铅对作业工人甲状腺功能的影响

目的　了解铅对作业工人甲状腺功能的影响。方法　选择暴露于铅作业环境下的人群 ,了解工人作业工龄 ,采用火焰原子吸收光谱法测定其作业环境中铅浓度 ,用原子吸收光谱法测定作业工人血铅 (PbB)浓度 ,用血液锌原卟啉测定仪测定血锌原卟啉 (ZPP)浓度 ,用放射免疫分析法检测血清中促甲状腺素 (TSH)、三碘甲状腺原氨酸 (T3)、甲状腺素 (T4 )、游离T3(FT3)、游离T4 (FT4 ) 5项甲状腺功能指标。结果　血铅 >2 .88μmol/L时 ,T3(1 .54± 0 .39)nmol/L]、FT3(5 .50± 1 .2 6)pmol/L]含量明显低于血铅 (1 .92～ 2 .88) μmol/L组 T3(1 .71± 0 .45)nmol/L、FT3(6 .1 2± 1 .64)pmol/L] ,差异有显著性(P <0 .0 5)。铅作业工龄长短对甲状腺激素 (TH)含量未见明显影响。结论　高浓度血铅可能抑制了T4 的脱碘 ;铅作业工龄对甲状腺功能未见明显影响

Effects of lead on thyroid function of occupationally exposed workers

OBJECTIVE: To explore the effects of lead on the thyroid function of occupationally exposed workers. METHOD: 157 workers occupationally exposed to lead in a smelting factory were investigated. The concentration of lead in air at workshop was measured by flame atomic absorption spectrophotometry (FAAS) and the levels of blood lead (PbB) by atomic absorption spectrophotometry (AAS), zinc protoporphyrin (ZPP) by ZnPP meter, as well as the indexes of thyroid function, thyroid-stimulating hormone (TSH), triiodothyronine (T(3)), thyroxin (T(4)), free T(3) (FT(3)), and free T(4) (FT(4)) in serum by radioimmunoassay. RESULTS: The workers with higher level of blood lead (> 2.88 micro mol/L) showed lower levels of T(3) (1.54 +/- 0.39) nmol/L] and FT(3) (5.50 +/- 1.26) pmol/L] than those with lower blood lead level PbB: (1.92 approximately 2.88) micro mol/L group, T(3): (1.71 +/- 0.45) nmol/L, FT(3): (6.12 +/- 1.64) pmol/L, P < 0.05]. There was no obvious effect of length of service on thyroid hormone of exposed workers. CONCLUSION: Higher level of blood lead may cause certain damage to thyroid function by inhibiting deiodination of T(4). No obvious relation between length of service and thyroid function was found.