Since pharmaceutical exposures to perchlorate are known to suppress thyroid function in patients with hyperthyroidism, a study of employees at a perchlorate manufacturing plant was conducted to asses whether occupational exposure to perchlorate suppresses thyroid function.
Exposure to perchlorate was assessed by measurement of ambient air concentrations of total and respirable perchlorate particles, and systemic absorption was assessed by measurement of urinary perchlorate excretion.
Airborne exposures ranged from 0.004 to 167 mg total particulate perchlorate per day Urinary perchlorate measurements demonstrated that exposure to the airborne particulate perchlorate resulted in systemic absorption.
Workers were grouped into four exposure categories with mean absorbed perchlorate dosages of 1,4,11 and 34 mg perchlorate per day.
Thyroid function was assessed by measurement of serum thyroid-stimulating hormone, free thyroxine index, thyroxine, triiodothyronine, thyroid hormone binding ratio, thyroid peroxidase antibodies, and by clinical examination.
No differences in thyroid-function parameters were found between the four groups of workers across approximately three orders of magnitude of exposure and of dose.
Thus human thyroid function was not affected by these levels of absorbed perchlorate.
In addition, no clinical evidence of thyroid abnormalities was found in any exposure group. (...)
Mots-clés Pascal : Exposition professionnelle, Médecine travail, Industrie chimique, Perchlorate, Toxicité, Thyroïde pathologie, Teneur air ambiant, Lieu travail, Evaluation, Dose sans effet, Etude cas témoin, Surveillance biologique, Marqueur biologique, Liquide biologique, Urine, Excrétion, Endocrinopathie
Mots-clés Pascal anglais : Occupational exposure, Occupational medicine, Chemical industry, Perchlorates, Toxicity, Thyroid diseases, Ambient air concentration, Work place, Evaluation, No observed effect level, Case control study, Biological monitoring, Biological marker, Biological fluid, Urine, Excretion, Endocrinopathy
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 99-0235458
Code Inist : 002B03L06. Création : 16/11/1999.