Characteristics of mineralogical composition and heavy metals in vegetable cultivation land in the Van Noi - Tien Duong (Dong Anh) and Dai Thinh (Me Linh) areas, Ha Noi city

The green vegetable belt for Hanoi city extended in Thanh Tri, Gia Lam, Dong Anh and Me Linh districts, is providing daily thousands of tons of green vegetables for the city. Previously there were some studies on the distribution of heavy metals in the suburbs of Hanoi, including in the Dong Anh area, but the results were limited. Thus the study of material composition and heavy metal distribution in vegetable lands in the Van Noi - Tien Duong area (Dong Anh) (one of the critical vegetable growing areas in the suburbs of Hanoi) and Dai Thinh area (Me Linh) has been selected to contribute to the scientific basis for the production of safe vegetables for the study area. The authors used traditional research methods (Field trip investigation) and modern methods (X-Ray, ICP-EOS and AAS) to show that the soil developed in these areas is rich in quartz. The soil, therefore, has relatively good ventilation and drainage but still ensures the necessary moisture for plants, suitable for the cultivation of short-term vegetables. At the time of the study, vegetable cultivation land in Tien Duong - Dong Anh and Dai Thinh - Me Linh has generally not been polluted by most the heavy metals, excepting the signs of Pb, Cu pollution at a deficient level in some sites. In addition, vegetable cultivation land in Van Noi - Dong Anh has been polluted with typical heavy metals, such as arsenic (As) and lead (Pb). Measures are needed to minimize and progressively eliminate pollution to ensure safe vegetable production.