首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Geology and Health The importance of particular metals in the human diet has been realised within the past few decades, and
Geology and Health The importance of particular metals in the human diet has been realised within the past few decades, and
admin
2010-01-14
62
问题
Geology and Health
The importance of particular metals in the human diet has been realised within the past few decades, and the idea that geology might be related to health has been recognized for a number of elements such as iodine, zinc and selenium. For example, soils with low iodine contents produce crops and animals deficient in iodine. A lack of iodine in the human diet leads to some serious diseases.
The ultimate source of metals within the human body is rocks, which weather into soil, gaining or losing some of their chemical constituents. The crops we eat selectively remove from the soil the elements that they require for growth. The water we drink contains trace elements leached from rock and soil. Thus the geology and geochemistry of the environment have effects on the chemistry and health of plants, animals and people.
So far there is no data to suggest that people living on metal-rich soils experience a potential health hazard. The levels of metals within naturally contaminated soils are generally not high enough to cause serious health problems. Living on metal-rich soils does not represent a health risk unless large quantities of soil are digested or metal-rich dust is inhaled. However, small children are particularly exposed to metal-rich dust topsoil in playgrounds and gardens. They are also the most likely ones to eat potentially dangerous metal-rich soil.
Heavy metals are persistent: they do not break down to other chemicals in the environment. Industrially polluted sites usually undergo intensive clean-up and rehabilitation because heavy metals are a health concern once they enter the food chain. Some trace metals are alleged to cause cancer and are also known to cause poisoning.
In contrast naturally contaminated soils have not been subject to risk assessment studies and rehabilitation measures, despite the fact that they frequently possess metal concentrations well above those of such polluted by humans and above environmental quality criteria.
There is a vital need to understand the potential risks and long-term health effects of living on naturally contaminated soils. Future environmental investigations of naturally polluted soils should concentrate on the potential pathways of metals into the food chain and human body. Geologists should be part of such studies as they can provide the essential background information on rock and soil chemistry as well as the chemical forms of heavy metal pollution.
*
选项
答案
C
解析
本题答案的依据是最后一段的第一句,即There is a vital need to understand the potential risks and long-term health effects of living on naturally contaminated soils.
转载请注明原文地址:https://kaotiyun.com/show/d5hd777K
本试题收录于:
职称英语理工类基础题库职称英语分类
0
职称英语理工类基础
职称英语
相关试题推荐
Diet,AlcoholLinkedtoNearlyOneThirdofCancersDietissecondonlytotobaccoasaleading(1)ofcancerand,alongwithalcoh
Primitivehumanslookedlikeanimals.FromLongage,peoplestartedtounderstandtherelationshipbetweensocialbehaviorand
StudiesShowU.S.SpendingDoesn’tGetBestHealthTheUnitedStatesmayspendtwiceasmuchonhealthcareasotherrichc
StudiesShowU.S.SpendingDoesn’tGetBestHealthTheUnitedStatesmayspendtwiceasmuchonhealthcareasotherrichc
DrugAbuse1Theterm"drugabuse"mostoftenreferstotheuseofadrugwithsuchfrequencythatitcausesphysicalormental
SincetheGreatDepression,theUnitedStatesgovernmenthasprotectedfarmersfromdamagingdropsingrainprices.
HousesoftheFutureWhatwillhousesbelikeinthirtyyears’time?Noonereallyknows,butarchitectsaretryingtopredi
SleepLetsBrainFileMemoriesTosleep.Perchancetofile?FindingspublishedonlinethisweekbytheProceedingsoftheNa
Thebestoptionwouldbetocancelthetripaltogether.
Youmustshineyourshoes.
随机试题
销售控制的关键是
A.面罩吸氧B.高压氧舱C.持续低流量吸氧D.间断高流量吸氧E.呼气末正压急性呼吸窘迫综合征治疗应
肾上腺皮质可分泌一组类固醇激素,束状带分泌的激素主要是
糖酵解过程的终产物是
易致休克的胆道疾病是:
手术产新生儿护理措施中错误的是
设计招标的特点主要表现在( )方面。
一、注意事项1.申论考试必须在指定位置用钢笔或圆珠笔作答,并在指定的位置填写(或填涂)自己的姓名及有关信息。2.申论考试与一般的写作考试不同,它是对应考者阅读理解能力、分析能力、提出并解决问题能力和文字表达能力的综合测试。3.请先仔
下列关于春秋决狱的表述中,正确的是()
在窗体上有一个命令按钮Commandl,编写事件代码如下:PrivateSubCommandlClick()DimdlAsDateDimd2AsDatedl=#12/25/2009#d2=
最新回复
(
0
)