在各种微量元素中,有10种必需微量元素对人体营养健康影响较大,它们可分为2类:第4类主要来自膳食,包括Fe,Zn,Cu,Cr;第2类来自地球化学环境,包括F,I,Se,Mo,As,B。在第1类必需微量元素中,Cu,Fe,Zn元素的缺乏或过多以及Cr元素的过多都会引起植物病,这说明地球化学因素也影响此类必需微量元素。此外,该类元素都是金属元素,它们在人体内的吸收率较低,因此人体内易缺乏该类元素,但不易导致中毒。同第1类相比,第2类必需要微量元素入人体后具有较高的吸收率。该类元素中,F,I,Se,Mo这 Of the various trace elements, there are 10 kinds of essential trace elements on human nutrition and health have a greater impact, they can be divided into two categories: the fourth category mainly from the diet, including Fe, Zn, Cu, Cr; the second category from geochemistry Environment, including F, I, Se, Mo, As, B. In the essential trace elements of the first category, the absence or excess of Cu, Fe, Zn and the excess of Cr all cause plant diseases, indicating that geochemical factors also affect such essential trace elements. In addition, these elements are metal elements, their absorption rate in the human body is low, so the body easily lack of such elements, but not easily lead to poisoning. Compared with the first category, the second category must trace elements into the human body has a higher absorption rate. Of these elements, F, I, Se, Mo this