有些材料太普通了,我们都习以为常了。其中一种材料是一种灰色的金属,已经伴随我们数千年了。这种金属就是铅,它仍然是世界上最有用的物质之一,它在人类社会中一直扮演着重要的角色。铅的原子符号为Pb(在拉丁语中表示铅)。铅的原子序数为82,原子质量为207.19 AMU。它在约327.502 oC时熔化,在1740 oC时沸腾。铅是一种重的、有延展性的、软的灰色固体。它溶于硝酸,不溶于水。它分布在北美、中南美洲、澳大利亚、非洲和欧洲。在现代,铅有了广泛的用途,世界对铅及其产品的需求稳步增长。 Lead’s usefulness stems from the metal’s many desirable properties: softness, high density, low melting point, ability to block radiation, resistance to corrosion, readiness to form alloys and chemical compounds, and ease of recycling. Its versatility, as well as its physical and chemical properties, accounted for its extensive use. Lead can be rolled into sheets which can be made into rods and pipes. It can also be molded into containers and mixed with other metallic elements.

铅在古代被用来制造钱币、艺术品和水管。铅是最早被发现的有毒物质之一罗马人用它来衬砌沟渠和在用于储存食物和葡萄酒的容器上釉;人们怀疑这导致了大面积的铅中毒。19世纪40年代中期,著名的富兰克林西北航道探险队(Franklin Expedition to the Northwest Passage)的成员也遭遇了类似的命运,他们被焊料中的铅毒死,当时焊料被广泛用于密封用来储存食物的罐头。直到最近,最重要的用途之一是在汽油中添加抗爆添加剂。在20世纪70年代和80年代,人们采取措施减少含铅气体的使用。到1990年,这些行动实际上已经消除了汽油中铅的使用。铅也是回收利用的最好和最早的例子之一,在加拿大,大约55%的铅来自回收材料。有毒侵权行为的一个特殊类别是由于接触含铅油漆造成的伤害。含铅油漆的危害早在20世纪初就已为人所知,当时澳大利亚禁止在油漆生产中使用铅。然而,美国的铅开采和铅颜料工业能够先发制人地阻止在油漆生产中使用铅的禁令,直到1978年,它(最终)在我国成为非法。 Lead poisoning occurs only when too much lead accumulates in the body. Generally, lead poisoning occurs slowly, resulting from the gradual accumulation of lead in the bone and tissue after repeated exposures. However, it is important to note that young children absorb 50% of a lead ingestion, while adults absorb only 10%. The greatest risk of injury from lead poisoning is to children under the age of seven, whose developing bodies and brains are sensitive to even small amounts of lead, which can leave children with subtle but irreversible injury that does not appear until many years after the exposure to lead. The kinds of injuries lead causes in children include: learning disabilities, brain damage, loss of IQ points and intellect, academic failure, neuropsychological deficits, attention deficit disorder, hyperactive behavior, antisocial (criminal) behavior, neurological problems, encephalopathy (brain swelling), major organ failure, coma, and death. These injuries can be life-threatening or can prevent a child from realizing his or her scholastic, vocational, and financial potential, or from becoming a self-sufficient adult. To confirm lead poisoning, the best test is a venous blood lead level. If the blood lead level is below 25 g/dL, then a serum ferritin level and other iron studies can be used to determine if iron deficiency anemia exists. With an elevated blood lead level of 50 ug/dL, the conclusion is that the boy is lead-poisoned. In this case, the child should be referred for appropriate chelation therapy immediately.

有毒侵权行为的一个特殊类别是由于接触含铅油漆造成的伤害。含铅油漆的危害早在20世纪初就已为人所知,当时澳大利亚禁止在油漆生产中使用铅。然而,美国的铅开采和铅颜料工业能够先发制人地阻止在油漆生产中使用铅的禁令,直到1978年,它(最终)在我国成为非法。铅中毒只有当过多的铅在体内积聚时才会发生。一般来说,铅中毒是缓慢发生的,是由于铅在骨骼和组织中反复暴露后逐渐积累造成的。然而,值得注意的是,幼儿吸收50%的铅摄入量,而成人仅吸收10%。我们可以做什么来防止铅中毒:不要燃烧铅屑。2.将铅碎片放入6毫米的塑料袋中。 3. For storage (of less than 48 hours), place storage bags in a secure area, away from children and animals. 4. Lead materials and debris must be transported in a covered vehicle to a lined municipal landfill in accordance to state regulations.

引用这篇文章如下:威廉·安德森(学校工作助手编辑团队),《领导与环境:危险》,在SchoolWorkHelper, 2019,//www.chadjarvis.com/lead-and-the-environment-dangers/

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