Air-acetylene Flame Research Articles

Content of The Heavy Metal Cd in Tilapia Fish from Rawa Taliwang Lake

The heavy metal Cadmium (Cd) can accumulate in the fish's body. The aim of this research is: To determine the metal content of Cadmium (Cd) in Tilapia fish (Oreochromis niloticus) originating from Lake Rawa Taliwang. The specific benefit is to protect consumers who consume Tilapia from heavy metal contamination. The research was carried out at Rawa Taliwang Lake, namely in an area that was submerged in water. Two stations were chosen for this research, namely in the eastern and western parts of the lake. Method of data collection was carried out using gill nets. Two fish were taken at each station. Next, the tilapia fish samples are put into a plastic bag and then stored in a sample box. The research samples were then analyzed at the Mataram University analytical laboratory and at the Environmental and forestry services West Nusa Tenggara (DLHK NTB) Environmental Laboratory. The data analysis method was carried out by taking tilapia ikab muscle tissue and then analyzing the heavy metal content in the form of Cadmium (Cd) using an Atomic Absorption Spectrophotometer. Measurement of heavy metals in tilapia fish tissue was carried out by adding concentrated HNO3 and HClO4, heating at a temperature of 60-70ºC for 2-3 hours until the solution was clear. Samples are ready to be measured with AAS using an air-acetylene flame. The conclusion of this research is that the content of the heavy metal Cd in Tilapia fish (Oreochromis niloticus) originating from Lake Rawa Taliwang ranges from 0.19 – 2,18 mg/kg (ppm), exceeds the permitted quality standard, namely 0.3 mg/kg.

Analysis of The Heavy Metal Cd Content in Ricefield Eel from Rawa Taliwang Lake, West Sumbawa Regency

It is important to carry out research on heavy metal in fish body. The specific aims and targets of this research are: Want to know the metal content of Cadmium (Cd) in Ricefield eels (Monopterus albus) which comes from Rawa Taliwang Lake. The specific benefit is to protect consumers who consume fish from heavy metal contamination. The research was carried out at Rawa Taliwang Lake, namely in an area that is submerged in water. There are 2 research stations, namely in the eastern and western parts of the lake. Data collection method was carried out using traps (Bubu). Four Ricefield eel samples were taken at each station. Next, the rice eel samples were put into a plastic bag and then stored in a sample box. The research samples were then analyzed at the Mataram Uviversity analytical laboratory and at Environmental Laboratory of the Environmental and forestry services West Nusa Tenggara Province. The data analysis method is carried out by taking the tissues from the Ricefield eel muscles, and then analyzed for Cd heavy metal content by using Atomic Absorption Spectrophotometer. Measurement of heavy metals in Ricefield eel tissue was carried out by adding concentrated HNO3 and HClO4 , heated at a temperature of 60-70ºC for 2-3 hours until the solution was clear. Samples are ready to be measured with AAS using an air-acetylene flame. The conclusion of this research is that the content of Cd heavy metal in Ricefield Eels (Monopterus albus) originating from Rawa Taliwang Lake ranges from 2.55 - 4.01 mg/kg (ppm).

Serpentine environment prevails over geographic distribution in shaping the genetic diversity of Medicago lupulina L.

Edaphic conditions of serpentine soils, naturally rich in heavy metals, act as a strong selection pressure that shapes specific metal-tolerant ecotypes. Medicago lupulina L. (black medick) is not only a widespread plant species that prefers calcareous and dry soil types but also grows at the borders of serpentine formations. It can also be found in waste and disturbed habitats. This is a species with reported phytoremediation potential, however, there is no published data regarding the impact of the environment on the genetic distribution of this species. The aim of our research was to explore how selection pressure of serpentine soils affects genetic diversity of M. lupulina and to test heavy-metal accumulation capacity of this species. Specimens of 11M. lupulina populations were collected from serpentine outcrops located in Central and Eastern Bosnia as well as from non-serpentine sites. Soil and plant samples were analyzed for the total contents of heavy metals using air-acetylene flame atomic absorption spectroscopy. Genetic diversity was analyzed using AFLP (Amplified Fragment Length Polymorphism) markers. Serpentine soils showed high nickel, cobalt, chromium and iron concentrations. Nickel and manganese concentrations in soil samples and plant material showed statistically significant correlation. Although plants in two populations show the ability to extract Ni, M. lupulina does not show hyperaccumulating properties. Despite severe selective pressure, genetic diversity in serpentine populations is not reduced. Analyses of intrapopulation and interpopulation genetic diversity showed significant genetic differentiation among populations which is not related to their geographic distance. Population from non-metalliferous soil showed clear separation from all other populations. Diversity data suggest that serpentine populations maintain genetic diversity by undetected mechanisms and that edaphic factors rather than geography influence genetic structure analyzed M. lupulina populations.

Human health risk assessment model associated with PM2.5 bound metals in paradip port township, India

This study aimed to assess the environmental risk and human health risks associated with PM2.5-bound metals in Paradip city between January 2019 and December 2021. The seasonal average concentrations of PM2.5 were measured 91.43 ± 70.18 μg m−3, 103.40 ± 60.80 μg m−3, 124.74 ± 62.37 μg m−3, and 159.37 ± 77.88 μg m−3 in pre-monsoon, monsoon, post-monsoon, and winter season respectively. The highest and lowest concentrations are estimated in the winter and pre-monsoon season. Paradip city experienced tropical weather conditions with a hot and humid climate. The wind pattern shows that the predominant wind direction was observed from the south-south-west (SSW) direction. The metals in PM2.5 were analysed using an atomic absorption spectrophotometer (AAS) by air-acetylene flame using a hollow cathode lamp. The average metal concentration decreased in the order of Fe > Al > Zn > Pb > Cr > Mn > Ni > Cu > Co > Cd > As. The value of the geo-accumulation index (Igeo) was evaluated >1 for Cd, Fe, and Zn elements. The health risk assessment (HRA) results showed that non-carcinogenic risk (NCR) was higher through the inhalation route followed by ingestion and dermal contact. The cumulative NCR, which is expressed in terms of the hazard index (HI), is greater than 1 for infant (2.78E+00), child (2.53E+00), and adult (1.04E+00) via inhalation pathway. The total carcinogenic risk (TCR) for infants, children, and adults was estimated at 1.45E-04, 7.24E-05 and 1.25E-05, respectively, which exceeded the acceptable limit of 1.00E-06. Our comprehensive research plays an important role in both policymakers and relevant stakeholders for the preparation of city action plans concerning ambient air pollution, which can improve the air quality in and around Paradip city, India.

Mercury Content in Impacted Wisdom Teeth from Patients of the Legnica-Głogów Copper Area-An In Vitro Pilot Study.

The aim of this study was to determine the content of mercury in impacted third molars from Legnica-Głogów Copper Area residents to emphasize the effects of environmental pollution on the human body. A group of 72 patients with an average age of 27.3 ± 6.9 years participated in the study. Within this study, the research group (Legnica-Głogów Copper Area residents) comprised 51 individuals, while the control group (residents of Wrocław) consisted of 21 participants. A higher number of female individuals participated in the research (55). The amount of mercury present in the samples was determined through atomic absorption spectrometry with the use of a SpectraAA atomic absorption spectrometer and a V2 AA240FS flame attachment that utilized an air-acetylene flame. The accumulation of Hg in the teeth of members of the control group residing in Wrocław was studied, with a focus on identifying the risk factors that contribute to this phenomenon. The final model analyzed the presence of various factors, including thyroid and parathyroid gland diseases, cardiac diseases, and interval-scale Vit. D3 concentration. Among these factors, the presence of cardiac diseases was deemed statistically significant in relation to an increase in Hg concentration in third molars (rate ratio = 2.27, p < 0.0001). The concentration of mercury increased with the age and time of residence in the L-G Copper District.

Strontium monofluoride – a new molecule to measure fluorine using high-resolution continuum source flame molecular absorption spectrometry and its application for gasoline analysis

In this work, for the first time, strontium monofluoride was generated in an air-acetylene flame of a high-resolution continuum source molecular absorption spectrometer with the aim of fluorine determination via molecular absorption. The particular task was the determination of organic fluorine in gasoline/its components dissolved in xylene. Sequential measurements in the area of the most intensive absorption of the molecule were executed to select the spectral range for analysis. The acquired spectra differed from the ones from the literature, especially the emission spectra. The best and comparable sensitivity has been registered near 651 nm and 663 nm in measurements of rotations from the range of the X2Σ+ → A2Π electronic transition of the SrF molecule. Unfortunately, SrOH molecules were also spontaneously formed and absorbed radiation in the selected area. No other spectral interferences were found, except absorption by the SrBr molecule, which could have been formed in the flame despite a relatively low energy bond of 330 kJ/mol. The dependence of generation of the SrF and the SrOH molecules on the flame conditions was studied for pure solvent (xylene) and solutions of investigated samples of gasoline type. The effect of the SrOH molecule was overcome by blank subtraction or the least square background correction. The last method had to be used to overcome the SrBr effect. Due to the various combustion properties of various hydrocarbons and their different behaviour in flame, applying the simplified standard addition method became indispensable. As a source of strontium, an oil Sr standards or Sr acetylacetonate (SrAA) were investigated. The crucial benefit of SrF molecule application was the relatively good solubility (and relatively low price) of SrAA. Under the selected conditions, the characteristic concentration of fluorine was 1.9 and 2.0 mg/L, while the instrumental detection limit was 0.5 and 0.8 mg/L for the 651 and 663 nm ranges, respectively. The analytical technique enables the analysis of samples diluted to a small degree, e.g. 1:3 v:v and the best method detection limit is 1.3 mg/L. The proposed method is fast and cheap.

Analysis of Mercury (Hg) Heavy Metal Content in Rice Snail (Pila ampullacea) Derived from Rawa Taliwang Lake, West Sumbawa Regency

Danu Rawa Taliwang is a large body of water that receives sources of heavy metal pollution from human activities such as agriculture and mining. By using bioindicators such as fish, heavy metals have been detected in the waters. The aim of the study was to determine the content of heavy metal mercury (Hg) in the Rice Field Snail (Pila ampullacea) originating from Lake Rawa Taliwang to enrich Ecotoxicology course material. The special benefit is to protect consumers who consume fish from heavy metal contaminants. Sample Snail was put into a plastic bag and then stored in a sample box. The research sample was then analyzed at the Environmental Laboratory Center for the West Nusa Tenggara Environment and Forestry Office. The method of data analysis was carried out by taking muscle tissue from snails and then analyzing the content of heavy metals in the form of Hg using an Atomic Absorption Spectrophotometer. Heavy metals in snail tissue were measured after adding concentrated HNO3 and HClO4, which were heated at 60-70ºC for 2-3 hours until the solution was clear. Ready samples were measured by AAS using an air-acetylene flame. The conclusion of this study is that the heavy metal content of Hg in rice field snails (Pila ampullacea) originating from Lake Rawa Taliwang to enrich Ecotoxicology course material ranges from 0.96 ppm to 1.91 ppm.

Demonstration of Acetylene–Air Flame by Hydrolysis of Calcium Carbide to Rid Blind Beliefs and Misconceptions Regarding Purported Water Lit Lamp

Demonstration of Acetylene–Air Flame by Hydrolysis of Calcium Carbide to Rid Blind Beliefs and Misconceptions Regarding Purported Water Lit Lamp

An In-Vitro Evaluation of Toxic Metals Concentration in the Third Molars from Residents of the Legnica-Głogów Copper Area and Risk Factors Determining the Accumulation of Those Metals: A Pilot Study

The purpose of this study was to determine tissue concentration of toxic metals, namely Mn, Cr, Ni, Cu, Fe, Cd, Pb, and Zn, in the removed third molars in patients from the Legnica-Głogów copper district. A group of 69 patients with an average age of 27.3 ± 6.9 years was enrolled into the study. There were 16 (23.2%) men and 53 (76.8%) women. Patients were divided into two groups according to the place of residence—residents of the Legnica-Głogów Copper Area (n = 49) and the control group, residents of Wrocław (n = 20). Determination of the Pb, Cd, Cr, Ni, Fe, Mn, Cu, Zn content was performed by atomic absorption spectrometry in an air–acetylene flame using the SpectraAA atomic absorption spectrometer with a V2 AA240FS flame attachment. The content of Fe and Pb in the third molars was higher among residents of the Legnica-Głogów Copper Area (p = 0.016 and p = 0.002, respectively). The significant risk factors that may contribute to the accumulation of toxic metals in teeth were identified. We showed a significant correlation between the level of Cr, Cu, and Zn and age, and between chromium and vitamin D3 concentration in the blood (p &lt; 0.05 for all).

Analysis of Calcium, Potassium, Iron Levels Due to Variations in Soaking Time for Nuts Almond Milk Production using Atomic Absorption Spectrophotometry

Background: Calcium, potassium and iron can be obtained from milk, nuts, eggs, fish, fruit vegetables, green vegetables and products needed by the human body which play a role in maintaining body functions, including cells, tissues, organs and overall function. Objective: Research to determine the levels of these minerals in almond milk using atomic absorption spectrophotometry (AAS). Method: Almonds were soaked for 4, 8, and 12 hours respectively for almond milk 1, 2, and 3 (SA1, SA2, and SA3) and Almendrola packaged milk (SA4). Samples were wet digested with concentrated HNO3. Analysis of calcium, potassium and iron levels using AAS with an air-acetylene flame was 422.7; 766.5; and 248.3 nm for calcium, potassium and iron respectively. Validated methods include accuracy, precision, LOD and LOQ. Results: Results of determining the mineral content of almond milk (mg/100g) for calcium, potassium and iron respectively (2.6551 ± 0.0925; 5.5464 ± 0.3178; 5.8866 ± 0.03805; and 4.5842 ± 0.2590), (2.4096 ± 0.0551; 2.5150 ± 0.0115; 2.6551 ± 0.0557; and 2.5150 ± 0.0551), and (0.3202 ± 0.0282; 0.3307 ± 0.0048; 0.3344 ± 0.011; and 0.3183 ± 0.0045). Conclusion: Validation of the method meets the requirements, soaking impacts increasing mineral levels in Almond Milk, and there are significant differences in calcium, potassium and iron levels in the milk.

Heavy Metals in Honey Collected from Contaminated Locations: A Case of Lithuania

Honey, as a bioindicator, can be used to determine the level of pollution in the environment with selected pollutants, including heavy metals. Twelve locations were selected for experimental studies near the main sources of pollution: industrial sites, landfills, railways, and highways. The honey samples were burned to ash, and the heavy metals in ashes were determined using aqua regia digestion in the microwave digestion system. The concentration of heavy metals (Cd, Cr, Cu, Pb, and Ni) was determined using a Buck Scientific model 210 VGP atomic absorption spectrophotometer with a graphite furnace atomizer and an acetylene-air flame. These median amounts of heavy metals were found in the analyzed honey samples: 0.0030 mg/kg for Cd, 0.0179 mg/kg for Pb, 0.0317 mg/kg for Cr, 0.0999 mg/kg for Cu, and 0.0332 mg/kg for Ni. The obtained results were compared with honey samples research conducted in other countries. It is difficult to compare the level of heavy metal results found in honey from different countries, as the type of honey, soil composition, rainfall, air temperature, the plants from which it was harvested, its vegetation and flowering duration, and the degree of anthropogenic pollution in the area differ. The heavy metal content tested in honey was found to be low, except for the Pb content in one sample of honey, and did not pose a risk to human health. A statistical analysis including average, median, standard deviation, confidence intervals, and Spearman coefficients was performed for the evaluation of the relationships between the heavy metal quantities and the determination of the impact of pollution sources (transport and industry). The correlation analysis showed a strong negative correlation coefficient between heavy metals and distance (r = −0.593 to −0.204).

Pollution and risk assessment of heavy metals in water, sediment and fish (Clarias gariepinus) in a fish farm cluster in Niger Delta region, Nigeria.

The study determined the following heavy metals: cadmium (Cd), chromium (Cr), copper (Cu), manganese (Mn), lead (Pb) and zinc (Zn) concentrations in surface water and in fish pond (water, sediments and farmed fish (Clarias gariepinus)) from a fish farm cluster with the view of assessing its pollution level and associated human health exposure risk to these heavy metals through fish consumption. Samples were digested with aqua regia and metal concentrations were determined with an atomic absorption spectrophotometer equipped with an air acetylene flame. Mean concentrations of the heavy metals (ppm) in surface and pond water ranged as follows: cadmium (below detection limit (bdl): 0.298); chromium (bdl: 0.257); copper (bdl: 0.067); manganese (bdl: 0.163); lead (bdl: 0.736) and zinc (bdl: 0.078) while in sediment, the ranges (mg/kg dry weight) were as follows: cadmium (1.156-3.329); chromium (9.439-14.373); copper (26.710-121.819); manganese (3.143-37.202); lead (0.340-1.537) and zinc (87.681-371.060). The mean concentrations of the metals in surface water were significantly different (p < 0.05) from those in sediment in all the sampling sites. The mean metal concentrations (mg/kg dry weight) in C. gariepnus were in the following ranges: cadmium (0.733-1.405); chromium (0.593-1.692); copper (175.882-245.321); manganese (bdl: 3.326); lead (0.221-0.263) and zinc (248.191-292.333). Some of the heavy metal concentrations obtained in water, sediment and catfish analyzed were above the permissible limit set by some National (DPR) and International organisations (WHO, FEPA and FAO). The pollution studies showed that lead, cadmium and chromium contaminated the surface water samples. Sediment from all sites showed low to considerable contamination by the heavy metals. The human exposure risk assessment of the metals showed that the total hazard index was less than one which indicates no probable adverse health effect from the consumption of fish from the ponds, although this case is different for Pb since there is no estimation of oral reference dose (RfDo) for lead according to EPA.

Investigation of hydrogen-air and acetylene-air flame propagation through porous media using infrared visualisation

One of the modern energy safety concerns is ensuring explosion safety when working with flammable gases. For this purpose, various methods are used, such as active chemical inhibitors and passive combustion suppression. The use of various porous materials is prevalent among passive methods for combustion suppression. This study focused on the experimental investigation of hydrogen-air and acetylene-air flame propagation through polyurethane foam and through the empty channel. The use of high-speed infrared camera enabled visualization of flame propagation inside the porous material. Two types of diagnostic channels were used with the dimensions of the diagnostic section 16 × 20 mm and 40 × 20 mm. The length of the foam was 120 mm. In hydrogen-air mixtures with 10 pores per inch (PPI) polyurethane foam the flame velocity was higher than in the empty section; with 30 PPI polyurethane foam the flame was quenched in the mixture with equivalence ratio ER = 0.3, but for mixtures with ER = 0.4 and ER = 0.5 the average flame velocity was higher than in the empty channel. In the acetylene-air mixtures flame velocity was usually lower in polyurethane foam and only reached the flame velocity in the empty channel with ER = 0.8 and 10 PPI foam. Critical Peclet numbers that allowed the flame to propagate through porous materials were calculated based on the obtained experimental data. The critical Peclet numbers were 23–24 for the hydrogen-air mixture and 37–38 for the acetylene-air mixture. The channel was open near the ignition point, which allowed the obtained results to be less dependent on the channel length. Information obtained in this work can be used to improve the means of ensuring explosion safety, including in the areas of nuclear power and transport using hydrogen.

Analysis of Cd and Cu Heavy Metal Content in Climbing perch (Anabas testudineus) Derived from Rawa Taliwang Lake, West Sumbawa Regency

Many species of fish in Rawa Taliwang Lake can be used as bioindicators. Climbing perch (Anabas testudineus) is a species of freshwater fish that is used as a bioindicator. The aims of this study were: Want to know the heavy metal content of Copper (Cu) and Cadmium (Cd) in Climbing perch from Rawa Taliwang Lake to enrich the Environmental Knowledge course material. A special benefit is to protect consumers who consume fish from heavy metal contaminants. The research was conducted in Rawa Taliwang Lake, which is an area that is submerged in water. Methods Data collection was carried out by determining 2 research stations, namely in the east and west of the lake. Next, fishing is done using gill nets. Fish samples were taken from 3 to 4 fish at each station. The fish species taken were Climbing perch (Anabas testudineus). Then each fish sample was put into a plastic bag and then stored in a sample box. The research sample was then analyzed in the West Nusa Tenggara Health, Testing and Calibration laboratory. The data analysis method was carried out by taking muscle tissue from Climbing perch and then analyzing the content of heavy metals in the form of Copper (Cu), and Cadmium (Cd) using an Atomic Absorption Spectrophotometer. Measurement of heavy metals in fish tissue was carried out by adding concentrated HNO3 and HClO4, heated at a temperature of 60-70ºC for 2-3 hours until the solution was clear. Ready samples were measured by AAS using an air-acetylene flame. The measurement results show the presence of heavy metals Copper (Cu) and Cadmium (Cd) in the fish tissue studied. The conclusion of this study is that the heavy metal content in Climbing perch  (Anabas testudineus) originating from Rawa Taliwang Lake to enrich the Environmental knowledge course material is; Copper (Cu) ranged from 0.067 ppm to 0.126 ppm, and Cadmium (Cd) ranged from 0.011 ppm to 0.016 ppm.

Концентрация алюминия и свинца в сыворотке крови потерпевших на мирной территории с черепно-мозговой травмой легкой и средней степени тяжести в остром и промежуточном периодах

Актуальность. Патогенез черепно-мозговой травмы (ЧМТ) многогранный и в значительной степени обусловлен развитием эндогенной интоксикации, которая приводит к накоплению в организме различных промежуточных и конечных продуктов метаболизма, в том числе и токсических металлов. Понимание основных путей патогенеза интоксикации алюминием и свинцом позволит разработать методы ранней диагностики, а также действенные меры по профилактике и лечению. Цель работы: изучить изменения показателей алюминия и свинца в сыворотке крови потерпевших на мирной территории с ЧМТ легкой и средней степени тяжести в остром и промежуточном периодах. Материалы и методы. Проведено определение содержания алюминия и свинца в сыворотке крови у 283 потерпевших на мирной территории с ЧМТ методом атомно-абсорбционной спектрофотометрии с использованием воздушно-ацетиленового пламени. Результаты. С учетом очевидных изменений содержания токсических микроэлементов в сыворотке крови потерпевших на мирной территории с ЧМТ легкой и средней степени тяжести в остром и промежуточном периодах можно говорить о наличии у них метаболических нарушений в ткани мозга, угнетении эндотелиальной функции сосудов и усилении процессов апоптоза. По нашему мнению, у указанных пациентов эндотелиальная дисфункция может рассматриваться как маркер сосудистой патологии. Выводы. Таким образом, исследования содержания токсических микроэлементов в сыворотке крови потерпевших на мирной территории с ЧМТ легкой и средней степени тяжести в остром и промежуточном периодах могут быть использованы в качестве диагностического и прогностического критериев течения травматической болезни головного мозга и с экспертными целями, а изучение основных путей патогенеза алюминиевой и свинцовой интоксикации позволит разработать методы их ранней диагностики, действенные меры по профилактике и лечению.

Study of toxic elements in propolis

There is a threat of heavy metals and toxic elements entering the beekeeping products in relation to the deterioration of the ecological situation. In this regard, a study of one of the most popular beekeeping products, propolis, from the territory of two regions of Russia (Ryazan Oblast and Krasnodar Krai) for the level of Pb, Cd, Sr and the toxic element As was undertaken. The studies were made from 2004 to 2019. The amount of elements was determined spectrophotometrically with an atomic absorption spectrophotometer Spectr AA 220FS. Lead, cadmium and strontium levels were determined using an air-acetylene flame on a gas atomizer. The level of arsenic was determined on a graphite oven of a spectrophotometer using a palladium modifier made by “Mersk”. The lead level in propolis was from 0 to 0.19 mg/kg that exceeds the threshold limit value by a factor of 1.2-12.3. The concentration of cadmium, strontium, arsenic in the studied propolis samples does not exceed the threshold limit value: 0-0.164 mg/kg, 2.1-21.01 mg/kg, 0-1.04 μm/kg, respectively. The accumulated experimental data indicate the need to adjust the threshold limit value (SanPiN 2.3.2. 1078-01) of lead level in propolis. The dynamics of propolis pollution with toxic elements was evaluated in the course of the research. The results of this evaluation confirmed the possibility of using propolis as a bioindicator of environmental pollution with heavy metals and toxic elements. It is necessary to monitor the propolis safety to determine its level of contamination with heavy metals and toxic elements, when using it as a source of biologically active compounds and as a raw material for Pharmacy (making extracts, tablets, ointments, syrups, suppositories, plasters).

Calcium monofluoride as a target molecule for determination of organic fluorine in gasoline and its components using high-resolution continuum source flame molecular absorption spectrometry

High-resolution continuum source molecular absorption spectrometry (HR-CS MAS) is widely applied to determine fluorine in various materials, and its graphite furnace option with calcium monofluoride as a target molecule is popular. However, up to now, the idea of using the molecule in flame molecular absorption spectrometry seemed impossible or impractical due to the expected low sensitivity and detectability. The following paper completely changes this view. The CaF molecule has been proven to be an excellent tool for determining organic fluorine in gasoline using flame molecular absorption spectrometry, giving benefits over previously used gallium monofluoride. The following favourable circumstances decide about it: 1) relatively high population of CaF molecules in preferable air-acetylene flame, 2) possibility of using oil calcium “standard” as a source of calcium, which is well dissoluble in both xylene (solvent) and gasoline, 3) extremely good stability of baseline in the used spectrum range, 4) relatively high freedom from spectral and chemical interferences and 5) possibility of summing of many pixels response. The analysis relies on simple sample dilution in xylene, with the addition of oil calcium “standard” to obtain 1500 mg L−1 Ca in measured solutions. Simplified standard addition calibration is used to overcome the effect of variability of samples (various physical properties and combustion characteristics). The signals of four CaF rotational “lines” are summed. The only undesirable spectral effect is a molecular absorption at the second “line” (606.0368 nm), which is attributed to the absorption by the CaOH molecule formed in the flame. The effect can be easily overcome by using the least square background correction, LSBC. The characteristic concentration and the detection limit for solutions are 6 and 0.6 mg L−1, respectively. The detection limit recalculated for the original sample is 2 mg kg−1 in the case of alkalyte, reformate and gasoline, while it is 6 mg kg−1 in the case of volatile isomerizate, mainly due to necessary higher sample dilution. The calibration curve is linear over at least two orders of magnitude. Heptafluorobutanol has been found a suitable standard. The agreement of the results of the proposed method and standard combustion ion chromatography is satisfactory.

Assessment of heavy metals concentration in soils and plants from electronic waste dumpsites in Lagos metropolis.

E-waste is a global environmental problem that must not be underestimated. To ascertain the environmental pollution status of electronic waste dumpsites, an assessment of seasonal variation in concentrations of heavy metals in the soils and plants in electronic waste dumpsites in Lagos metropolis was undertaken during the two major seasons (wet and dry seasons) in Nigeria. The soils and plants samples collected in August during the rainy season and December during the dry season were digested using aqua regia, a wet digestion method. The heavy metal concentrations were quantified with flame atomic absorption spectrophotometer (FAAS) fitted with a hollow cathode lamp (Perkin-Elmer AA Analyst 200) using an air-acetylene flame. The soil samples and the plants analyzed were found to have high concentrations of heavy metals. All the plants analyzed were identified and classified as excluders and accumulators of heavy metals based on their shoot/root quotients. The results obtained experimentally were analyzed using statistical and multivariate techniques. The soil quality of the study area was evaluated using correlation factor, pollution load index, and geoaccumulation index. The heavy metal assessment in comparison with the EU and Canadian standards for both agricultural and residential soils showed that the e-waste dumping sites are highly polluted. The results obtained for both the soil and plants analyzed confirmed the great impact of the hazardous components of e-waste on the ecosystem.

Content of Mobile Elements in the Soil and their Accumulation in the Shoots and Fruits of Highbush Blueberry (Vaccinium corymbosum L.) and Bogbillberry (V. uliginosum)

Vaccinium uliginosum L. is aboriginal plant species in Ukraine, and Vaccinium corymbosum L. is from the American continent but is widely cultivated in Europe and Ukraine for fruit production. The vegetative part of these plants is practically not used, and their chemical composition has not been studied in detail, although the native Europeans and Americans used the plants for medicinal purposes. Contents of selected elements were determined in samples of forest V. uliginosum L. shoots and fruits harvested in Western Ukraine and cultivated V. corymbosum L. (three cultivars) fruits and shoots. The atomic absorption spectrophotometry with sample aspiration in air-acetylene flame was used to analyze the metal concentration. Chemical analyses of shoots showed significantly greater content for essential elements (Cu, Zn, Mn, Co, Cr) than in fruits of both investigated species. In the fruits of V. corymbosum is much more Cu, Zn, Ni, Mn (2.13-3.17; 3.58-8.84; 0.74-1.18; 3.36-6.52 mgkg-1 DW) compare to V. uliginosum ones. V. corymbosum varieties differ significantly in content elements in the shoots and fruits (especially Co, Cr, Cu, Cd). Correlation between the concentrations of elements in shoots and fruits of V. corymbosum cultivars as well as in shoots and fruits of V. uliginosum and the mobile metal concentrations in soil of their growth were calculated, but direct connections were not found. The element composition of Vaccinium corymbosum shoots and fruits has proven to be promising tools.

Determination of Manganese(II) using Catalytic Hydrogen Wave (CHW) Technique in Environmental and Biological Samples

Background: A simple, low cost and highly sensitive catalytic hydrogen wave (CHW) method has developed for the investigation of Manganese(II) in ammonium 4-phenylpiperazine-1- dithiocarbamate and ammonium 4-benzylpiperidine-1-dithiocarbamate in various environmental and biological samples using D.C. polarography. This procedure was based on the reaction of Mn(II) in APP-DTC/ABP-DTC in the presences of NH4Cl-NH4OH medium at pH 6.6 and 7.2 respectively. The resulting oxidation signals were obtained at -0.78 V and -0.64 V vs SCE, owing to the CHWs. Different experimental conditions such as pH effects, background electrolyte (NH4Cl-NH4OH) effects and DTCs and Mn(II) ion effects have been studied. The current method was effectively employed for the testing of Mn(II) in different environmental and biological samples and attained recovery percentages (95-99%) are comparable to the Atomic Absorption Spectrophotometry (AAS) method. Methods: Direct current polarography, model CL-357 and CL-25 (Elico Private Ltd, Hyderabad, India), Shimadzu AA 6300 spectrometer furnished thru a deuterium background corrector and hollow cathode lamp, at corresponding wavelengths (resonance line) with an air acetylene flame. The experimental guidelines remained those suggested by the makers. Results: The effect of NH4Cl between 0.1 to 0.7 M on the nature of CHW at DME, maintaining the concentrations of Mn(II) at 4.0 ppm and DTC at 3.0 mM (APP-DTC/ABP-DTC) then adjusting the pH to 6.6/7.2 (APP-DTC/ABP-DTC). The polarograms were well-defined in NH4Cl of 0.4/0.5 M for APP-DTC/ABP-DTC. The peak height decreased beyond this concentration and therefore 0.4/0.5 M (APP-DTC/ABP-DTC) concentrations was kept for more analysis. At fixed concentration of DTC, (3.0 mM APP-DTC/ABP-DTC) and (0.4/0.5 M for APP-DTC/ ABP-DTC) NH4Cl adjusting the pH to 6.6/7.2 respectively the metal ion concentration of the Mn(II) was adjusted between 0.05 to 7.0 ppm and results of CHWs were studied. The peak current increased linearly with Mn(II) concentration in the range 0.05 to 4.0 ppm for both DTCs. However, the sensitivity of the method was more with APP-DTC/ABP-DTC because of strong complex of Mn(II) and increased catalytic activity. Conclusion: The developed CHW method is highly sensitive, simple and spontaneous for the analysis of Mn(II) in environmental and biological samples. The polarographic reduction of Mn(II) in aqueous solutions in the attendance of DTC displays a catalytic wave as a role of pH, concentration of supporting electrolyte and metal ion. The graphs of catalytic signals as a role of the concentration of dithiocarbamate shows that the signals do not vary linearly with the concentration of dithiocarbamate which the characteristic of Brdicka CHWs. It is presumed that the dithiocarbamate complexes with metal ions involve adsorption process and can be described by a Langmuir adsorption isotherm and the plot of CL/ip Vs CL should be linear. The CHW method is free from interference effect avoiding the removal stages which made towards placing among utmost sensitive methods for the analysis of Mn(II) in different Environmental and Biological samples.