Interlaboratory Comparison of Analyses for Heavy Metals in Clam Tissue

1986 ◽  
Vol 69 (5) ◽  
pp. 863-868
Author(s):  
Marilyn R Hendzel ◽  
Bruce W Fallis ◽  
Brigitte G E Demarch

Abstract Results are reported for an interlaboratory study conducted to assess the reproducibility of analyses for lead, copper, cadmium, and zinc. The 10 participating laboratories analyzed 2 samples of freeze-dried clam tissue and 1 disguised sample of NBS Oyster Tissue. Interlaboratory variations were observed for all metals, although the methods yielded reproducible data for Cu and Zn with average interlaboratory coefficients of variation of 15 and 11%, respectively. The performance of methods used for Cd and, more so, for Pb was less than satisfactory. Cadmium levels in the 3 samples ranged from about 0.7 to 3.7 ppm with an average interlaboratory coefficient of variation (CV) of 24%. Lead levels in the 3 samples were about 0.5 ppm with an interlaboratory CVof 68%. Some laboratories' results were consistently high or low but data were insufficient to relate these trends to one particular variable. Results from this study were compared with 5 other studies reported in the literature since 1980. Coefficients of variation from all studies were comparable for samples with similar metal concentrations

1998 ◽  
Vol 55 (3) ◽  
pp. 688-703 ◽  
Author(s):  
Luc Janssens de Bisthoven ◽  
Jaap F Postma ◽  
Peter Parren ◽  
Klaas R Timmermans ◽  
Frans Ollevier

Levels of Cd, Pb, Cu, and Zn were measured in fourth-instar Chironomus gr. thummi and in three sediment fractions of Belgian lowland rivers, extracted with 1 M NH4-acetate, 1 M HCl, and 70% HNO3 - 30% H2O2. The percentages of deformed larvae and the mean population severities (MPS) of deformity for the head structures were compared by means of Pearson and linear and polynomial regressions against the metal concentrations in the different compartments. All correlations found were positive. Mentum deformities correlated with all lead fractions (MPS) and the larval copper fraction (percent deformed), while the pecten epipharyngis deformities correlated with the sediment lead fractions and the HCl fraction of copper. Premandible deformities correlated with the copper sediment HNO3-H2O2 fraction and with extreme values of cadmium and zinc. The study demonstrated a variety of deformity response curves to trace metals. At one site, higher lead concentrations were found in larvae with a deformed mentum, compared with normal larvae. Mentum deformities appeared to be potential predictors of lead levels in the sediments and the larvae, while pecten epipharyngis deformities may be an indicator of lead and copper in the sediments.


2019 ◽  
Author(s):  
Chem Int

A significant flux of heavy metals, among other toxins, reaches the lungs through smoking. This study reports Cd, Pb, Cu and Zn contents in tobacco of 11 brands of cigarette commonly sold in Ethiopia. The heavy metals were determined by atomic absorption spectrophotometry after wet digestion of cigarette tobacco using HNO3 and H2O2. The concentration of trace metals in the cigarettes ranged (mean) (μg/g), Cd: 1.3−7.6 (2.48±0.32), Pb: 0.50−12.50 (6.24±2.2), Cu: 2.89−25.35 (13.70±4.12) and Zn: 24.40−62.55 (36.22±7.50) while Ni was not detected in all the eleven brands of cigarettes. Comparable levels of trace metals were obtained in the tobacco of both imported and Ethiopian cigarettes. The average trace metal contents of cigarettes available in Ethiopia were Cd 1.82±0.39, Pb 4.23±0.97, Cu 10.2±3.1 and Zn 28.2±7.8 μg/cigarette and a person who smokes 20 cigarettes per day is estimated to increase his/her daily Cd, Pb, Cu and Zn retention by approximately 0.036, 0.085, 0.204, 0.564 mg/day, respectively. The results indicate that smoking and exposure to cigarette smoke is a serious problem to be taken into account when carrying out epidemiological studies on human exposure to trace metals.


Author(s):  
Katya Peycheva ◽  
Katya Peycheva ◽  
Mona Stancheva ◽  
Mona Stancheva ◽  
Stanislava Georgieva ◽  
...  

In this study, the ecosystem marine water-sediment-biota was investigated and the pollution was assessed. The concentrations of eight elements were determined in marine water, sediments and four fish species collected from Black Sea (Varna), Bulgaria during 2013. Marine water recorded the highest concentrations of Zn (15-22 μg/L), As (1.1–1.2 μg/L) and Pb (0.7-0.8 μg/L) while Zn (31-52 μg/g), Pb (21-29 μg/g) and Cu (20-34 μg/g) and show the highest concentrations in sediments. Water and sediments showed similar spatial distribution patterns for the highest mean values of the different metals. In the analysed fish species, the highest concentration of the metals Cu and Zn were found in Trachurus Mediterrneus (0.42 mg/kg w.w) and in Sprattus Sprattus (12.7 mg/kg w.w), respectively while the heavy metals As and Hg were found with maximum values in Pseta Maxima (3.99 mg/kg w.w and 0.08 mg/kg w.w respectively). The results from this study were compared with our data for a previous period (2004-2006) and they show decrease in the levels of heavy metal.


Plants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 841
Author(s):  
Marina Burachevskaya ◽  
Saglara Mandzhieva ◽  
Tatiana Bauer ◽  
Tatiana Minkina ◽  
Vishnu Rajput ◽  
...  

The presence of heavy metals in the soil could impose serious problems on soil-plant systems due to the accumulation of heavy metals in plants. Even vital elements such as Cu and Zn have a toxic effect in the case of excessive intake by living organisms. The present work aimed to investigate the content of loosely bound (exchangeable, complexed, and specifically sorbed) compounds of Cu and Zn and their availability to spring barley (Hordeum sativum distichum) in contaminated Haplic Chernozem soil under the conditions of a model experiment (five approximate permissible concentrations (APC) and 10 APC of metal). Changes in the bioavailability of the metals upon application of carbon sorbents were observed. An increase in loosely bound metal compounds has been shown under conditions of soil contamination with metals (up to 57% of the total content). The increase in the availability of Cu in the soil was mainly due to the formation of complexed metal forms with organic matter (up to 17%). The availability of Zn was found to be associated with an increase in exchangeable (up to 21%) and specifically sorbed compounds (up to 27%). Granular activated carbon (GAC) and biochar have high sorption properties. A decrease in the content of loosely bound compounds of metals was established, especially in the most mobile forms such as exchangeable and complexed forms. The introduction of sorbents into the soil opened up a new venue for binding heavy metals in situ, eventually leading to a decrease in their bioavailability. The inactivation of Cu and Zn in the soil upon the application of sorbents led to a decrease in metal absorption by spring barley. The highest efficiency of biochar application was established at a dose of 2.5% and 5% in soil contaminations of 5 APC and 10 APC of Cu or Zn. The efficiency of the use of sorbents was more influenced by the dose of application than by the type of sorbent. There was no significant difference between biochar and GAC. Stabilization and inactivation of metals may improve soil fertility and plant growth.


2015 ◽  
Vol 73 (4) ◽  
pp. 890-898 ◽  
Author(s):  
Huimin Wu ◽  
Meng Li ◽  
Lei Zhang ◽  
Chao Sheng

Thermal hydrolysis (TH) has been used to improve anaerobic digestion performance as well as the stability of heavy metals in sludge. Because the toxicity of heavy metals is closely related to both the concentration and the chemical speciation, more exhaustive studies on speciation distribution are urgently needed. This research aimed to investigate the effects of TH treatment (especially the time and temperature) on the concentration and stability of heavy metals in sludge, and to define the optimal TH conditions. The TH experiment indicated that the content of the stable form of Cu and Zn reached 83% and 47.4%, respectively, with TH at 210°C and 30 min. Compared with the raw sludge, the proportion of Cu and Zn increased by 11.88% and 7.3%, respectively. Results indicated that the heavy metals were combined with sludge in a more stable form with the pretreatment of TH, which improved the stability of heavy metals.


2010 ◽  
Vol 134 (11) ◽  
pp. 1685-1691
Author(s):  
Glenn E. Palomaki ◽  
George J. Knight ◽  
Geralyn Lambert-Messerlian ◽  
Jacob A. Canick ◽  
James E. Haddow

Abstract Context.—We initiated a voluntary, self-funded interlaboratory comparison program in the fall of 2005 because no proficiency testing program was available to laboratories in North America offering first-trimester, combined serum and ultrasound, Down syndrome screening. Objectives.—To evaluate the first 4 years of the interlaboratory comparison program against stated goals, to identify areas of concern, and to create new initiatives as indicated. Design.—Five serum samples are distributed 3 times a year to be tested for pregnancy-associated plasma protein A, human chorionic gonadotropin or its β subunit, and dimeric inhibin-A; participants convert these results into multiples of the median. Patient histories include nuchal translucency information that enables the calculation of the risk of Down syndrome. Also included are educational components linked to interlaboratory comparison program results. Assessment of integrated (first- and second-trimester markers) risks is accomplished by having participants combine interlaboratory comparison program results with their results from a second-trimester proficiency testing program administered by the College of American Pathologists. Results.—The precision profile for pregnancy-associated plasma protein A shows decreasing coefficients of variation with increasing pregnancy-associated plasma protein A concentrations and multiples of the median (25% to 11% and 30% to 15%, respectively). In contrast, coefficients of variation are a relatively constant 12% throughout the entire range of human chorionic gonadotropin results. On a logarithmic scale, the median coefficient of variation of the risk of Down syndrome is 9%. Conclusions.—Participants in the interlaboratory comparison program reliably measure analytes, compute multiples of the median, and calculate consistent Down syndrome risks. Assays for the measurement of pregnancy-associated plasma protein A are not standardized and are less precise than those for human chorionic gonadotropin. Participants calculate reliable median equations given sonographer-specific sets of paired crown-rump length and nuchal translucency measurements.


2009 ◽  
Vol 66 (3) ◽  
pp. 361-367 ◽  
Author(s):  
Gustavo Souza Valladares ◽  
Otávio Antônio de Camargo ◽  
José Ruy Porto de Carvalho ◽  
Alessandra Maria Cia Silva

Agricultural management with chemicals may contaminate the soil with heavy metals. The objective of this study was to apply Principal Component Analysis and geoprocessing techniques to identify the origin of the metals Cu, Fe, Mn, Zn, Ni, Pb, Cr and Cd as potential contaminants of agricultural soils. The study was developed in an area of vineyard cultivation in the State of São Paulo, Brazil. Soil samples were collected and GPS located under different uses and coverings. The metal concentrations in the soils were determined using the DTPA method. The Cu and Zn content was considered high in most of the samples, and was larger in the areas cultivated with vineyards that had been under the application of fungicides for several decades. The concentrations of Cu and Zn were correlated. The geoprocessing techniques and the Principal Component Analysis confirmed the enrichment of the soil with Cu and Zn because of the use and management of the vineyards with chemicals in the preceding decades.


2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Saeed Shanbehzadeh ◽  
Marzieh Vahid Dastjerdi ◽  
Akbar Hassanzadeh ◽  
Toba Kiyanizadeh

This study was carried out to examine heavy metals concentration in water and sediment of upstream and downstream of the entry of the sewage to the Tembi River, Iran. Samples were collected from upstream and downstream and were analyzed for Cd, Cr, Cu, Fe, Pb, Ni, and Zn by atomic absorption spectrophotometer. The results indicated that the average concentration of the metals in water and sediment on downstream was more than that of upstream. The comparison of the mean concentrations of heavy metals in water of the Tembi River with drinking water standards and those in the water used for agriculture suggests that the mean concentration of Cu and Zn lies within the standard range for drinking water and the mean concentration of Mn, Zn, and Pb lies within the standard range of agricultural water. The highest average concentration on downstream for Pb in water and for Mn in sediment was 1.95 and 820.5 ppm, respectively. Also, the lowest average concentration on upstream was identified for Cd in water and sediment 0.07 and 10 ppm, respectively. With regard to the results, it gets clear that using the water for recreational purposes, washing, and fishing is detrimental to human health and the environment.


2019 ◽  
Vol 38 (03) ◽  
Author(s):  
Kiran Bala ◽  
Aradhita Barmanray

Present study was directed to analyze and compare the bioactive compounds (total phenols, total anthocyanins), vitamins (ascorbic acid, β-carotene, vitamin A), minerals including Ca, Mg, Na, P, K, Fe, Cu, Zn, Co, Mn and heavy metals (Cd, Hg, Pb) of freeze-dried (lyophilized) phalsa pulp and seed powder. In lyophilized pulp powder (LPP) higher amount of total phenols (78.11 mg/100g), total anthocyanin (82.94 mg/100g), ascorbic acid (5.21 mg/100g), β-carotene (0.54 µg/100g), vitamin A (0.89 I.U.) were observed than lyophilized seed powder (LSP). Na, K, Mg and Co (0.41, 0.39, 1.08, 0.46 mg/100g, respectively) were higher in LPP as compared to LSP (0.29, 0.11, 0.76 and 0.40 mg/100g, respectively) whereas, Ca, P and Cu were detected more in LSP. This study opens the prospect of using dry phalsa powder in the preparation of various nutraceutical and functional foods for their therapeutic as well as prophylactic purposes.


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