Table 1.

Concentrations (μg/L) of metals in urine specimens from pregnant black women attending a Medicaid-serving prenatal clinic, Houston, TX, 2017Element

	Recovery rate (%)	Precision (%)	LOD (μg/L)	N of ND (%)	GM	Mean	SD	Min	25th percentile	50th percentile	75th percentile	Max
Ag	113	8.4	0.142	33 (26.2)	0.25	0.32	0.23	< 0.10	0.10	0.24	0.64	0.91
Al	161	10.7	0.660	0 (0.0)	23.33	45.07	120.70	2.12	8.89	33.39	48.98	1346.64
As	116	4.9	0.282	0 (0.0)	9.52	24.50	40.10	0.21	3.37	5.89	26.10	275.13
Ba	124	3.8	0.170	0 (0.0)	2.77	3.95	3.54	0.27	1.50	3.01	5.26	22.36
Cd	112	10.8	0.176	12 (9.5)	0.37	0.58	0.52	< 0.12	0.14	0.32	1.14	1.86
Co	108	5.8	0.286	36 (28.6)	0.28	0.43	0.50	< 0.20	0.20	0.20	0.44	3.62
Cr	106	5.1	0.303	0 (0.0)	1.50	5.01	5.16	0.21	0.21	5.74	8.62	26.07
Cu	126	13.2	0.316	3 (2.4)	8.00	13.38	14.63	< 0.22	4.52	8.00	17.66	88.80
Ni	107	6.4	0.279	33 (26.2)	0.45	0.81	0.93	< 0.20	0.20	0.26	1.25	4.74
Pb	125	6.1	0.167	33 (26.2)	0.24	0.36	0.47	< 0.12	0.12	0.22	0.45	4.29
Sb	116	6.8	0.154	33 (26.2)	0.29	0.39	0.30	< 0.11	0.11	0.26	0.76	1.27
Se	115	5.5	0.124	0 (0.0)	75.69	101.75	76.87	6.41	50.28	84.31	131.52	498.75
Tl	117	5.0	0.160	33 (26.2)	0.12	0.15	0.10	< 0.11	0.11	0.11	0.19	0.63
V	111	4.9	0.284	35 (27.8)	0.24	0.29	0.24	< 0.20	0.20	0.20	0.26	2.40
Zn	118	6.5	0.361	0 (0.0)	402.53	559.78	504.80	45.28	231.35	368.10	741.63	2874.52

Total number of samples is 126 for all metals except As (n = 131). Precision shown as relative standard deviation (%) among 10 replicate samples

LOD limit of detection, Max maximum, Min minimum, ND non-detect, GM geometric mean, SD standard deviation