Associations among neighborhood walkability, metal exposure, and sex steroid hormone levels: Results from Hangzhou Birth Cohort Study Ⅱ

Jiawei Fang; Yexinyi Zhou; Yinyin He; Jiena Zhou; Jun Tang; Qiong Luo; Jing Guo; Guangdi Chen

doi:10.1016/j.ecoenv.2024.116427

Associations among neighborhood walkability, metal exposure, and sex steroid hormone levels: Results from Hangzhou Birth Cohort Study Ⅱ

Ecotoxicol Environ Saf. 2024 May 9:278:116427. doi: 10.1016/j.ecoenv.2024.116427. Online ahead of print.

Authors

Jiawei Fang¹, Yexinyi Zhou¹, Yinyin He¹, Jiena Zhou¹, Jun Tang², Qiong Luo³, Jing Guo⁴, Guangdi Chen⁵

Affiliations

¹ Department of Public Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China; Key Laboratory of Reproductive Genetics (Zhejiang University), Ministry of Education, Hangzhou, Zhejiang 310006, China.
² Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310052, China.
³ Department of Obstetrics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310006, China.
⁴ Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310006, China.
⁵ Department of Public Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China; Key Laboratory of Reproductive Genetics (Zhejiang University), Ministry of Education, Hangzhou, Zhejiang 310006, China. Electronic address: chenguangdi@zju.edu.cn.

PMID: 38733803
DOI: 10.1016/j.ecoenv.2024.116427

Abstract

Background: Neighborhood walkability may influence maternal-fetal exposure to environmental hazards and maternal-fetal health (e.g., fetal growth restriction, reproductive toxicity). However, few studies have explored the association between neighborhood walkability and hormones in pregnant women.

Methods: We included 533 pregnant women from the Hangzhou Birth Cohort Study II (HBCS-II) with testosterone (TTE) and estradiol (E2) measured for analysis. Neighborhood walkability was evaluated by calculating a walkability index based on geo-coded addresses. Placental metals were measured using inductively coupled plasma mass spectrometry (ICP-MS). TTE and E2 levels in umbilical cord blood were measured using chemiluminescence microparticle immunoassay (CMIA). Linear regression model was used to estimate the relationship between the walkability index, placental metals, and sex steroid hormones. Effect modification was also assessed to estimate the effect of placental metals on the associations of neighborhood walkability with TTE and E2.

Results: Neighborhood walkability was significantly linked to increased E2 levels (P trend=0.023). Compared with participants at the first quintile (Q1) of walkability index, those at the third quintiles (Q3) had lower chromium (Cr) levels (β = -0.212, 95% CI = -0.421 to -0.003). Arsenic (As), cobalt (Co), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), antimony (Sb), selenium (Se), tin (Sn), and vanadium (V) were linked to decreased TTE levels, and cadmium (Cd) was linked to increased TTE levels. No metal was significantly associated with E2 levels in trend analysis. In the analysis of effect modification, the associations of neighborhood walkability with TTE and E2 were significantly modified by Mn (P = 0.005) and Cu (P = 0.049) respectively.

Conclusion: Neighborhood walkability could be a favorable factor for E2 production during pregnancy, which may be inhibited by maternal exposure to heavy metals.

Keywords: Estradiol; Metals; Neighborhood walkability; Pregnant women; Testosterone.