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

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 (ß = -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.

Associations between prenatal metal exposure and growth rate in children: Based on Hangzhou Birth Cohort Study.

BACKGROUND: It has been reported that prenatal metal exposure is associated with child anthropometry. However, studies focusing on the growth rate of anthropometry among children have not been conducted. This study aimed to examine associations between the exposure of multiple metals during pregnancy and the growth rate of anthropometry among offspring. METHODS: 743 mother-child pairs from the Hangzhou Birth Cohort Study (HBCS) were included. Levels of eleven metals in mother's blood during pregnancy were measured. Offspring had a mean of 5.7 measurements on anthropometric indicators including weight, length/height, head circumference, and body mass index (BMI) within 1.5 years of birth. Generalized estimating equation (GEE) model was used to investigate the associations between maternal metal exposure and growth rate of anthropometric indicators in children. Stratification analysis by sex was also examined. RESULTS: Levels of selenium (Se, ß = 0.213, 95 % CI = 0.017 to 0.409, P = 0.033) were positively associated with length/height gain per month in children. Levels of chromium (Cr, ß = 0.025, 95 % CI = 0.018 to 0.033, P < 0.001) were positively associated with the rate of weight gain. Levels of manganese (Mn, ß = -0.030, 95 % CI = -0.052 to -0.008, P = 0.009) and cobalt (Co, ß = -0.012, 95 % CI = -0.024 to -0.000, P = 0.044) were inversely associated with growth rate of head circumference. Children with higher maternal Mn levels had a lower BMI change rate. Associations between metals and growth rate were stronger in girls than in boys. Besides, significant associations between metal mixtures and growth rate were found. CONCLUSION: Prenatal exposure to Se, Cr, Mn, and Co was associated with growth rate in children, with sex-specific disparities. Our results suggested important effects of maternal exposure to multiple metals on development in offspring.

Total arsenic, dimethylarsinic acid, lead, cadmium, total mercury, methylmercury and hypertension among Asian populations in the United States: NHANES 2011-2018.

BACKGROUND: Non-Hispanic Asians (NHA) in USA have been reported with higher arsenic (As), lead (Pb), cadmium (Cd), mercury (Hg) and their specific species levels, comparing with non-NHA. This study aimed to investigate the associations of these metal/metalloid levels with blood pressure levels and prevalence of hypertension among general NHA using the 2011-2018 National Health and Nutrition and Examination Survey (NHANES) data. METHODS: The study included participants aged 20 years and older with determinations of As, Dimethylarsinic acid (DMA), Pb, Cd, Hg and methyl-Hg (MeHg) in blood (n = 10, 177) and urine (n = 5, 175). These metals/metalloid levels were measured by inductively coupled plasma mass spectrometry. Systolic (SBP) and diastolic blood pressure (DBP) levels were examined through a standardized protocol. Censored normal regression model and logistic regression model were employed to explore the associations of As, DMA, Pb, Cd, Hg and MeHg levels with blood pressure levels and prevalence of hypertension respectively, and potential confounders were adjusted in these regression models. Quantile-based g-computation approach was used to analysis joint effect of metals mixture on blood pressure level and hypertension. RESULTS: For NHA, urinary As and Hg levels were associated with increased DBP level; Higher blood Hg and MeHg levels were related to increased blood pressure levels and hypertension; However, negative association was observed between urinary Cd and SBP level; Blood metals mixture (including blood Pb, Cd and Hg) was associated with increased DBP level, but not for hypertension. For non-NHA, urinary As and DMA levels were associated with increased SBP level, but not DBP level and prevalence of hypertension; Urinary Pb level was associated with decreased DBP level; Nevertheless, positive associations were observed between blood Pb levels and SBP and prevalence of hypertension; Blood Hg level was associated with decreased DBP level and prevalence of hypertension; Furthermore, blood MeHg level was associated with decreased DBP level; Positive association was observed between blood metals mixture and increased SBP level among non-NHA. CONCLUSIONS: Highly exposed to Hg level among NHA was associated with increased blood pressure levels and prevalence of hypertension. Urinary As level was associated with increased DBP level among NHA. Furthermore, blood metals mixture was related to increased DBP level among NHA. Further prospective studies with larger sample size should be performed to warrant the results.

Association between vitamin D/calcium intake and 25-hydroxyvitamin D and risk of ovarian cancer: a dose-response relationship meta-analysis.

BACKGROUND: The association between vitamin D/calcium and risk of ovarian cancer is still a debatable point. The aim of our study was to systematically investigate the association between vitamin D/calcium, and the risk of ovarian cancer and estimate their dose-response association quantitatively. METHODS: PubMed, EMBASE, and Web of Science databases were searched to identify relevant observational studies. Two investigators screened citations and extracted data independently. Data were extracted and the association between vitamin D/calcium and ovarian cancer risk was estimated by calculating pooled relative risks (RRs). Subgroup analyses, publication bias estimation, and dose-response analyses were carried out as well. RESULTS: In total, 21 articles involving 980,008 participants were included in our present study. No significant association was observed between total vitamin D intake and ovarian cancer risk (RR: 1.02; 95% CI, 0.89-1.16, p = 0.81). Further subgroup analysis suggested that neither dietary vitamin D intake (RR: 0.80; 95% CI, 0.62-1.03, p = 0.09) nor supplementary vitamin D intake (RR: 0.98; 95% CI, 0.85-1.13, p = 0.80) was associated with the risk of ovarian cancer. As for calcium, total calcium intake was found to be statistically inversely associated with ovarian cancer risk in case-control studies (RR: 0.73; 95% CI, 0.63-0.86, p < 0.001) but not in cohort studies (RR: 1.05; 95% CI, 0.90-1.24, p = 0.52). Besides, supplementation with calcium plus vitamin D was not effective for the prevention of ovarian cancer (p = 0.98). Of note, dose-response analysis based on cohort studies suggested a potential inverse U-shape relationship between calcium intake (including total calcium and dietary calcium) and ovarian cancer risk, which indicated that low dose of calcium intake might reduce ovarian cancer risk while high dose of calcium intake might not. CONCLUSIONS: Taken together, vitamin D could not decrease the risk of ovarian cancer. The role of calcium intake was not proven for reducing ovarian cancer risk. Besides, no evidence showed combinative use of calcium and vitamin D have additional benefits for ovarian cancer prevention.