. Author manuscript; available in PMC: 2016 Nov 1.

Published in final edited form as: Environ Res. 2015 Sep 25;143(0 0):1–9. doi: 10.1016/j.envres.2015.09.013

Table 2.

Mean and Standard Error (± SE) levels of thyroid stimulating hormone (TSH) and free T4 in maternal serum and perchlorate, nitrate, thiocyanate, and iodide in maternal urine collected during the first half of pregnancy (N= 284).

	% > LOD	Mean ± SE	25^th	50^th	75^th	95^th
Maternal Serum
TSH (mU/L)	100	1.53 ± 0.07	0.80	1.23	1.89	4.13
Free T4 (ng/dL)	100	1.01 ± 0.01	0.95	1.01	1.08	1.20
Maternal Urine (μg/g creatinine)^,^*
		Mean ± SE	25^th	50^th	75^th	95^th
Perchlorate	99.6	3.54 ± 0.2	1.44	2.57	4.41	8.74
Nitrate	100	42149.54 ± 1416.8	27250	33250	50800	88325
Thiocyanate	99.3	1006.46 ± 65.29	372.25	672.00	1290.00	2852.50
Iodide	100	235.39 ± 39.40	89.25	138.50	217.00	520.25

Analytical limit of detection (LOD): Perchlorate = 0.05 ng/ml; Nitrate = 700 ng/ml; Thiocyanate = 20 ng/ml; Iodide = 0.2ng/ml.

^**

Mean ± SE ng/ml creatinine = 110.3 ± 4.9