نوع مقاله : مروری
نویسندگان
1 بخش تحقیقات فیزیک و شیمی خاک و فناوری کود، موسسه تحقیقات خاک و آب کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج ایران
2 بخش تحقیقات شیمی و فیزیک خاک و فناوری کود، موسسه تحقیقات خاک و آب، سازمان تحقیقات آموزش و ترویج کشاورزی، کرج، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Population growth and lifestyle changes have turned waste production into a global challenge. Composting serves as a solution for organic waste management, but heavy metals in compost may threaten both the environment and human health. This study aimed to develop a scientific methodology for determining permissible limits of heavy metals in municipal waste compost for agricultural use in Iran. The research identified two primary approaches for setting limits: adopting foreign standards or developing localized standards. Given significant variations in waste composition, production methods, and national regulations across countries, directly applying foreign standards without local adaptation lacks scientific validity. This paper proposes the "elemental balance method" as the most suitable approach for Iran. In this method, permissible limits for each element are calculated based on: 1) maximum allowable soil concentration after 45 years of continuous use, and 2) an application rate of 25 tons per hectare annually. The proposed limits (mg/kg dry weight) for heavy metals in Iranian municipal compost are: Arsenic: 5, Cadmium: 10, Chromium: 150, Lead: 100, Nickel: 120, Cobalt: 25, Copper: 650, Zinc: 1300, Molybdenum: 5, and Mercury: 5. Findings highlight the need to revise current standards for chromium and nickel in Iranian soils due to their naturally high background concentrations. The study emphasizes the importance of integrated compost management - from production to application - with continuous monitoring to ensure environmental safety. Implementing these science-based, locally-adapted standards while maintaining proper application rates can enable safe agricultural use of municipal compost while protecting soil health and food safety.
کلیدواژهها [English]
)