have used statistical analyzers such as MANOVA which have made it possible to classify the waters and metals in the ecosystems studied compared to groundwater and Well water waters. We use hierarchical clustering on principal components to identify similarities between stations based on metal concentration with R software packages “FactoMineR” and “factoextra”. In general, we can conclude that most of the metals have an anthropogenic source except strontium and major elements (Ca and Mg) which could respectively provide from marine waters and geochemical sources.
