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Potential hazards of toxic metals found in toothpastes commonly used in Nigeria

100%

Orisakwe O. E., Okolo K. O., Igweze Z. N., Ajaezi G. C., Udowelle N. A.

Roczniki Państwowego Zakładu Higieny

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2016

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tom 67

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nr 2

Background. Toothpastes have multi-functional configurations as oral care products. They can however constitute a possible source, amongst others, of toxic metal exposure in public health. Indeed, the public health impact of personal hygiene and consumer products is largely unknown. Objective. To determine the level of toxic metals (lead, cadmium, cobalt, chromium, nickel) in toothpastes available in Nigeria, (home produced and imported), and assess the potential risk to the people. Material and Method. The samples of toothpastes commonly used in Nigeria were tested. Using a market basket protocol thirty five different brands of toothpaste were used. Samples were digest by addition of 10 mL mixture of conc. nitric and hydrochloric acids (HCl:HNO3, 3:1), followed by heating to dryness. 20 mL deionized water was added, stirred and filtered. The filtrate was made up in standard volumetric flask and lead, cadmium, chromium, cobalt and nickel concentrations were determined using the atomic absorption spectrophotometry 205A. The daily intake of metals and target hazard quotient (THQ) were then calculated. Results. Pepsodent and Flodent had the highest levels of lead at respectively 23.575 and 18.092 mg/kg while Colgate Herbal had the highest nickel of 18.535 mg/kg. The daily intake estimates of all imported toothpaste samples were below the stated upper limits (UL). All target hazard quotients were also found to be below one. Conclusions. Although the UL, THQ and daily intake rates were all normal, the high levels of lead in some of the toothpastes an important concern to public health suggesting that pre-marketing safety studies of toothpastes may be worthwhile for the regulatory authorities.

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Mercury fluxes through the sediment water interface and bioavailability of mercury in Southern Baltic Sea sediments

100%

Beldowski J., Miotk M., Pempkowiak J.

Oceanologia

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2009

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tom 51

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nr 2

263-285

Sediment cores collected in several areas of the southern Baltic were analysed for total mercury (HgTOT) and five operationally defined mercury fractions: HgA – contained in pore waters, HgF – bound to fulvic acids, HgH – bound to humic acids, HgS – bound to sulphide, and HgR – residual. An effort was made to quantify mercury fluxes at the sediment/water interface in the study area. Net mercury input, calculated on the basis of sedimentation rate and concentration in the uppermost sediments, ranged from 1 to 5.5 ng cm−2 year−1. Mercury remobilisation from sediments due to diffusion and resuspension was calculated from the proportion of labile mercury and the velocity of near-bottom currents. The results showed that the return soluble and particulate fluxes of mercury from the sediments to the water column constitute a substantial proportion of the input (20–50%), and are slightly higher than those found in pristine areas, although they are less than the values recorded in areas with a history of mercury contamination. In addition, an index was developed to assess the methylation potential of mercury in sediments. Mercury contained in pore waters, and mercury bound to fulvic and humic acids together with Loss on Ignition were used to calculate the semiquantitative methylation potential (Pm). Despite the simplicity of this approach, Pm correlates well with methyl mercury in fish from the study area.

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Toxic heavy metals in the Mahul Creek water of Mumbai, India

100%

Singare P. U., Ansari M. V. A., Dixit N. N.

International Letters of Natural Sciences

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2014

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tom 10

The present study was performed for the period of one year from January 2013 to December 2013 in order to understand the level of toxic heavy metals in the water of Mahul Creek near Mumbai. It was observed that the annual average concentration of heavy metals like Cd, As, Hg, Cr, Pb, Cu, Ni and Zn, was found to be 0.003, 0.004, 0.0009, 0.012, 0.015, 0.019, 0.04 and 0.23 ppm respectively. The results suggest that there is a need to have such scientific monitoring for longer time period in order to understand the trend in level of these toxic heavy metals discharged in to the creek water. It is feared that the existing problem if ignored may increase the level of this heavy metals in creek water thereby creating threat to the biological life of an aquatic ecosystem. From the results of the present investigation it seems that the time has come to move towards ecosystem specific discharge standards to maintain the health and productivity of natural resources on which the majority of Indians are dependent.

4

Impact of soil acidification on heavy metal concentrations in the soil solution

100%

Csillag J., Lukacs A., Bujtas K., Nemeth T.

Zeszyty Problemowe Postępów Nauk Rolniczych

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1998

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tom 456

5

Toxic heavy metals in sediments of Mahul Creek near Mumbai, India

100%

Singare P. U., Ansari M. V. A., Dixit N. N.

International Letters of Natural Sciences

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2014

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tom 10

The present study was performed for the period of one year from January 2013 to December 2013 in order to understand the level of toxic heavy metals in the sediments of Mahul Creek near Mumbai. The annual average concentration of heavy metals like Cr, Zn, Cu, Ni, Pb, Cd, As and Hg was found to be 277.5, 121.7, 100.3, 63.8, 21.5, 14.6, 10.4 and 4.9 ppm respectively. It is feared that this heavy metals accumulated in the creek sediments may enter the water thereby creating threat to the biological life of an aquatic ecosystem. The results of present study indicates that the existing situation if mishandled can cause irreparable ecological harm in the long term well masked by short term economic prosperity due to extensive industrial growth.

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Effect of cadmium on active principle contents of Matricaria recutita L.

100%

Grejtovsky A., Repcak M., Eliasova A., Markusova K.

Herba Polonica

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2001

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tom 47

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nr 3

Przeprowadzono doświadczenie wazonowe z glebą (Haplic Phaeozem), do której dodawano wzrastające dawki kadmu (0 - 0,3 - 3,0 - 30,0 mg/kg), celem określenia ich wpływu na zawartość wtórnych metabolitów w koszyczkach rumianku (Matricaria recutita L. cv. Novbona). Dodatek kadmu do gleby powodował obniżenie zawartości olejku eterycznego w surowcu (Chamomillae anthodium) średnio o 10%, chamazulenu o 28% i (-)-α-bisabololu o 20%, a także akumulacji flawonu apigeniny i kumaryny herniaryny. Natomiast poziom (E)-β-farnezenu i en-in-dicykloeteru wzrastał w surowcu wraz ze wzrostem zawartości kadmu w glebie. Nie zaobserwowano toksycznego oddziaływania kadmu na rośliny podczas doświadczenia. Ponadto pierwiastek ten nie miał większego wpływu na plon surowca.

7

Toxic metals in bottom sediments and ferromanganese concretion of the Southern Baltic Sea

100%

Szefer P.

Oceanological Studies

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2000

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tom 29

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nr 1

8

Some physiological and biochemical aspects of plant resistance to cadmium effect. I. Antioxidative system

100%

Stroinski A.

Acta Physiologiae Plantarum

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1999

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tom 21

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nr 2

The hitherto studies on the effect of cadmium on plants have shown that it causes intensification of two types of unfavorable processes in plants: inactivation of macromolecules and cellular structures and induction of oxidative stress. In response, the plant organism activates processes restoring its homeostasis, i.e. those which remove reversible and irreversible changes. In removing the former a particular role is played by the antioxidative system containing enzymatic and nonenzymatic antioxidants, and removing the active forms of oxygen. The strategy of stress tolerance plays an important role in the plant resistance to cadmium and other toxic metals.

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The toxic Doppelganger: on the ionic and molecular mimicry of cadmium

84%

Chmielowska-Bak J., Izbianska K., Deckert J.

Acta Biochimica Polonica

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2013

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tom 60

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nr 3

Cadmium is a toxic heavy metal which can cause numerous alterations in cell functioning. Exposure to cadmium leads to generation of reactive oxygen species, disorders in membrane structure and functioning, inhibition of respiration, disturbances in ion homeostasis, perturbations in cell division, and initiation of apoptosis and necrosis. This heavy metal is considered a carcinogen by the Agency for Toxic Substances and Disease Registry. At least some of the described toxic effects could result from the ability of cadmium to mimic other divalent ions and alert signal transduction networks. This review describes the role of cadmium mimicry in its uptake, reactive oxygen species generation, alterations in calmodulin, Wnt/β-catenin and estrogen signaling pathways, and modulation of neurotransmission. The last section is dedicated to the single known case of a favorable function performed by cadmium mimicry: marine diatoms, which live in zinc deficient conditions, utilize cadmium as a cofactor in carbonic anhydrase - so far the only described cadmium enzyme.

10

Soil acidification and the mobilisation of toxic metals caused by acid deposition and fertiliser application

84%

Goulding K. W. T., Blake L.

Zeszyty Problemowe Postępów Nauk Rolniczych

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1998

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tom 456

The Classical and other long-term experiments at Rothamsted Experimental Station illustrate the causes and effects of soil acidification. One hundred and fifty years of precipitation measurements show how atmospheric deposition has increased, causing acidification of grassland and woodland soils. Where applied, ammonium fertilisers cause very rapid acidification unless their effects are offset by the application of lime. Acidification causes the mobilisation and removal by leaching of base cations to be replaced by aluminium, manganese or iron, the reduction of base saturation and, in the long-term, the reduction of cation exchange capacity by the weathering of clay minerals. Mobilised toxic metals are taken up by vegetation growing on the acidified soils. Some plots of the Park Grass Experiment have acidified to sufficiently to cause the release of aluminium to be taken up in hay in amounts toxic to cattle - a Chemical Time Bomb.

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Effect of Mg supplementation on bioelements [Zn and Cu] in kidneys of mice exposed to acute Cd intoxication

84%

Djukic D., Matovic V.

Journal of Elementology

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2005

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tom 10

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nr 4 Suppl.1

26-27

12

Environmental characteristics by eco-sanitary and toxic criteria of the cooling pond of Zaporizhzhya Nuclear Power Plant (Ukraine)

84%

Fedonenko O., Ananieva T., Sharamok T., Marenkov O.

International Letters of Natural Sciences

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2018

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tom 70

It has been investigated the ecological status of the cooling pond of Zaporizhzhya Nuclear Power Plant (NPP) on the hydrochemical and toxicological indicators. The ecological water quality by most hydrochemical and hydrophysical indices corresponds to the class II, category 3, and is characterized as "fairly clean". However, according to the BOD5 index, the water quality is "satisfactory" (class III, category 4). By the contents of both nitrogen of nitrates and phosphorus of phosphates the water quality belongs to the class IV, category 6, as "bad, dirty water". The main anthropogenic pollutants are copper, iron, zinc, and fluorides. The ecological characteristics by their concentrations in the water correspond to the class III, and categories 4–5 of quality, which are "poorly and moderately polluted" water. Accumulation of toxic metals in the surface layer of the reservoir bottom sediments depends on their types, the minimal content is found in sandy sediments, and maximal one is in muddy sediments. The possibility of significant secondary pollution of the water environment by toxic metals is small under the hydrophysical and hydrochemical conditions typical for the cooling pond of Zaporizhzhya NPP. According to the calculations, the value of the average chemical index of ecological quality is "2.5", which characterizes the water of the Zaporizhzhya NPP cooling pond as "good" and "clean".

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Phyto-availability of potentially toxic metals in Curcubita ficifolia grown on contaminated and non-contaminated soils

84%

Enenebeaku C. K., Anyanwu C. N., Okorocha N. J., Enenebeaku U. E., Nzediegwu E., Ogukwe C. E.

International Letters of Natural Sciences

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2016

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tom 59

14

Effect of organic substance in the substrate on the content of cadmium in the edible parts of vegetable crops

84%

Tyksinski W., Bres W., Bosiacki M.

Roczniki Akademii Rolniczej w Poznaniu. Ogrodnictwo

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2002

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tom 35

15

Chromosome and genome mutations caused by toxic metal

84%

Dovgalyuk A., Kalynyak T., Blume Y.

Biological Bulletin of Poznań. Supplement

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1997

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tom 34

16

The interaction of Pb and Ca assimilation in Helix aspersa with wounded shells

84%

Beeby A.

Polish Journal of Environmental Studies

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1993

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tom 02

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nr 3

The interaction of lead and calcium assimilation was examined in the soft tissues, shell and faeces of the soft tissues, shell and faeces of the garden snail an induced calcium stress, shell wounding. This is known to mobilise Ca both from the shell and soft tissues, conditions which are likely to affect Pb assimilation by each component Following wounding, snails were fed an artificial diet for 7 days with some combination of Pb and/or Ca and Mg in a 22 factorial experiment Dietary Pb raised the concentration of this metal in all tissue components, though the scale of the increase was the same in both wounded and unwoun- ded snails. The smallest increase was in the shell. Ca and Mg levels in the hepatopancreas remain unchanged by the dietary levels of any treatment, but were raised in the rest of the soft tissues. Significantly, the high Pb diet is almost equally effective as wounding in lowering the Ca in this component. Injuring the shell had little effect on the uptake of Pb by the snails.

17

Calcium effect on the synthesis of lysine and arginine containing proteins in cortex cells of pea [Pisum sativum L.] root meristem treated with toxic metals

84%

Gabara B., Krajewska M.

Biological Bulletin of Poznań. Supplement

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1996

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tom 33

18

Phytochelatin synthesis in the green alga Stichococcus bacillaris in response to cadmium - influence of environmental factors

84%

Skowronski T., Pirszel J.

Biological Bulletin of Poznań. Supplement

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1996

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tom 33

19

Effect of calcium and toxic metals on RNA synthesis and transport in cortex cells of root meristem of Pisum sativum L.

84%

Gabara B., Krajewska M.

Polish Journal of Environmental Studies

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1997

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tom 06

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nr 3

Experiments with 3H uridine incorporation showed that a 144-hr treatment with cadmium, chromium or lead, each at a concentration of 10-4 M, as well as the addition of calcium (10 -3 M), affected RNA in the nucleolus, nucleoplasm and cytoplasm in cortex cells of pea root meristem. Disturbances in RNA transport (especially from the nucleolus to the cytoplasm) appearing due to toxic metals and calcium suggest that this RNA was mostly of nucleolar origin.

20

A comparative study of lead uptake by three populations of the snail Helix aspersa Muller

84%

Richmond L., Beeby A.

Polish Journal of Environmental Studies

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1992

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tom 01

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nr 1

Pb uptake by three populations of the snail Helix aspersa was measured in a series of experiments supplying PbS04 in an agar diet. Uptake rates in snails from a site grossly polluted with Pb were lower than in the two other populations and were unafected by the initial body burdens of Pb. Populations of snails from a Pb-free site showed much greater variability in tissue Pb burdens and faster rates of accumulation than populations from the polluted site. Snails from a site with Pb concentrations between the other two sites showed intermediate rates of uptake. It is suggested that snails from the highly contaminated site have adapted to high environmental levels of Pb and that this adaptation is genetically based.

Ograniczanie wyników

Potential hazards of toxic metals found in toothpastes commonly used in Nigeria

Mercury fluxes through the sediment water interface and bioavailability of mercury in Southern Baltic Sea sediments

Toxic heavy metals in the Mahul Creek water of Mumbai, India