天然钍对作业工人健康影响的研究

Studyoftheeffectofnaturalthoriumontheworker'shealth

为研究包钢的原料中所含天然钍对作业工人健康的影响，对５９８５人的暴露队列进行了１７年的流行病学调查。结果发现，作业工人外周血淋巴细胞染色体畸变率随年附加有效剂量的增加而升高（与对照组比较Ｐ＜０．０１）。工龄为５～１４年者增加较快，１５年后增加缓慢，趋于平衡。尘肺分析结果提示，天然钍可能增强ＳｉＯ２的致肺纤维化作用。肿瘤死亡率除胃癌外，其余ＲＲ均大于１，但无统计学意义。相距一年的两次植物血球凝集素（ＰＨＡ）皮试反应均有增强，但外周血淋巴细胞离体照射后，染色体畸变未见适应性。女工妊娠期从事钍作业，其所生子女的智力发育无明显异常。

ForstudyingtheefectsofnaturalthoriumcontainedintherawmaterialofIronoreofBaotoulronandSteelCompanyonworker'shealth,anepidemiologicalinvestigationhasbeencarriedoutfor17yearsamongacohortof5985workersexposedtothori-um.Theresultsshowedthattherateofchromosomeaberrationsoftheperipherallymphocytesrisewiththeincreaseintheaddedeffectivedoses.Therewasasignificantdifferencebetweentheexposedgroupandthecontrol(P<0.01).Intheworkersof5～14years'standing,theriseintheaberrationratewasrelativelyrapid,butitwasslowerandtendedtobalanceinthoseofmorethan15years'standing.Theanalysisofpneumoconiosissuggeststhatthenaturalthoriummayenhancethefibrogenicactionofsilicaonthelungtissues.Exclusiveofstomachcancer,theRRofothercarcinomasweremorethan1,butwerewithoutstatisticalsignificance.ThePHAskintestsperformedtwiceatoneyearintervalshowedthatthereactiontothetestisintensified.Adaptationofchromosomeaberrationwasnotseenafterirradia-tionofthelymphocytesfromtheperipheralcirculationinvitro.Nonoticeableimpairmenthasbeenfoundtotheinteligenceofthechildrenwhosemotherswereexposedtothoriumduringtheirpregnan-cy.