Effects of occupational lead exposure on lumbar vertebral fracture in male workers.

Abstract

To investigate the effects of occupational lead exposure on lumbar vertebral fracture in exposed male workers. One hundred and fifty-two lead-exposed male workers in a storage battery plant in Shanghai were selected as the study population. The blood lead (BPb) and the urinary lead (UPb) were measured by graphite-furnace atomic absorption spectrometry (GF-AAS). Bone mineral density (BMD) was measured by the monophoton absorptiometry(SPA-4) and Z score was determined. Anteroposterior and lateral lumbar spinal X-ray films were taken to determine lumbar vertebral fracture. For the occupationally lead-exposed workers, geometric mean of BPb was 0.85 (0.33 approximately 1.90) micromol/L, geometric mean of UPb was 4.84 (0.46 approximately 21.31) microg/g Cr, and the prevalence of lumbar vertebral fracture was 19.7%. The prevalence of lumbar vertebral fracture would increase with the increase of age and work year, but with no significantly statistical difference (P > 0.05). The bone mineral density (BMD) would decrease with the increase of BPb and UPb (P < 0.05). The prevalence of lumbar vertebral fracture would increase significantly with the increase of the lead exposure (P < 0.05) with the linear correlation (P < 0.05). The prevalence of lumbar vertebral fracture would increase significantly with the decrease of the bone mass (P < 0.01) with the linear correlation (P < 0.01). The occupational exposure to lead could cause the decrease of the bone mineral density and the increase of the prevalence of lumbar vertebral fracture. The development of lumbar vertebral fracture is associated with the decrease of bone mass.