Adjusted odds ratios (ORs) with 95% confidence intervals (95% CIs) for primary hyperparathyroidism (defined as parathyroid hormone >70 pg/mL and corrected calcium ≥9.5 mg/dL) and secondary hyperparathyroidism (defined as parathyroid hormone >70 pg/mL and corrected calcium <9.5 mg/dL) by creatinine-corrected urinary concentrations of perchlorate, nitrate, and thiocyanate among the United States adults, NHANES 2005–2006. This evidence concerns the gene PTH and secondary hyperparathyroidism.