Table 1.

Studies reporting percent methylmercury (of total mercury) in maternal blood or cord blood.

Reference	Location	N	Matrix	THg (μg/L) Mean ± 1 SD (range)	MeHg (μg/L) Mean ± 1 SD (range)	IHg Mean ± 1 SD (range)	%MeHg (of THg) Mean ± 1 SD (range)
This study	Charleston, South Carolina, USA	83	Early gestation, Maternal blood	0.87 ± 0.79 (0.02–3.9)	0.58 ± 0.61 (0.01–2.7)	0.30 ± 0.331 (0–2.0)	63 ± 24 (10–114)
This study	Charleston, South Carolina, USA	83	Late gestation, Maternal blood	0.79 ± 0.75 (0.06–4.0)	0.46 ± 0.41 (0.01–2.1)	0.33 ± 0.411 (0–2.1)	61 ± 22 (12–117)
5-6	Lisbon, Portugal	150	Maternal blood	4.82 ± 2.31 (1.03–12.0)	2.73 ± 1.52 (0.47–9.12)	4.82 ± 2.311 (1.03–12.0)	56.62
7	Greenville, South Carolina, USA	7	Cord blood	0.34 (BDL-0.67)	0.23 (0.061–0.73)		69 (25–124)
8	Sweden	148	Early gestation, Maternal blood		0.943 (<BDL-6.8)	0.373 (<BDL-4.2)	72 (22–95)4
8	Sweden	112	Late gestation, Maternal blood		0.733 (<BDL-2.8)	0.323 (<BDL–1.9)	Not given
9	Korea	400	Maternal blood	5.275 (5.00–5.57)	4.055 (3.81–4.32)		78.535 (77.09–79.97)
10	Baltimore, Maryland, USA	263	Cord blood	1.77 (1.58–1.97)6	1.45 (1.26–1.65)6	0.43 (0.38–0.48)6	74.6 (71.2–78.1)6

IHg (inorganic mercury), MeHg (methylmercury), SD (standard deviation), THg (total mercury)

¹IHg (estimated) = THg-MeHg

²Range not given

³Median

⁴Range for 90% of the samples

⁵Geometric mean

⁶95% confidence interval