年职称英语卫生类概括大意练习(16)

XXXX年职称英语卫生类概括大意练习(16)

GeologyandHealth

Theimportanceofparticularmetalsinthehumandiethasbeenrealizedwithi nthepastfewdecades,andtheideathatgeologymightberelatedtohealthhasbeen recognizedforanumberofelementssuchasiodine,zincandselenium.Forexample ,soilswithlowiodinecontentsproducecrops,andanimalsdeficientiniodine.A lackofiodineinthehumandietleadstosomeseriousdiseases.

Theultimatesourceofmetalswithinthehumanbodyisrocks,whichweatherin tosoil,gainingorlosingsomeoftheirchemicalconstituents.Thecropsweeatse lectivelyremovefromthesoiltheelementsthattheyrequireforgrowth.Thewate rwedrinkcontainstraceelementsleachedfromrockandsoil.Thusthegeologyand geochemistryoftheenvironmentshaveeffectsonthechemistryandhealthofplan ts,animalsandpeople.

Sofarthereisnodatatosuggestthatpeoplelivingonmetal-richsoilsexper ienceapotentialhealthhazard.Thelevelsofmetalswithinnaturallycontamina tedsoilsaregenerallynothighenoughtocauseserioushealthproblems.Livingo nmetal-richsoilsdoesnotrepresentahealthriskunlesslargequantitiesofsoi laredigestedormetal-richdustisinhaled.However,smallchildrenareparticu larlyexposedtometal-richtopsoilinplaygroundsandgardens.Theyarealsothe mostlikelyonestoeatpotentiallydangerousmetal-richsoil.

Heavymetalsarepersistent;theydonotbreakdowntootherchemicalsinthee nvironment.Industriallypollutedsitesusuallyundergointensiveclean-upan drehabilitationbecauseheavymetalsareahealthconcernoncetheyenterthefoo dchain.Sometracemetalsareallegedtocausecancerandarealsoknowntocausepo isoning.

Incontrast,naturallycontaminatedsoilshavenotbeensubjecttoriskasse ssmentstudiesandrehabilitationmeasures,despitethefactthattheyfrequent lypossessmetalconcentrationswellabovethoseofsuchpollutedbyhumansandab oveenvironmentalqualitycriteria.

Thereisavitalneedtounderstandthepotentialrisksandlong-termhealthe ffectsoflivingonnaturallycontaminatedsoils.Futureenvironmentalinvesti gationsofnaturallypollutedsoilsshouldconcentrateonthepotentialpathway sofmetalsintothefoodchainandhumanbody.Geologistsshouldbepartofsuchstu

diesastheycanprovidetheessentialbackgroundinformationonrockandsoilche mistryaswellasthechemicalformsofheavymetalpollution.

A.Noevidencetoindicatebadeffectsofnaturallycontaminatedsoil

B.Potentialhazardsofhumancontaminatedsoils

C.Researchonchannelsofheavymetalsgettingintohumanfoodchain

D.Geologyandhealthproblems

E.Rocks-theultimatesourceofsoilpollution

F.Long-termhealtheffectsonchildren

1.Paragraph1

2.Paragraph3

3.Paragraph4

4.Paragraph6

A.industriallypollutedsoils

B.rockandsoilchemistry

C.naturallypollutedsoils

D.thepathwaysofmetalsintothefoodchain

E.theelementofiodine

F.thepersistenceofheavymetals

5.Someseriousd iseasesisconnectedwithdeficiencyof……

6.Itisextremelynecessarytostudythelong-termeffectscausedbylivingo n……

7.Geologistsareindispensableintheresearchprojectongeologyandhealt hduetotheirknowledgeon……

8.Industriallycontaminatedsitesusuallyrequireathoroughclean-updue to……

Key:DABCECBF