Copper and Nickel Determination in Grape Extract Cultured around Marvast City,Yazd
Mohammad Hossien Salmani; PhD¹, Neda Shirvani; BSc¹ & Zahra Shekari; BSc<sup>*1

1</sup> Department of Environmental Health, School of Public Health, Shahid Sadoughi University of Medical Sciences,
Yazd, Iran

ARTICLE INFO		ABSTRACT
ORIGINAL ARTICLE		Background: One of the most critical problems in the field of water and food pollution is the heavy metal pollution. Agricultural products are exposed to this type of contamination through wastewater; industrial activity and population pollutions are also in its area. Since the plant in the affected areas can directly enter heavy metals into the food chain, so, it is important to check their level of contamination. The purpose of this study was to monitor distribution of copper and nickel in the grape cultured in the farms around Marvast in Yazd province. Methods: All chemicals were of analytical grade. In order to determine the level of copper and nickel in grape extracts produced from the most important areas in grape production, 7 samples of grape were taken from these geographic regions. After grinding and homogenizing of samples, the concentration of nickel and copper, heavy metals were measured by atomic absorption spectrometer. The obtained results were analyzed through SPSS software based on statistical methods. Results: The mean value of copper and nickel were 26.4 ± 3.1 and 12.3 ± 1.5 μg/kg, respectively. According to the obtained results and their comparison with standards, different amounts of copper and nickel were observed in all samples, however, the highest amount of these metals was observed in one sample. Conclusions: Concentrations of heavy metals in samples from different regions were lower than the maximum allowable concentration of copper and nickel. Although, the amount of these metals in one sample, known as pollution indicator, suggested that this area can be exposed to both.   Keywords: Copper; Nickel; Grape; Marvast city
Article history: Received: 5 Dec 2016 Revised: 30 Dec 2016 Accepted: 5 Jan 2017
*Corresponding Author: School of Public Health, Shahid Sadoughi University of Medical Sciences, Square Alem, Shohadaye Gomname Blvd, Yazd, Iran. Shekari_Zahra@yahoo.com   Postal code: 8915833667 Tel: +98 35 38209100

 

  

Sometimes plants are used as indicators of ecosystem health (Temple et al., 2012). Fruits and vegetables are important part of human diet. Concentration of heavy elements in these crops is then major factors to recognize healthy foods. Plants’ pollution from heavy metals can be caused by effluent fertilizer and pesticides (Atafar et al., 2010, Azenha and Vasconcelos, 2000a). Fruits and vegetables’ growth environment (soil, air, nutrients) is the main source of heavy metals, plants absorb them via their roots or leaves (Alloway, 1990). Plants’ uptake and bioaccumulation of heavy metals depends on factors such as climate, atmospheric sediments, soil, heavy metal concentrations in soil, and their growth nature (Moore and Luoma, 1990). Metals are transported into grape plants via root absorption and accumulate into their different parts including the grain (Golia et al., 2008). Mobility of metal ions and its absorption by plant (from root to leaf) is under the influence of soil and soil pH’s physicochemical properties (Antonious and Kochhar, 2009).
The final consequence of such accumulation is increase of heavy metals in the fruit. Because of Cu (45–98%) and Ni (16–75%) high gastrointestinal absorption, continuous consumption of fruits with elevated concentrations of them causes chronic poisoning, depending on the type of fruit (Azenha and Vasconcelos, 2000b).
Human health has been at risk by consuming more fruits and vegetables contaminated with heavy metals such as Ni and Cu (Angelova et al., 1999). CU is a trace element that is essential for human body and biochemical. High amount of Cu causes kidney damage, hypertension, mutagenicity, and carcinogenicity, while overdoses of Ni cause respiratory system, nerve, and heart damage. The maximum allowable concentration of Cu and Ni in adults’ diet should not exceed 10 and 5 mg per kg, respectively (Nunes et al., 2011). The purpose of this study was to monitor distribution of copper and nickel in the grape cultured in the farms around Marvast in Yazd province.
Materials and Methods
Study design and sampling: This cross-sectional study was carried out in October 2016. 7 samples of grape were collected from all farms of Marvast city of Yazd province in the center of Iran during the fruit production season. In sampling, seedless grapes were taken three times from each region in a month (6 samples per month for 7 region 21 samples).  From each region, about 1 kg of grape was collected, placed in a plastic bag, and transported to the laboratory.
Measurements: To exclude possibility of contamination with trace elements, all glasswares were previously washed with 1% of nitric acid and rinsed with distilled water thoroughly. All chemicals were analytical grade and used without any purification. The Cu²⁺ and Ni²⁺ 100-ml stock solutions were prepared by dissolving appropriate amounts of CuSO₄.5H₂O and Ni(NO₃)₂.6H₂O in distilled water by volumetric flasks. The standard solutions were prepared by diluting its stock solution for each element.
Grape samples were separately washed 3 times, rinsed with distilled water, and crushed in a mill. After grinding and homogenizing, the suspensions were filtrated and centrifuged to obtain a clear solution. The resulting solution was placed into the 105 °C oven for 48 hours to dry completely. One g of each dried sample was weighted by an accurate balance and acid digestion was carried out for each sample according to standard methods. Ni and Cu concentrations were measured 3 times in each sample by atomic absorption spectrometer.
Data analysis: The results were expressed as mean ± SD by using SPSS software (SPSS Inc., Chicago, IL, USA). Differences among groups’ mean scores were determined by independent sample t-test while the significance level was set at P-value < 0.05. For data certification, the analysis of standard solutions provided quality control of the measurements.
Results
The Cu values ranged from 20.6 to 44.1 μg/kg with a mean value of about 26.4 ± 3.1 μg/kg. The Ni values also varied from 10.1 to 21.4 μg/kg with a mean value of 12.3 ± 1.5 μg/kg. The measured elemental concentrations in 3 samples of red grape and 4 samples of white grape as well as their standard errors are presented in Table 1.
The comparison of concentrations of two heavy metals (Cu and Ni) in the studied area are
presented in Figure 1.