Determination of Thresholds of Radioactive Iodine Uptake Response With Clinical Exposure to Perchlorate: A Pooled Analysis. Issue 4 (April 2018)

• Record Type: Journal Article
• Authors: Bruce, Gretchen M.; Corey, Lisa M.; Pearce, Elizabeth N.; Braverman, Lewis E.; Pleus, Richard C.
• Is Part Of: Journal of occupational and environmental medicine. Volume 60:Issue 4(2018)
• Publication Date: 2018-04
• Subjects: perchlorate -- pooled clinical studies -- RAIU -- thyroid; Medicine, Industrial -- Periodicals; Environmental health -- Periodicals; Occupational Medicine -- Periodicals; Environmental Medicine -- Periodicals; Environmental health; Medicine, Industrial; Periodicals; Electronic journals; 616.9803
• DOI: 10.1097/JOM.0000000000001239
• Languages: English
• ISSNs: 1076-2752

Abstract

Abstract : Objective: To conduct a more robust examination of perchlorate exposure on iodide uptake inhibition (IUI) using pooled data from four clinical studies of perchlorate exposure. Methods: To establish a response threshold for IUI, data were analyzed using segmented linear regression and benchmark dose (BMD) analysis. Results: Segmented linear regression applied to data for 69 subjects representing nine doses identified a breakpoint corresponding to a change in the slope of the dose–response relationship of 3.0 mg/d perchlorate. The estimated BMD for a 20% decrease in iodine uptake was 2.3 mg/d, with a lower 95% confidence interval limit of 1.6 mg/d. Conclusions: A threshold dose for IUI from perchlorate exposure of 1.6 to 3.0 mg/d (0.021 to 0.038 mg/kg d) was estimated using two modeling approaches. These estimates are slightly higher than the lowest observed effect level of 0.02 mg/kg d from the Greer Study. Abstract : Supplemental Digital Content is available in the text