نشریه محیط زیست طبیعی

پایش غلظت سرب، نیترات و نیتریت در شیر خام، مطالعه موردی: دامداری‌های منطقة لنجان (استان اصفهان)

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانش آموخته کارشناسی ارشد آلودگی محیط زیست، دانشکده منابع طبیعی، دانشگاه صنعتی اصفهان، ایران

2 دانشارگروه محیط زیست، دانشکده منابع طبیعی، دانشگاه صنعتی اصفهان، اصفهان، ایران

3 استادیار گروه محیط زیست، دانشکده منابع طبیعی، دانشگاه صنعتی اصفهان، اصفهان، ایران

4 استاد، گروه صنابع غذایی، دانشکده کشاورزی، دانشگاه صنعتی اصفهان، اصفهان، ایران

چکیده

شیر و فرآورده‌های آن به دلیل ارزش غذایی بالا و مصرف در سنین مختلف، بخش مهمی از رژیم غذایی انسان را تشکیل می‌دهد. آلودگی شیر به نیترات و فلزات سنگین یک خطر مهم برای انسان تلقی می‌شود که در دوران کودکی بسیار شایع‌تر است. شهرستان لنجان در جنوب غربی استان اصفهان قرار دارد و صنایع مختلفی از جمله ذوب‌آهن اصفهان و فولاد مبارکه در اطراف این شهرستان استقرار یافته‌اند. همچنین به دلیل فعالیت‌های کشاورزی در این منطقه، محصولات لبنی از جمله شیرخام می‌توانند در معرض آلودگی به فلزات سنگین و نیترات قرار گیرند. هدف از این مطالعه، بررسی غلظت سرب، نیترات و نیتریت در شیر خام دامداری­های منطقه لنجان است. نمونه‌برداری از شیر خام در ظروف پلی‌اتیلنی از 30 واحد گاوداری شامل واحدهای صنعتی، نیمه‌صنعتی و سنتی مستقر در مناطق مختلف شهرستان انجام گرفت. همچنین 8 نمونه شیر خام و پاستوریزه از یک شرکت فرآوری محصولات لبنی منطقه در چهار روز مختلف کاری جمع‌آوری شد. نتایج نشان داد محدوده غلظت نیترات 12/6-0 با میانگین 1/41 میلی‌گرم بر کیلوگرم، نیتریت 3/3-0 با میانگین 0/11 میلی‌گرم بر کیلوگرم و سرب 0/387-0/006با میانگین 0/03 میلی‌گرم بر کیلوگرم بود. غلظت نیترات و نیتریت نمونه‌ها کمتر از استاندارد کدکس (به ترتیب 10 و 1 میلی‌گرم بر کیلوگرم) بود. همچنین مقدا ر سرب در 7/16 درصد نمونه‌ها بیشتر از استاندارد جهانی (0/02 میلی‌گرم بر کیلوگرم) به‌دست آمد. ارزیابی ریسک سرب و نیترات برای انسان‌ از طریق مصرف شیر خام در محدودۀ ایمن بود. ضریب خطر (THQ) برای سرب 0/14، نیترات و نیتریت به ترتیب 0/01 و صفر بود. با این وجود، پایش آلاینده‌های مختلف در محصولات لبنی در مناطقی که با خطر افزایش آلودگی مواجه هستند، ضروری به نظر می‌رسد.

کلیدواژه‌ها

عنوان مقاله [English]

Monitoring of lead, nitrate, and nitrite concentrations in the raw milk; a case of study (livestock of the Lenjan region, Isfahan Province)

نویسندگان [English]

  • Bahare Aliaskari 1
  • Nourollah Mirghaffari 2
  • Mohammad Nemati Varnosfaderany 3
  • Mehdi Kadivar 4

1 M.Sc. Graduated, Environmental Department, Faculty of Natural Resources, Isfahan University of Technology, Isfahan, Iran

2 Associate Professor, Environmental Department, Faculty of Natural Resources, Isfahan University of Technology, Isfahan, Iran

3 Assistant Professor, Environmental Department, Faculty of Natural Resources, Isfahan University of Technology, Isfahan, Iran

4 Professor, Department of Food Science, College of Agriculture, Isfahan University of Technology, Isfahan, Iran

چکیده [English]

Milk and dairy products, due to their high nutritional value and consumption by all ages, are an important part of the human diet in many parts of the world. Nitrate and heavy metals contamination of milk is a danger to humans that is much more common in childhood. The Lenjan county in the southwest of Isfahan province and different industries, such as Esfahan Steel Company and Mobarakeh Steel Company, are located around the region. In addition, because of the intensive agricultural activities in this region, dairy products, including raw milk, could be exposed to nitrate and heavy metals pollution. The objective of this study is to investigate the concentration of lead, nitrate, and nitrite in the raw milk of livestock in the Lenjan region. Raw milk sampling was performed in polyethylene containers from 30 farms including industrial, semi-industrial, and traditional units situated in the different parts of the county. Furthermore, eight samples of raw and pasteurized milk from a dairy processing company in the region were collected in four different working days. The vanadium trichloride reduction and graphite furnace atomic absorption methods were used to measure the nitrate and lead concentrations of the samples, respectively. The results demonstrated that the concentration range of nitrate was 0-12.6 with a mean of 1.41 mg/kg; nitrite was 0-3.3 with a mean of 0.11 mg/kg; and lead was 0.006-0.387 with a mean of 0.03 mg/kg. Nitrite and nitrate levels of the samples were less than the standard of Codex (1 and 10 mg/kg, respectively). Moreover, the amount of lead in 16.7% of the samples was higher than the world standard (0.002 mg/kg). The risk assessment of lead and nitrate for humans through the consumption of raw milk was in the safety range. Risk factors (THQ) for lead, nitrate, and nitrite were 0.14, 0.01, and 0.0, respectively. However, monitoring of various contaminants in dairy products in the areas, which are at high risk of contamination, seems to be necessary.

کلیدواژه‌ها [English]

  • Risk assessment
  • Lead
  • Raw milk
  • Lenjan county
  • Nitrate
Bahadoran, Z., Mirmiran, P., Jeddi, S., Azizi, F., Ghasemi, A., & Hadaegh, F. 2016. Nitrate and nitrite content of vegetables, fruits, grains, legumes, dairy products, meats and processed meats. Journal of Food Composition and Analysis (51), 93-105.
Bonyadian, M., Moshtaghi, H., & Soltany, Z. 2006. Study on the residual of lead and cadmium in raw and pasteurized milks in Shahrekord area. Iranian Veterinary Journal 2(2), 39-47. (In Persian)
Buket, E.R., Aysel, B.O., Gulderen, Y., 2008. The determination of nitrate and nitrite levels in Turkish white cheese samples consumed in Ankara Region. Gida Derisi 33(4), 153-157.
Codex Alimentarius Commission. 2007. Evaluation of certain food additives and contaminants. Report of the joint FAO/WHO Expert committee on Food Aditives. Geneva, Switzerland 120-90.
Gapper, L.W., Fong, B.Y., Otter, D.E., Indyk, H.E., Woollard, D.C., 2004. Determination of nitrite and nitrate in dairy products by ion exchange LC with spectrophotometric detection. International Dairy Journal 14(10), 881-887.
Gholamzadeh Sarab, M., Pourkhabbaz, A., Hasanpour, M., 2016. Nutritional risk assessment of cadmium, chromium and lead metals due to consumption of Shir-mahi (Scomberomorus commerson) of Sharak River, Quchan. Second National Conference on Conservation of Natural Resources and Environment. University of Mohaghegh Ardabili. (In Persian)
ISIRI 9441.1st. Revision. Milk and milk products determination of zinc content: flame atomic absorption spectrometric method. Institute of Standards and Industrial Research of Iran. ICS 67.100.01. (In Persian)
ISO 6733. IDF/RM 133:2006. Milk and milk products determination of lead content Graphite furnace atomic absorption spectrometric method. This standard was last reviewed and confirmed in 2018. (In Persian)
Javadi, I. Haghighi, B., Abdolahi, A., Nejat, H., 2005. Evaluation and Determination of Toxic Metals (Mercury, Lead, Cadmium, and Chromium) in Cow Milk. Research Journal of Isfahan University 22(2), 57-70. (In Persian)
Khorashadi Zadeh, M.A., 2017. The amounts of heavy metals (lead, cadmium, mercury, nickel, arsenic and chromium) in milk and tissues of Holstein dairy cows in Mashhad. PhD Thesis. Ferdowsi University of Mashhad Faculty of Agriculture 1-107. (In Persian)
Mohamed, T.H., 2011. The occurrence of Nitrate in milk and some dairy product. Journal of Agricultural Science 42(2), 106-116.
Qin, L.Q, Wang, X.P, Li, W., Tong, X. & Tong, W.J. 2009. The minerals and Heavy metals in cow’s milk from China and Japan. Journal of Health Science 55(2), 300-305.
Rahimi, E., Derakhshesh, S.M., 2010. Investigation of Cadmium level in cow's raw milk from different regions of Iran. Journal of Veterinary Medicine & Laboratory 2, 65-73. (In Persian)
Sobhan Ardakani, S., Tizhosh, M., 2016. Determination of Zn, Pb, Cd and Cu contents in raw milk from Khorram-Abad dairies. Journal of Food Hygiene 6(22), 43-88.
Sobhan Ardakani, S., 2018. Human health risk assessment of Cd, Cu, Pb, and Zn through consumption of raw and pasteurized cow’s milk. Iran Journal of Public Health 47(8), 1172-1180.
Safaei, P. , Mohajer, A., 2020. Determination of essential nutrients and heavy metal content of raw cows milk from East Azarbaijan province, Iran. International Journal of Environmental Analytical Chemistry 1-11.
Tajkarimi, M., Poursoltani, H., Ahmadi Faghih, M., Nejad, A.S., 2008. Lead residue levels in raw milk from different regions of Iran. Food Control 1 (5), 495-498.
Watson, D., 2001. Food Chemical Safety, Contaminants, Woodhead Publishing, Elsevier, pp: 322.
Woollard, D.C., Indyk, H.E., 2014. Colorimetric determination of nitrate and nitrite in milk and milk powders use of vanadium reduction. International Dairy Journal 35, 88-94.
 
نشریه محیط زیست طبیعی
دوره 74، شماره 4
اسفند 1400
صفحه 663-676