05). Low-NBNA scores resulted from low-level prenatal mercury exposure (seafood consumption) should be further validated in the long-term prospective study. Mercury concentration in hair has been found to be an accurate16 and the most frequently useful indicator of individual mercury exposure in children and adults,
and over a million hair samples were examined in a study in the United States.17 And it also has advantages on convenient Akt tumor sample acquisition and storage for monitoring and field studies.18 In this study, the mean total mercury level in maternal hair was 1.20 μg/g, which was higher than those measured in most other Chinese regions, including Beijing (n = 684; mean = 0.14 μg/g), Changchun (n = 920; mean = 0.18 μg/g), Shanghai (n = 938; mean = 1.15 μg/g), and Hangzhou (n = 500; mean = 1.16 μg/g),19 but PFI-2 ic50 was lower than those in the population of Hong Kong (n = 137; mean = 2.2 μg/g and n = 1057; median = 1.7 μg/g).20 Of
the mothers included in our study, 55.02% had higher hair mercury level than the safe hair mercury criterion set by the Environmental Protection Agency (EPA, <1 μg/g).21 For newborns, cord blood analysis is a reliable method for evaluating the level of mercury exposure.22 In the present study, the mean cord blood mercury level was 7.92 μg/L, which is much lower than those found in other fish-eating populations such as Faroe Islands (mean = 22.9 μg/L) and Tokushima (mean = 24.8 μg/L).23 The American National Research Council performed a benchmark dose (BMD) analysis on a number of endpoints in three longitudinal prospective studies in Seychelles Islands, Faroe Islands, and New Zealand. They recommended a BMD lower confidence limit (95% CI of the benchmark dose) of 58 μg/L mercury in cord blood.24 Based on the analysis by the National Research Council, the EPA set a reference dose of 5.8 μg/L (BMD lower confidence limit and/or uncertainty factor = 5.8 μg/L)
for mercury in cord blood.25 In this study, cord blood mercury concentrations were higher than the reference dose in 271 subjects, accounting for 56.34% of the study population. Furthermore, many epidemiological studies have suggested that fetal mercury exposure at doses as low as 5.8 μg/L Methane monooxygenase may have long-term consequences for neurobehavioral development.8 and 26 Maternal blood mercury concentration was also an important biomarker for fetal mercury exposure. The maternal biomarker was initially used to reflect mercury exposure to the mother herself. A strong correlation was found between maternal blood and cord blood mercury levels. However, there was certain variability between the maternal and fetal mercury levels. This study revealed that individual cord and/or maternal blood mercury ratios varied between 0.85 and 22.36 in the 418 mother-neonates pairs and revealed individual differences in mercury concentrations between maternal and fetal circulations during late gestation.