Association Between The Prenatal Pahs Exposure And The DNA Telomere Length In Umbilical Cord Blood Lymphocytes

Objectives:1. Being considered as biomarkers, monohydroxy polycyclic aromatic Hydrocarbons(OH-PAHs), such as 2-hydroxynathalene(2-NAP), 2-hydroxyfluorene(2-FLU), 9-hydroxyphenanthrene(9-PHE), 1-hydroxypyrene(1-PYR) are used to evaluate the exposure level of prenatal PAHs in the City by cross-sectional study. 2. To assess the relationship between the OH-PAHs exposure level in urine and the telomere length in umbilical cord blood lymphocytes.Methods:Signing the informed consent form, 352 pregnant women were recruited and inquired about demographic and obstetric information during the period of April 2009 to April 2010. OH-PAHs in urine has been measured by HPLC-FLD, as well as the telomere length in umbilical cord blood lymphocytes been tested by RT-PCR.Results:1. The prenatal urinary mean concentrations of 2-NAP, 2-FLU, 9-PHE,1-PYR and ∑OH-PAHs are 0.77, 0.28, 0.27, 0.12, 1.42μg/mmol Cr respectively. 2. The result of Spearman rank correlation shows that there are significant statistical correlations among the 2-NAP, 2-FLU, 9-PHE, 1-PYR and ∑OH-PAHs(P<0.05). The correlation coefficient between 2-NAP and ∑OH-PAHs is 0.849, which is highest among the comparison of the ∑OH-PAHs and the four metabolites of PAH.3. Through the Spearman rank correlation analyzing, the result shows there are negative correlation between 9-PHE, 1-PYR, ∑OH-PAHs and TL. The correlation coefficients are-0.11,-0.13,-0.07 respectively. 4. The results of stratified analysis indicate that Leukocyte telomere length(LTL) shortens with the increase of OH-PAHs.Conclusions:1. 2-NAP is a better sign for ∑OH-PAHs, which can reflect the internal exposure level of PAHs if integrating with other metabolites of PAHs accurately. 2. Telomere length will shorten with the increasing of PAHs exposure.