Determination of total chromium by flame atomic absorption spectrometry after coprecipitation by cerium (IV) hydroxide

A method for the preconcentration of the total chromium based on coprecipitation with cerium (IV) hydroxide is proposed for determination of chromium by flame atomic absorption spectrometry. Different factors including carrier element amount, pH, sample volume and matrix ion effects for the precipitation were examined. The detection limit of the total chromium (k = 3, N = 15) was 0.18 μg l⁻¹. The presented method was applied for the determination of chromium in the wastewater samples from Kayseri and Nigde Organized Industrial Region-Turkey and in drinking water from our laboratory, Kayseri with satisfactory results (relative standard deviations below 8%, recoveries 95%). The analytical results obtained by the proposed method for certified copper sample was in good agreement with the certified value.     

Evaluation of metal contents of household detergent samples from Turkey by flame atomic absorption spectrometry

The concentrations of cadmium, copper, chromium, cobalt, iron, lead, manganese, nickel, and zinc in detergent samples from Kayseri, Turkey were determined by flame atomic absorption spectrometry. HClO₄ (10 mL)/HNO₃ (10 mL) mixture was used for the digestion of household detergent samples. The correctness of the analytical procedures was checked with standard addition–recovery tests in different detergent samples for the investigated metal ions. The concentration ranges of the elements in the detergent samples were found as 17.2–60.1, 11.1–40.1, 2.5–32.3, 8.1–10.5, 7.2–21.6, 9.8–17.9, 1.7–3.8, 12.5–22.5, and 2.0–5.8 μg/g for iron, manganese, zinc, copper, lead, cobalt, cadmium, nickel, and chromium, respectively. The values found in this work were compared with some other studies around the world conducted on detergent samples.     

Solid phase extraction of gold(III) on Amberlite XAD-2000 prior to its flame atomic absorption spectrometric determination

A solid phase extraction method for the determination of gold(III) at trace levels by flame atomic absorption spectrometer (FAAS) was developed. The method was based on retention of gold as chloro complexes through the Amberlite XAD-2000. The effect of some analytical parameters including hydrochloric acid concentration, sample volume, sample and eluent flow rates, eluent volume, eluent concentration and interfering ions on the recovery of gold(III) was investigated. The retention of gold(III) from 1.5 mol l⁻¹ HCl solution and the recovery of gold with 0.07 mol l⁻¹ NH₃ solution were quantitative (≥95%). The relative standard deviation (RSD) was calculated as 3.2% (n = 10). The detection limit for gold was 2 μg l⁻¹. The accuracy was checked with the determination of gold spiked an artificial seawater and a pure copper samples.     

Lead isotope ratios in lichen samples evaluated by ICP-ToF-MS to assess possible atmospheric pollution sources in Havana,Cuba

Epiphytic lichens, collected from 119 sampling sites grown over “Roistonea Royal Palm” trees, were used to assess the spatial distribution pattern of lead (Pb) and identify possible pollution sources in Havana (Cuba). Lead concentrations in lichens and topsoils were determined by flame atomic absorption spectrophotometry and inductively coupled plasma (ICP) atomic emission spectrometry, respectively, while Pb in crude oils and gasoline samples were measured by ICP-time of flight mass spectrometry (ICP-ToF-MS). Lead isotopic ratios measurements for lichens, soils, and crude oils were obtained by ICP-ToF-MS. We found that enrichment factors (EF) reflected a moderate contamination for 71% of the samples (EF > 10). The ²⁰⁶Pb/²⁰⁷Pb ratio values for lichens ranged from 1.17 to 1.20 and were a mixture of natural radiogenic and industrial activities (e.g., crude oils and fire plants). The low concentration of Pb found in gasoline (<7.0 μg L^?1) confirms the official statement that leaded gasoline is no longer used in Cuba.     

Investigation of heavy metal contaminations in the lower Sakarya river water and sediments

In this work, water and sediment samples were collected from three different stations located along the Sakarya river between May and September 2003. Lead, copper, chromium, zinc, nickel and cadmium concentrations were determined by using solvent extraction and flame atomic absorption spectrometric method. The results show that differences based upon sampling times, regions, sediment and water samples were observed. The mean levels of copper, nickel, chromium, lead, cadmium, zinc for sediment samples are; 4.630 μg g⁻¹, 13.520 μg g⁻¹, 8.780 μg g⁻¹, 2.550 μg g⁻¹, 9.990 μg g⁻¹ and for water samples are; 0.851 μg g⁻¹, 1.050 μg g⁻¹, 0.027 μg g⁻¹, 1.786 μg g⁻¹, 0.236 μg g⁻¹, 0.173 μg g⁻¹, respectively.     

Levels of Selected Metals in Canned Fish Consumed in Kingdom of Saudi Arabia

In the present paper, seven heavy metals (Pb, Cd, Ni, Cu, Zn, Cr and Fe) in canned salmon, sardine and tuna fish were determined by using atomic absorption spectroscopy. Cadmium and lead levels were determined by graphite tube AAS whereas Ni, Cu, Cr and Fe were determined by flame AAS. Analytical results were validated by spiking the samples with various concentrations of these metals for recovery. The metal contents, expressed in μg/g, wet weight, varied depending upon the specie studied. The levels of Pb ranged from 0.03–1.20 μg-g⁻¹ with an average of 0.313 μg-g⁻¹ for salmon; 0.03–0.51 μg-g⁻¹ with an average of 0.233 μg-g⁻¹ for tuna and 0.13–1.97 μg-g⁻¹ with an average of 0.835 μg-g⁻¹ for sardines. The levels of Cd ranged from 0.02–0.38 μg-g⁻¹ with an average of 0.161 μg-g⁻¹ for salmon; 0.07–0.64 μg-g⁻¹ with an average of 0.227 μg-g⁻¹ for tuna and 0.010–0.690 μg-g⁻¹ with an average of 0.183 μg-g⁻¹ for sardines. Comparative evaluation of these metals in three varieties of fish showed that average concentration of lead in sardines is about 4 times and Ni about 3 times higher as compared to tuna. Generally, the levels of these metals follow the order sardine > salmon > tuna. The data generated in the present study compared well with the similar studies carried out in different parts of the world. The results indicate that canned fish, in general and tuna in particular, have concentrations within permissible limits of WHO/FAO levels for these heavy metals. Therefore, their contribution to the total body burden of these metals can be considered as negligibly small.     

Plant Uptake/Bioavailability of Heavy Metals from the Contaminated Soil after Treatment with Humus Soil and Hydroxyapatite

Cellulose nitrate membrane filter was used for the preconcentration-separation of Cu, Co, Cd, Pb and Cr ions. The analyte ions were collected on the membrane filter by the aid of carmine. Then membrane filter was dissolved by using nitric acid. The levels of the analytes in the final solutions were determined by flame atomic absorption spectrometry (FAAS). The analytical parameters including pH, amounts of carmine, sample volumes etc. have been optimized. No influences have been observed from the matrix ions. The detection limits for analytes were in the range of 0.08 μg/l-0.93 μg/l. The validation of the procedure was checked by the analysis of standard reference sediment (GBW 07309). The present method has been successfully applied for the FAAS determinations of analyte ions in real samples including black tea and magnesium salts.     

Statistical source identification of metals in groundwater exposed to industrial contamination

Levels of selected metals Na, Ca, Mg, K, Fe, Mn, Cr, Co, Ni, Cd, Pb and Mn were estimated by flame atomic absorption spectrophotometry in groundwater samples from Kasur, a significant industrial city of Pakistan. Salient mean concentration levels were recorded for: Na (211 mg/l), Ca (187 mg/l), Mg (122 mg/l), K (87.7 mg/l), Fe (2.57 mg/l) and Cr (2.12 mg/l). Overall, the decreasing metal concentration order was: Na > Ca > Mg > K > Fe > Cr > Zn > Co > Pb > Mn > Ni > Cd. Significantly positive correlations were found between Na–Cr (r = 0.553), Na–Mn (r = 0.543), Mg–Fe (r = 0.519), Mg–Cr (r = 0.535), Pb–K (r = 0.506) and Pb–Ni (r = 0.611). Principal Component Analysis and Cluster Analysis identified tannery effluents as the main source of metal contamination of the groundwater. The present metal data showed that Cr, Pb and Fe levels were several times higher than those recommended for water quality by WHO, US-EPA, EU and Japan. The elevated levels of Cr, recorded as 21–42 fold higher compared with the recommended quality values, were believed to originate from the tanning industry of Kasur.     

Persistence and Dissipation Kinetics of Spiromesifen in Chili and Cotton

In a field study carried out at three different locations, the dissipation of spiromesifen on cotton and chili was studied and its DT₅₀, and DT₉₉ were estimated at each location. Spiromesifen was sprayed on chili at 96 and 192 g a.i. ha⁻¹ and cotton at 120 and 240 g a.i. ha⁻¹. Samples of chili fruits were drawn at 0, 1, 3, 5, 7, 10, 15, 21, 30 days after treatment and that of cotton seed and lint at first picking and harvest. Soil samples were drawn 30 days after treatment from 0 to 15 and 15 to 30 cm layer. Quantification of residues was done on GC–MS in Selected Ion Monitoring (SIM) mode in mass range 271–274 m/z. The LOQ of this method was found 0.033 μg g⁻¹, LOD being 0.01 μg g⁻¹. The DT₅₀ of spiromesifen when applied at recommended doses in chili fruits was found to be 2.18–2.40 days. Ninety-nine percent degradation was found to occur within 14.5–16.3 days after application. Residues of spiromesifen were not detected in cotton seed and lint samples at the first picking. In soil, no residues of spiromesifen were detectable 15 days after treatment.     

Seasonal Variation of the Particle Size Distribution of n-Alkanes and Polycyclic Aromatic Hydrocarbons (PAHs) in Urban Aerosol of Guangzhou, China

Seasonal aerosol samples have been collected by Andersen Hi-Vol pumping system equipped with a five stage cascade impactor and a backup filter (size range: 10–7.2 μ m, 7.2–3.0 μ m, 3.0–1.5 μ m, 1.5–0.95 μ m, 0.95–0.49 μ m, ≤0.49 μ m) in the Liwan district, Guangzhou. n-Alkanes were measured using gas chromatography and PAHs were measured using gas chromatography/mass spectrometry analysis. The bimodal log-normal distributions of n-alkanes and semi-volatile PAHs were found, while for non-volatile PAHs that was unimodal, so much as the mode of semi-volatile PAHs was similar with that of the particles. The n-alkanes and PAHs were preferably associated with fine particles. C _max (carbon number maximum) (C₂₂–C₂₆), CPI (carbon preference index) (1.12–1.21), U/R (unresolved to resolved components ratio) (7.42–10.7), wax% (0.9–3.12%) and the diagnostic ratios for PAHs revealed that vehicular emission was the major source of these organic compounds during the study periods, while the contribution of epicuticular waxes emitted by terrestrial plants was minor. CPI₂ (values for petrogenic hydrocarbons), CPI₃ (values for biogenic n-alkanes) and wax% revealed that the natural preferentially accumulated in the larger aerosol while the anthropogenic in the smaller. In addition, the different MMDs (mass median diameters) for n-alkanes and PAHs were observed in different seasons. The MMDs for n-alkanes and PAHs were higher in autumn/winter than those in spring/summer. The seasonal effect was related to the hydrocarbon content in the individual particulate fractions, showing a preferential association of n-alkanes and PAHs with larger particles in the autumn/winter season.     

Fractionation of Aluminum in Soil and Relation to Its Concentration in Fruits

Aluminum concentrations in the fruit samples taken from different regions were determined by atomic absorption spectrometry after dry ashing digestion. To identify the aluminum phases being most responsible for fruit-available aluminum, the soil samples near the fruit plants were also analyzed for aluminum by using various digestion and selective extraction reagents. The relation between the aluminum concentrations in fruits and in soil extracts was studied. The obtained aluminum concentrations in the fruits were in the range of 1.5 to 42.0 mg kg^-1 on dry weight basis. It was observed that the aluminum concentrations of morello cherry(R² = 0.79) and mulberry (R² = 0.99) were correlated to the aluminum concentrations in citric acid extracts of the soils. While the aluminum concentrations of the EDTA and acetic acid extracts in some soils samples include 35% and 25% of total aluminum, respectively, the other soils contain only 1–2%.     

Total Mercury Distribution in Different Tissues of Frigate Tuna (Auxis thazard thazard) from the Atlantic Coastal Waters of Ghana, Gulf of Guinea

Total mercury concentrations in different tissues of frigate tuna fish (Auxis thazard thazard) was determined by the cold vapour atomic absorption spectrometry technique using an automatic mercury analyzer. A mixture of HNO₃, HClO₄ and H₂SO₄ was used for complete oxidation of organic tissue. The concentration of mercury obtained was in the order Gills < Stomach < Gonads < Intestine < Heart < Duodenum < Liver < Muscle. The concentration of total mercury detected in the edible muscle tissue of the tuna fish tested ranged from 0.044 to 0.201 μg g⁻¹ (mean = 0.108 μg g⁻¹) wet weight. These levels are all within the maximum allowed/recommended level in fish (0.5 μg g⁻¹ wet weight) set by the Food and Agriculture Organisation/World Health Organisation (FAO/WHO) and are therefore unlikely to constitute any significant mercury exposure to the general population because of consumption of tuna fish. The results of the study suggest a relatively clean marine environment that has not been significantly impacted by mercury contamination probably due to minimal industrial activity in the region.     

Hydrogen Peroxide and Ultraviolet Irradiations in Water Treatment

Trihalomethanes (THMs) the by-products of chlorination in water treatment are recognised as a threat to public health due to their carcinogenicity. The photodegradation of THMs using hydrogen peroxide has been found to give increased removal efficiency and the outcome of the study may find, its application in designing a unit process for water treatment. Batch experiments were carried out using UV lamp of 83 W and 40% w/w Hydrogen peroxide (H₂O₂) in test waters between 2.5–10 pH range of chloroform, bromodichloromethane, dibromochloromethane and bromoform at 50–200 μg L⁻¹ initial concentration. 92–100% removal of chloroform, bromodichloromethane, dibromochloromethane and bromoform were found with 0.1% of H₂O₂ and 90 min of UV exposure.     

Status of insecticide contamination of soil and water in Haryana, India

Twelve samples each of soil and ground water were collected from paddy-wheat, paddy-cotton, sugarcane fields and tube wells from same or near by fields around Hisar, Haryana, India during 2002–2003 to monitor pesticide residues. Residues were estimated by GC-ECD and GC-NPD systems equipped with capillary columns for organochlorine, synthetic pyrethroid and organophosphate insecticides. In soil, HCH (0.002–0.051 μg g⁻¹), DDT (0.001–0.066 μg g⁻¹), endosulfan (0.002–0.039 μg g⁻¹) and chlordane (0.0002–0.019 μg g⁻¹) among organochlorines, cypermethrin (0.001–0.035 μg g⁻¹) and fenvalerate (0.001–0.022 μg g⁻¹) among synthetic pyrethroids and chlorpyriphos (0.002–0.172 μg g⁻¹), malathion (0.002–0.008 μg g⁻¹), quinalphos (0.001–0.010 μg g⁻¹) among organophosphates were detected. Dominant contaminants were DDT, cypermethrin and chlorpyriphos from the respective groups. In water samples, HCH, DDT, endosulfan and cypermethrin residues were observed frequently. Only chlorpyriphos among organophosphates was detected in 10 samples. On consideration of tube well water for drinking purpose, about 80% samples were found to contain residues above the regulatory limits.     

Facile and Sensitive Spectrophotometric Determination of Carbosulfan in Formulations and Environmental Samples

Facile, selective and sensitive spectrophotometric method has been developed for the determination of carbosulfan in insecticidal formulations, fortified water, food grains, agriculture wastewater and soil samples with newly synthesized reagents. The method was based on acid and alkaline hydrolysis of the carbosulfan pesticide, and the resultant hydrolysis product of carbosulfan was coupled with 2,6-dibromo-4-methylaniline to give a yellow color product with λ _max of 464 nm or interaction with 2,6-dibromo-4-nitroaniline to produce yellow colored product with λ _max of 408 nm or coupling with 2,4,6-tribromoaniline to form red colored product has a λ _max of 471 nm. Under optimal conditions, Beer’s law range for 2,6-dibromo-4-methylaniline (DBMA) was found to be 0.2–12.0 μg ml⁻¹, 0.6–16.0 μg ml⁻¹ for 2,6-dibromo-4-nitroaniline (DBNA) and 0.4–15.0 μg ml⁻¹ for 2,4,6-tribromoaniline (TBA). The molar absorptivity of the color systems were found to be 3.112 × 10⁴ l mol⁻¹ cm⁻¹ for DBMA, 3.214 × 10⁴ l mol⁻¹ cm⁻¹ for DBNA and 3.881 × 10⁴ l mol⁻¹ cm⁻¹ for TBA. Sandell’s of the color reactions are 0.013 μg cm⁻² (DBMA), 0.012 μg cm⁻² (DBNA) and 0.011 μg cm⁻² (TBA) respectively. The effect of the non-target species on the determination of carbosulfan was studied to enhance the selectivity of the proposed methods. The formation of colored derivatives with the coupling agents is instantaneous and stable for 28, 30, and 26 h. Performance of the proposed methods were compared statistically in terms Student’s F and t-tests with the reported methods. An erratum to this article can be found at     

Determination of traces of copper and zinc in honeys by the solid phase extraction pre-concentration followed by the flame atomic absorption spectrometry detection

A simple and fast solid phase extraction procedure was developed to pre-concentrate traces of Cu and Zn prior to their determination in honey samples by flame atomic absorption spectrometry. The sample preparation included dissolution of honey samples and the passage (at 20 ml/min) of resulting 10 % m/v solutions (100 ml) through Dowex 50W?×?8-400 resin beds in order to quantitatively retain Cu and Zn and separate them from the glucose and fructose matrix. Enriched Cu and Zn traces were recovered with 5.0 ml of a 3.0 mol/l HCl solution and quantified by flame atomic absorption spectrometry. The procedure proposed was used to analyze sixty nine commercially available and freshly ripened honey samples coming from the Lower Silesia region (Poland). It enabled to measure Cu and Zn within the range of 0.01–1.42 and 0.03–15.38 μg/g, respectively, with precision better than 4 %. Accuracy, assessed on the basis of the recovery test and the comparison of results with those obtained using wet digestion and inductively coupled plasma optical emission spectrometry, was ranged from ?4 % to +6 %. Detection limits of Cu and Zn achieved with this method were 5 and 7 ng/g, respectively.     

Solid-phase extraction and separation procedure for trace aluminum in water samples and its determination by high-resolution continuum source flame atomic absorption spectrometry (HR-CS FAAS)

In the present study, a separation/preconcentration procedure for determination of aluminum in water samples has been developed by using a new atomic absorption spectrometer concept with a high-intensity xenon short-arc lamp as continuum radiation source, a high-resolution double-echelle monochromator, and a charge-coupled device array detector. Sample solution pH, sample volume, flow rate of sample solution, volume, and concentration of eluent for solid-phase extraction of Al chelates with 4-[(dicyanomethyl)diazenyl] benzoic acid on polymeric resin (Duolite XAD-761) have been investigated. The adsorbed aluminum on resin was eluted with 5 mL of 2 mol L^-1 HNO₃ and its concentration was determined by high-resolution continuum source flame atomic absorption spectrometry (HR-CS FAAS). Under the optimal conditions, limit of detection obtained with HR-CS FAAS and Line Source FAAS (LS-FAAS) were 0.49 μg L^?1 and 3.91 μg L^?1, respectively. The accuracy of the procedure was confirmed by analyzing certified materials (NIST SRM 1643e, Trace elements in water) and spiked real samples. The developed procedure was successfully applied to water samples.     

Air Pollution and Heat Exposure Study in the Workplace in a Glass Manufacturing Unit in India

Air pollution in the workplace environment due to industrial operation have been found to cause serious occupational health hazard. Similarly, heat stress is still most neglected occupational hazard in the tropical and subtropical countries like India. The hot climate augments the heat exposure close to sources like furnaces. In this study an attempt is made to assess air pollution and heat exposure levels to workers in the workplace environment in glass manufacturing unit located in the State of Gujarat, India. Samples for workplace air quality were collected for SPM, SO₂, NO₂ and CO₂ at eight locations. Results of workplace air quality showed 8-hourly average concentrations of SPM: 165–9118 μg/m³, SO₂: 6–9 μg/m³ and NO₂: 5–42 μg/m³, which were below the threshold limit values of workplace environment. The level of CO₂ in workplace air of the plant was found to be in the range 827–2886 μg/m³, which was below TLV but much higher than the normal concentration for CO₂ in the air (585 mg/m³). Indoor heat exposure was studied near the furnace and at various locations in an industrial complex for glass manufacturing. The heat exposure parameters including the air temperature, the wet bulb temperature, and the globe parameters were measured. The Wet Bulb Globe Temperature (WBGT), an indicator of heat, exceeded ACGIH TLVs limits most of the time at all the locations in workplace areas. The recommended duration of work and rest have also been estimated.     

Heavy metals in the liver and muscle of <Emphasis Type="Italic">Micropogonias manni</Emphasis> fish from Budi Lake,Araucania Region,Chile: potential risk for humans

The concentrations of cadmium, lead, manganese and zinc were determined in the fish species Micropogonias manni captured in Budi Lake, Araucanía Region (Chile). The measurements were made by atomic absorption spectroscopy, and the analysis considered the sex, weight and size of the species; the representative samples were taken from the liver and muscle tissue. The method was validated using certified reference material (DOLT-1). The ranges of concentrations found in the muscle tissue were: Cd, not determinate (n.d.)–0.26; Pb, n.d.–1.88; Mn, 0.02–12.17 and Zn, 0.48–39.04 mg kg⁻¹ (dry weight). The concentrations in muscle tissue were generally lower than those found in the liver. With respect to the average concentrations recorded for each metal in the edible part of the fish (muscle tissue), it was found that the levels of Cd, Pb, Mn and Zn are within the ranges published by other authors in similar works and below the maximum concentration limits permitted by current legislation (FAO/WHO 2004; EU 2001) and do not constitute a health hazard for consumers of this species. The results were subjected to statistical analysis to evaluate the correlations between the content of the various metals and the sex, weight and size of each sample.