نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی دکتری شیمی و حاصلخیزی خاک دانشگاه تربیت مدرس

2 استاد بازنشسته دانشگاه تربیت مدرس

3 استاد دانشگاه صنعتی اصفهان

چکیده

نیترات (NO3-) به عنوان یک منبع غذایی برای رشد گیاهان ضروری است اما مقادیر زیاد آن در رژیم غذایی انسان با امکان ابتلا به بیماری­های جدی مانند سرطان­های گوارشی و متهموگلوبینمیا در نوزادان در ارتباط است. سبزیجات منبع اصلی نیترات هستند به­طوری­که 80 درصد متوسط جذب روزانه نیترات را تشکیل می­دهند و یکی از دلایل اصلی وجود نیترات مازاد در سبزیجات، مصرف بیش از اندازه کودهای نیتروژنی و استمرار در مصرف نامتعادل کودهای شیمیایی نیتروژن است. با توجه به نگرانی­های جدی درباره امکان آلودگی محصولات کشاورزی مختلف به نیترات، این مطالعه با هدف بررسی انباشتگی نیترات در اندام خوراکی تعدادی از محصولات کشاورزی غالب شهرستان­های استان اصفهان و مقایسه آن با حد بحرانی غلظت نیترات در این محصولات انجام شد. محصولات کشاورزی غالب استان شامل سیب­زمینی (Solanum tuberosum) محصول پرمصرف غذایی و خیار (Cucumis sativus) محصول پرمصرف خام­خواری که در فصل سرد سال امکان انباشتگی نیترات محتمل­تر است، از گلخانه­ها و مزارع کشاورزان پیشرو جمع­آوری شد. سپس نمونه مرکب تهیه و غلظت نیترات نمونه­ها با استفاده از روش دی­آزو تعیین شد. براساس سرانه مصرف این محصولات توسط ساکنین استان اصفهان، نقشه پهنه­بندی خطرپذیری نیترات برای گروه سنی کودکان و بزرگسالان ترسیم شد. نتایج نشان داد میانگین غلظت نیترات در خیار و سیب­زمینی در تمام شهرستان­های مورد بررسی کم­تر از حد مجاز نیترات بود. نقشه­های پهنه­بندی خطرپذیری نیترات در استان اصفهان نشان داد که در تمام مناطق این نسبت کمتر از 1 (بیشینه 051/0 و 02/0 به­ترتیب برای سیب­زمینی و خیار) بود، لذا از لحاظ نیترات اندام­های خوراکی کیفیت سلامت محصولات کشاورزی مورد مطالعه در شرایط مطلوب قرار داشت. با این حال پایش مستمر محصولات کشاورزی جهت اطمینان از کیفیت سلامت آن ضروری است.

کلیدواژه‌ها

عنوان مقاله [English]

Investigation of Nitrate Risk Assessment in Edible Parts of Some Crops Grown in Isfahan Province

نویسندگان [English]

  • Shirin Haftbaradaran 1
  • Mohammad Jafar Malakouti 2
  • Amir Hossein Khoshgoftarmanesh 3

1 PhD Student of Soil Chemistry and Fertility

2 Emeritus professor of Tarbiat Modares University

3 Professor of Isfahan University of Technology

چکیده [English]

Nitrate (NO3) is an essential nutrient for growth of plants, but high concentration of nitrate in human diet increases risk of serious illnesses such as gastric cancer and infantile methemoglobinemia. Vegetables constitute the major source of nitrate, providing 80% of the average daily human dietary intake. Unbalanced fertilization and overuse of nitrogen-based fertilizers are the main reasons for excess accumulation of nitrate in vegetables.In regard with the recent concerns about contamination of vegetables to nitrate, the present study was conducted to compare nitrate accumulation in edible parts of some predominant crops in Isfahan province in comparision with critical level of nitrate in vegetables.Predominant crops grown in Isfahan including potato (Solanumtuberosum) which is basic vegetable in human diet and cucumber (Cucumissativus) which is basic raw-used vegetable were sampled in cold season (mid-October until end-November), with high probability of nitrate accumulation, from pioneer greenhouses and farms. Nitrate concentration in edible parts of compound sampled plants were measured by diazo method. Interpolation maps of nitrate hazard quotient for children and adults based on per capita consumption of these crops were drawn. Results showed that mean nitrate concentrations in cucumber and potato samples collected from all cities were below permisible level. According to the results obtained from interpolation maps of nitrate and the fact that in all cities THQ for nitrate was below 1 (Maximum 0.051 and O.2 for potato and cucumber, respectively). Therefore, the health quality of the studied crops in terms of nitrate concentrations was acceptable. Although continuous monitoring of crops is essential.

کلیدواژه‌ها [English]

  • Nitrate accumulation
  • Cucumber (Cucumis sativus)
  • Potato (Solanum tuberosum)
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