scholarly journals Accumulation of heavy metals by some solitary tunicates

1978 ◽  
Vol 56 (4) ◽  
pp. 547-551 ◽  
Author(s):  
Gordon P. Danskin

The vanadium contents of eight species of solitary ascidians for which quantitative data are lacking are reported. It is observed that the occurrence of the metal within the class does not conform to taxonomic groups, but instead occurs sporadically throughout. For example, the phlebobranch Chelyosoma productum was observed to contain 800 ppm vanadium, whereas in a second member of the same family. Corella willmeriana, the metal could not be detected. Corella willmeriana contained a substantial iron concentration. The stolidobranch Boltenia villosa was found to contain vanadium at a level previously observed only among the phlebobranchs.The vanadium content of Ciona intestinalis shows a linear dependence upon the dry weight of the animal, and can be estimated from a concentration value of ~ 90 μg vanadium per gram dry weight, independent of the size class of the animal. No significant seasonal variation in the vanadium concentration of C. intestinalis was observed.

2021 ◽  
Vol 910 (1) ◽  
pp. 012114
Author(s):  
Mishaal Ali Mohammed

Abstract The research included a study on the presence of some heavy metals, including copper, iron and zinc in some medicinal plants circulating in the city of Mosul, as well as the study of the presence of cyanide in some other plants, when measuring the concentration of iron in saffron was less concentrated among plants of 0.797 mg/kg, followed by anise 7.3417 mg/kg, followed by mint 10.87 mg/kg. Kg and high concentrations appeared in the coriander plant, where the iron concentration was 486.6 mg/kg, ginger bread 396.49 mg/kg and corn 200.1 mg/kg and Marjoram 154.2 mg/kg, either Measuring the concentration of potters in medicinal plants in saffron plant was the lowest concentration of all plants used in the study and was 0.304 mg/kg followed by anise 7.8 mg/kg, followed by oranges 17.58 mg/kg, and high concentrations of coriander 179.2 mg/kg, ginger 111.3 mg/kg, while measuring of the concentration of copper in the medicinal plants used in the study the ratio of copper in saffron was low and amounted to 0.377 mg/kg (Dry weight), the highest concentration of copper was in the coriander plant, which was 120.922 mg/kg, ginger copper concentration was 50.78 mg/kg, and for the rest of the plants the concentration of copper ranged from (2.93 to 36.1) 22 mg/kg), while when measuring the iron ratio in the medicinal plants used in the study, and in a study The concentration of cyanide in plants (diphtheloide, apple seeds, perfalathseeds, henna seeds, castor seeds) by Spectrophotometer has been obtained different cyanide concentrations in these plants in the diphtherty the highest ratio of cyanide is 71.4 micrograms/30g (dry weight) followed by castor seeds 64.05 micrograms/30g, followed by henna seeds 31.36 mcg/30g, while in apple seeds the concentration of cyanide was 29.6 μg/30g and orange seeds 10.95 mcg/30g.


1963 ◽  
Vol 03 (02) ◽  
pp. 175-182 ◽  
Author(s):  
Bo Bergman ◽  
Rune Söremark

SummaryBy means of neutron activation and gamma-ray spectrometry the concentrations in the human mandibular articular disc of the following elements have been determined: Na, Mn, Cu, Zn, Rb, Sr, Cd, W, and Au. The discs were obtained at necropsy from seven men and nine women, ranging in age from 56 to 71 years.The activation was carried out in a thermal neutron flux of about 1.7 XlO12 neutrons × cm−2 × sec.−1 for about 20 hours. A chemical group separationwas performed before the gamma-ray spectrometry. Quantitative data based on the dry weight of the cartilage samples were obtained by comparing the photo-peak area of the identified elements with those of appropriate standards.


Foods ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 649
Author(s):  
Estefanía Noriega-Fernández ◽  
Izumi Sone ◽  
Leire Astráin-Redín ◽  
Leena Prabhu ◽  
Morten Sivertsvik ◽  
...  

The aim of this work was to evaluate the potential of ultrasound (US), alone or in combination with mild heating and/or EDTA towards reduction of As, Cd, I, and Hg content of Laminaria hyperborea. Concentrations of As, Cd, I, and Hg of 56.29, 0.596, 7340, and <0.01 mg kg−1 of dry weight, respectively, were found in L. hyperborea blades. Treatment with US at 50 °C increased approx. 2-fold the amount of As released, although did not affect significantly the content of Cd or I, as compared to control (no US) samples. Reducing the temperature to 8 °C significantly decreased the effect of US, but heating at 80 °C did not cause a significant effect as compared to treatments at 50 °C. On the other hand, treatment with 0.1 N EDTA at 50 °C enhanced the percentage of Cd released by approximately 7-fold, regardless of sonication. In the present work, the combination of US and EDTA at 50 °C for 5 min led to a significant reduction of the As (32%), Cd (52%) and I (31%) content in L. hyperborea, thus improving the product’s safety for consumers.


2021 ◽  
Vol 11 (4) ◽  
pp. 1856
Author(s):  
Masato Honda ◽  
Xuchun Qiu ◽  
Suzanne Lydia Undap ◽  
Takeshi Kimura ◽  
Tsuguhide Hori ◽  
...  

We investigated the pollution levels of 6 heavy metals and 29 dioxins (polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs)) in intertidal and supratidal zones by using wharf roaches (Ligia spp.) collected from 12 sampling sites on the coast of Northeast Japan from November 2011 to June 2012. The total concentrations of heavy metals ranged from 177 to 377 µg/g-dry weight (dw), and the predominant metals were copper, zinc, and aluminum. The order of the detected level of heavy metals was zinc > aluminum > copper > cadmium > lead > chromium, and this trend was similar to a previous report. The total toxic equivalent (TEQ) value of the PCDD/Fs ranged from less than the limit of detection (<LOD) to 2.33 pg-TEQ/g-dw, and the predominant congener was octachlorodibenzodioxin (<LOD to 110 pg/g-dw). Compared with PCDD/Fs, DL-PCBs were detected at a predominantly higher level (total TEQ value: 0.64–27.79 pg-TEQ/g-dw). Detected levels of dioxins, especially DL-PCBs in the wharf roach, were like those in the bivalves. These results indicate that the wharf roach could reflect heavy metals and dioxin pollution in the supratidal zones and is a suitable environmental indicator for these environmental pollutants. This is the first study to investigate heavy metals, PCDD/Fs, and DL-PCBs pollution in coastal isopods in Japan.


Author(s):  
Elisa Serviere-Zaragoza ◽  
Salvador E. Lluch-Cota ◽  
Alejandra Mazariegos-Villarreal ◽  
Eduardo F. Balart ◽  
Hugo Valencia-Valdez ◽  
...  

In the Gulf of California; mineral deposits have contributed to high metal contents in coastal environments. This study examined cadmium; lead; copper; zinc; and iron contents in three fish species; Kyphosus vaigiensis (herbivore), Stegastes rectifraenum (omnivore), and Balistes polylepis (carnivore) at two mining sites. Metal concentrations were analyzed by atomic absorption spectrophotometry and stable nitrogen and carbon isotopes were estimated using mass spectrophotometry. Also, we assessed the risk to human health from the consumption of these three species based on permissible limits; although only two of them (Kyphosus and Balistes) are consumed as food. Metal concentrations differed among fish species; except for iron. The highest concentrations of metals were not always recorded in the species at the highest trophic level; i.e., Balistes. The highest concentrations (dry weight) recorded were cadmium (0.21 ± 0.03 µg g−1) and lead (1.67 ± 0.26 µg g−1), in S. rectifraenum; copper (1.60 ± 0.49 µg g−1) and zinc (67.30 ± 8.79 µg g−1), in B. polylepis; and iron (27.06 ± 2.58 µg g−1), in K. vaigiensis. Our findings show that each element accumulates differently in particular marine organisms; depending on the physiology of the species and the biogeochemistry of its habitat; which in turn is affected by the anthropogenic activities in adjacent areas. No risk of heavy metals toxicity is expected from the human consumption of the species and sites studied


2011 ◽  
Vol 138-139 ◽  
pp. 1149-1155 ◽  
Author(s):  
Yi Dong Guan ◽  
Ye Hong Du ◽  
Zhen Dong Li ◽  
An Cheng Luo

This paper reports the concentration of heavy metals (Cr, Cu, Zn, Cd and Pb) in the soils and rices surrounding the abandoned rural waste dumping sites in Ningbo. Igeo (geoaccumulation index) was calculated to assess the contamination degree of heavy metals in soils. The mean contents of Cr, Cu, Cd, Zn and Pb of soils were 33.3, 24.1, 1.5, 118.9 and 45.6 mg/(kg DW) (dry weight), respectively. All of them were much higher than that of the reference value (i.e. CK), but there were no coherent trend of the metal contents within 1-120m distance from the dumping site. Igeo of heavy metals reveals the order of Cd>Cu>Cr>Pb>Zn, and the contamination assessment of soils using Igeo indicate the moderate Cd pollution, while the soils were unpolluted-moderately overall by Cr, Cu, Zn as well as Pb. The heavy metal contents in root, stem & leaf and rice grains were all remarkable higher than that of the CK at 20-120 m distances, and the heavy metal contents in root were evidently much higher than other plant parts, while those in rice grain were lowest, indicating the great bioaccumulation trend of heavy metals. Although the metal contents in the rice grain were within the legislation limit, its bioaccumulation trend of heavy metals was remarkable, whose contents were 4.38-fold for Cr, 1.76-fold for Cu, 1.28-fold for Zn, 2.67-fold for Cd and 3.03-fold for Pb higher than that of reference value, respectively. Finally, we proposed a decentralized in-situ restoration approach for the dumping sites.


2021 ◽  
Vol 8 (1) ◽  
pp. 1-5
Author(s):  
Nahla S El-Shenawy ◽  
Heba N Gad EL-Hak ◽  
Mahi A Ghobashy ◽  
Maha FM Soliman ◽  
Farida A Mansour ◽  
...  

Accumulation of heavy metals in fish is considered a critical problem for human health. Therefore, the study aimed to quantify the concentrations of iron (Fe), zinc (Zn), manganese (Mn), and lead (Pb) in Oreochromis niloticus and Clarias gariepinus from two areas in Al Sharqia governorate, Egypt, from September 2017 to August 2018. A human health risk assessment was conducted to evaluate the potential hazards associated with fish consumption. Metals concentrations (mg/kg dry weight) in muscles of catfish ranged 1.88-221.26 for Fe; 1.78-19.77 for Zn; BDL-238.51 for Mn; BDL-22.75 for Pb. In muscles of tilapia fish metals concentrations ranged 7.96-149.10 for Fe; 1.20-19.77 for Zn; BDL-230.82 for Mn; BDL-25.93 for Pb. Pb had Hazard quotients (HQs) which indicated potential health risks to tilapia consumers at both study areas and catfish consumers at the Faqous area. Fishermen were at higher risk compared to the other consumers.


2018 ◽  
Vol 69 (11) ◽  
pp. 1712
Author(s):  
L. Marszał ◽  
M. Grzybkowska ◽  
D. Błońska ◽  
J. Leszczyńska ◽  
M. Przybylski

The feeding habits of spirlin Alburnoides bipunctatus were investigated in a tributary of the River Vistula (Poland). To evaluate size-related patterns of resource use, fish were assigned to three size classes, defined according to size at first maturation: small (29–70-mm total length, TL), medium (71–90mm TL) and large (91–104mm TL). There was a significant ontogenetic shift in the feeding pattern among size classes, marked by differences in the proportion of the main taxonomic groups of prey consumed: small spirlin primarily consumed chironomid larvae, whereas medium and large spirlin showed a preference for Coleoptera, Ephemeroptera and imagines of unidentified insects. The proportion of prey taken from the water column was significantly lower for small- than medium- and large-sized spirlin. This difference was attributed to the benthic habits of small spirlin compared with medium and large spirlin. The shift to open water feeding in spirlin corresponded with sexual maturation, with habitat segregation between the smallest size class (comprising juveniles) and larger size classes (mature individuals). Size-specific changes in the diet composition of this species have not previously been documented.


2002 ◽  
Vol 82 (4) ◽  
pp. 433-438 ◽  
Author(s):  
M T Morera ◽  
J. Echeverría ◽  
J. Garrido

The recycling of sewage sludge to agricultural land results in the slow accumulation of potentially toxic heavy metals in soils. A greenhouse experiment was conducted to determine the bioavailability of Cu, Ni, Pb and Zn applied to soils in urban anaerobically stabilized sewage sludge. The soils were Lithic Haplumbrept (Lh), Calcixerollic Xerochrept (Cx1 and Cx2) and Paralithic Xerorthent (Px). Sunflower plants (Helianthus annuus L) were grown in the soils following amendment with the sludge. The addition of sewage sludge markedly increased the average dry weight of the plants in the soils that had lower yields without sludge addition (Lh, Cx2, and Px). The acid pH of the Lh soil favoured the bioavailability of Zn from sewage sludge. The bioavailability of Cu was greater in the alkaline soils than in the acidic soil (Lh), which can be attributed to the high organic matter content of the Lh soil which complexes Cu and impairs its uptake by the plants. The concentration of metals in the plants increased with the sewage sludge dose. The effect of the soil type on the metal concentration in plants was greater that the effect of the dose. Key words: Soils, sewage sludge, heavy metals, bioavailability, sunflower


1989 ◽  
Vol 145 ◽  
Author(s):  
W. S. Hobson ◽  
S. J. Pearton ◽  
V. Swaminathan ◽  
A. S. Jordan ◽  
Y. J. Kao ◽  
...  

AbstractThe electrical and photoluminescent properties of vanadium incorporated into GaAs epitaxial layers from a VO(OC2 H5)3 source during organometallic vapor phase epitaxy were examined. The vanadium concentration in the GaAs was controllably varied from 1016 to 1018 atoms cm−3. Deep level transient spectroscopy showed the presence of an electron trap at Ec – 0.15 eV which increased in concentration with vanadium content of the epitaxial layers. A maximum value of 8 × 1015 cm−3 for this trap was obtained. There were no midgap electron traps associated with vanadium. In intentionally Si-doped epitaxial layers, co-doping with vanadium was observed to have no effect in reducing the carrier density when the Si concentration was > 4 × 1016 cm−3. The net carrier concentration profiles resulting from 29 si implantation into GaAs containing 1018 cm−3of total V had sharper tails than for similar implantation into undoped material, indicating the presence of less than 1016 cm−3V-related acceptors. Photoluminescent spectra exhibited the characteristic V+3intracenter emission at 0.65∼0.75 eV. No other deep level photoluminescence was detected. For a V concentration of 1016 cm−3only 2.5 × 1013 cm−3was electrically active. Over the entire V concentration investigated this impurity was predominantly (≥99%) inactive.


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