scholarly journals Cost-effective Method of Analysis for the Determination of Cadmium, Copper, Nickel and Zinc in Cocoa Beans and Chocolates

2014 ◽  
Vol 4 (1) ◽  
pp. 193 ◽  
Author(s):  
Gideon Ramtahal ◽  
Ivan Chang Yen ◽  
Isaac Bekele ◽  
Frances Bekele ◽  
Lawrence Wilson ◽  
...  

<p>The determination of heavy metals in cocoa beans and chocolates is of great importance, due to increasingly stringent regulations being implemented by international legislative bodies and chocolate manufacturers, to protect the health of their consumers. While various techniques exist for heavy metal analyses in cocoa, this study developed a cost-effective, accurate and precise method capable of processing up to 120 samples per batch for the determination of cadmium, copper, nickel and zinc. For sample extractions, a normal laboratory hot plate and locally fabricated high-capacity digestion blocks were used, instead of dedicated block digestion or microwave digestion systems. In addition, only concentrated nitric acid was used, instead of mixed reagents used in standardized methods, for metal extractions from samples, with a sample: extractant ratio of 0.5 g : 10 mL, digestion at 130 ºC, followed by filtration and analysis by flame atomic absorption spectrophotometry. The method was validated with Certified Reference Materials, with heavy metal recoveries generally &gt;95%. Additionally, an in-house quality control sample of ground cocoa nib analyzed together with the Certified Reference Materials was used to monitor the consistency of analyses of heavy metals in cocoa bean samples.</p>

1992 ◽  
Vol 02 (04) ◽  
pp. 489-491 ◽  
Author(s):  
MOMOKO CHIBA ◽  
VENKATESH G. IYENGAR

Tin (Sn) is one of the causative elements of the environmental pollution. As no certified reference materials for Sn are presently available, existing reference materials were analyzed for Sn by two independent analytical techniques; atomic absorption spectrometry (AAS) and neutron activation analysis (NAA). The results obtained by both methods were in agreement except for mixed diet which contains Sn in the range of 50 μ g/g. Further, tin concentrations in human and animal organs have been examined by AAS. Among organs tested tin concentrations in testes were the highest, 2.08±0.62 μ g/g dry weight (mean ±SD, n=12) in humans, and 1.45±0.55 μ g/g (n=8) in mice.


Author(s):  
Mojtaba Arjomandi ◽  
*Hamid Shirkhanloo

Heavy metals are vital and necessary in our daily lives. Moreover, if the amounts of heavy metals are more than the acceptable amounts (mentioned by WHO) in soil, water, and air, indeed, they cause a lot of diseases in human bodies. Therefore, monitoring and measuring the amounts of heavy metals that are arduous and difficult are so important. In this review paper, a lot of studies that have been carried out on the determination and quantification of heavy metals in human bodies, soil, and water are considered. Moreover, the effect of toxicity of each heavy metal on human health is assessed. According to WHO, EPA, NIOSH, ACGIH, and clinical chemistry, the determination of heavy metals such as Cd, Pb, Zn, Hg, Cu, Mn is very important in the human body and Environmental matrixes. 


1987 ◽  
Vol 26 ◽  
pp. 51-58
Author(s):  
Horas Hutagalung ◽  
Suwirma Syamsu

Determination of  heavy  metal  content  (Hg, Pb, Cd, Cu, Cr, Zn) in some seafoods collected from  Muara  Angke  Fish  Auction  Place  were carried out during February to July 1979. The results showed  that Zn  content  in seafoods a nalyzed  was always much higher than the other heavy metals. The concentration levels of  the  six  heavy  metals observed were low. It is almost of the same level as the metal concentration of  other  seafoods  observed  in various parts of the world oceans, but still lower  than the maximum standard set  for human  consumption  as  established  by   Tasmania, Australia and  World Health Organization. The  mean  per capita  consumption of  fish  in Jakarta is only  about 165 g  per week, while  the  Provisional Tolerated Weekly Intake for Hg, set by WHO/FAO at 300 ug level, would be attained by consuming 1500 g Rastrelliger sp., or 698 gPenaeus setiferus, or 545 g Sepia sp., and or 1250 g Pecten sp.  Therefore,  at   present the  level of metal content in fishes sold at TPI  Muara  Angke  can be  considered  as  not  dangerous  to human health as long as these quantities are not surpassed.


2013 ◽  
Vol 88 (4) ◽  
pp. 411-416 ◽  
Author(s):  
O.M.S. Mostafa ◽  
A.-T.H. Mossa ◽  
H.M.A. El Einin

AbstractIn spite of using aquatic snails as bioindicators for water pollution, little attention has been paid to the effect of parasitism upon the concentration of heavy metals (Al, Cd, Cu, Fe, Mn, Pb and Zn) in these organisms. The present study therefore aimed to compare the concentrations of heavy metals in trematode-infected Biomphalaria alexandrina collected from Kafer Alsheikh and Menofia provinces, Egypt, with uninfected snails from the same sites, in order to assess the effect of parasitism on the use of these snails as bioindicators. The concentrations of heavy metals in the soft parts and shells of snails were measured by flame atomic absorption spectrometry. The results showed that the heavy metal profile in snails infected with Echinostoma liei was very different from that in snails infected with Schistosoma mansoni. The total concentration of heavy metals in E. liei-infected snails collected from Kafer Alsheikh or Menofia province was greater than in uninfected snails. In contrast, the total concentration of heavy metals in S. mansoni-infected snails was reduced compared with uninfected snails. In conclusion, the status of snails with respect to parasitic infection must be taken into consideration when these snails are used as bioindicators.


Sign in / Sign up

Export Citation Format

Share Document