tailieunhanh - TOXICOLOGICAL CHEMISTRY AND BIOCHEMISTRY - CHAPTER 11

Trong Chương 10 yếu tố đã được thảo luận như một quy luật có xu hướng độc hại trong các hình thức khác nhau của họ. Chương 11 bao gồm các hợp chất vô cơ độc hại của các yếu tố mà không phải là bản thân thường được coi là chất độc. Những yếu tố này bao gồm hầu hết các phần phi kim nhẹ hơn nằm ở phía trên bên phải của bảng tuần hoàn (hình ) và loại bỏ các kim loại nặng. Hầu hết các yếu tố liên quan đến các hợp chất vô cơ được. | Chapter 11 Toxic Inorganic Compounds introduction In Chapter 10 elements were discussed that as a rule tend to be toxic in their various forms. Chapter 11 covers toxic inorganic compounds of elements that are not themselves generally regarded as toxic. These elements include for the most part the lighter nonmetals located in the upper right of the periodic table Figure and exclude the heavy metals. Most of the elements involved in the inorganic compounds discussed in this chapter are those that are essential for life processes. Any division between toxic and nontoxic elements is by nature artificial in that most of the heavy metals have compounds of relatively low toxicity and there are deadly compounds that contain elements essential for life. Chapter Organization In general this chapter is organized in the order of increasing atomic number of the elements that are covered. Inorganic compounds of carbon atomic number 6 are discussed first followed by toxic inorganic compounds of nitrogen atomic number 7. The next element oxygen occurs in so many different inorganic compounds that it is not discussed in a separate category. The halogens fluorine chlorine bromine and iodine are discussed as a group because of their chemical similarities. The other major elements whose toxic inorganic compounds are discussed are silicon phosphorus and sulfur. toxic inorganic carbon compounds Cyanide Cyanide in the form of either gaseous hydrogen cyanide HCN or cyanide ion CN- present in cyanide salts such as KCN is a notably toxic substance. Cyanide is a rapidly acting poison and the fatal oral dose to humans is believed to be only 60 to 90 mg. Hydrogen cyanide and cyanide salts have numerous uses examples are as ingredients of pest poisons fumigants metal silver polishes and photographic chemical solutions. Therefore exposure to cyanide is certainly possible. Hydrogen cyanide is used as a fumigant to kill pests such as rodents in warehouses grain storage