Dietary Patterns Are Not Consistently Associated with Variability in Blood Lead Concentrations in Pregnant British Women

Maternal diet quality during pregnancy and biomarkers of potentially toxic trace element exposure: Data from the ELFE cohort

The contribution of the diet to potentially toxic trace element exposure in pregnancy has been rarely addressed. The objective of the present study was to determine the association between the maternal diet during pregnancy and biomarkers of exposure for arsenic (As), mercury (Hg) and lead (Pb) at delivery. As was assessed in maternal urine, Hg in maternal hair, and Pb in cord blood, as a proxy for in utero exposure. Based on 2995 women from the ELFE nationwide birth cohort, higher scores for dietary patterns considered healthy were associated with higher concentrations of As and Hg in maternal matrices. Levels of cord blood Pb were inconsistently associated with dietary patterns considered healthy, and lower with a dietary pattern driven by milk and breakfast cereals. Lower levels of Hg were associated with higher Western dietary pattern scores. In conclusion, higher levels of maternal urinary As and hair Hg are associated with diets considered as "Healthy", while cord blood Pb was not strongly correlated with dietary exposure.

Pro-vegetarian dietary patterns and essential and heavy metal exposure in children of 4-5-years from the INfancia y medio Ambiente cohort (INMA)

Dietary patterns provide a comprehensive assessment of food consumption, including essential nutrients and potential exposure to environmental contaminants. While pro-vegetarian (PVG) dietary patterns have shown health benefits in adults, their effects on children are less well studied. This study aims to explore the association between children's adherence to the most common PVG dietary patterns and their exposure to metals, assessed through urine concentration. In our study, we included a population of 723 children aged 4-5-years from the INfancia y Medio Ambiente (INMA) cohort in Spain. We calculated three predefined PVG dietary patterns, namely general (gPVG), healthful (hPVG), and unhealthful (uPVG), using dietary information collected through a validated Food Frequency Questionnaire. Urinary concentrations of various essential and heavy metals (Co, Cu, Zn, Se, Mo, Pb, and Cd) were measured using mass spectrometry. Additionally, urinary arsenic speciation, including arsenobetaine (AsB), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA), and inorganic arsenic (iAs), was measured. The sum of urinary MMA and iAs was used to assess iAs exposure. We estimated primary (PMI) and secondary iAs methylation (SMI) indices. To explore the association between PVG dietary patterns in quintiles and metal exposure, we utilized multiple-adjusted linear regression models and the quantile g-computation approach. Compared with the lowest quintile, participants in the highest quintile of gPVG showed a 22.7% lower urinary Co (95% confidence interval (CI): -38.7; -1.98) and a 12.6% lower Se (95%CI: -22.9; -1.00) concentrations. Second quintile of adherence to hPVG was associated with a 51.7% lower urinary iAs + MMA concentrations (95%CI: -74.3; -8.61). Second quintile of adherence to an uPVG was associated with a 13.6% lower Se levels (95%CI: -22.9; -2.95) while the third quintile to this pattern was associated with 17.5% lower Mo concentrations (95%CI: -29.5; -2.95). The fourth quintile of adherence to gPVG was associated with a 68.5% higher PMI and a 53.7% lower SMI. Our study showed that adherence to a gPVG dietary pattern in childhood may modestly reduce the intakes of some essential metals such as Co and Se. Further investigations are warranted to explore any potential health implications.

Automated lead toxicity prediction using computational modelling framework

Background

Lead, an environmental toxicant, accounts for 0.6% of the global burden of disease, with the highest burden in developing countries. Lead poisoning is very much preventable with adequate and timely action. Therefore, it is important to identify factors that contribute to maternal BLL and minimise them to reduce the transfer to the foetus. Literacy and awareness related to its impact are low and the clinical establishment for biological monitoring of blood lead level (BLL) is low, costly, and time-consuming. A significant contribution to an infant's BLL load is caused by maternal lead transfer during pregnancy. This acts as the first pathway to the infant's lead exposure. The social and demographic information that includes lifestyle and environmental factors are key to maternal lead exposure.

Results

We propose a novel approach to build a computational model framework that can predict lead toxicity levels in maternal blood using a set of sociodemographic features. To illustrate our proposed approach, maternal data comprising socio-demographic features and blood samples from the pregnant woman is collected, analysed, and modelled. The computational model is built that learns from the maternal data and then predicts lead level in a pregnant woman using a set of questionnaires that relate to the maternal's social and demographic information as the first point of testing. The range of features identified in the built models can estimate the underlying function and provide an understanding of the toxicity level. Following feature selection methods, the 12-feature set obtained from the Boruta algorithm gave better prediction results (kNN = 76.84%, DT = 74.70%, and NN = 73.99%).

Conclusion

The built prediction model can be beneficial in improving the point of care and hence reducing the cost and the risk involved. It is envisaged that in future, the proposed methodology will become a part of a screening process to assist healthcare experts at the point of evaluating the lead toxicity level in pregnant women. Women screened positive could be given a range of facilities including preliminary counselling to being referred to the health centre for further diagnosis. Steps could be taken to reduce maternal lead exposure; hence, it could also be possible to mitigate the infant's lead exposure by reducing transfer from the pregnant woman.

Periconceptional maternal diet quality influences blood heavy metal concentrations and their effect on low birth weight: the Japan Environment and Children's Study

BACKGROUND

Both poor maternal nutrition and toxic heavy metal exposure influence foetal growth and development. However, whether consumption of a variety of healthy foods modifies the association between prenatal heavy metal exposure and foetal growth is unknown.

OBJECTIVE

We examined whether long-term maternal diet quality in periconception modifies the associations between maternal circulating concentrations of heavy metals and foetal growth.

DESIGN

Data of 72,317 Japanese women who delivered singleton infants was extracted from the Japan Environment and Children's Study. Maternal diet over a 1-year before the first trimester of pregnancy was assessed using a validated food frequency questionnaire, and overall diet quality was determined using the balanced diet score based on the Japanese Food Guide Spinning Top. Maternal whole-blood concentrations of mercury (Hg), lead (Pb) and cadmium (Cd) were measured during the second/third trimester of pregnancy. Bayesian inference of multiple linear regression analysis was performed to evaluate the relationships between maternal diet quality and the blood concentrations of heavy metals; Bayesian logistic regression was used to analyse the risk of low birth weight (LBW; <2,500 g).

RESULTS

After controlling for confounders, a high maternal balanced diet score was associated with low concentrations of blood Pb and Cd and high Hg. While all heavy metals assessed were positively associated with LBW risk, a higher maternal balanced diet score was negatively associated with LBW risk. A high-quality maternal diet attenuated the effect of Pb on LBW, an effect that was more marked at high blood Pb concentrations.

CONCLUSION

A high-quality, 'well-balanced' diet prior to conception may reduce exposure to some heavy metals and mitigate the elevated risk of LBW associated with prenatal Pb exposure in Japanese mother-child pairs.

Prenatal Monitoring of Perinatal Pregnant Women and Fetus Based on a Smart Electronic Fetal Monitoring System

The aim of the study is to study the prenatal monitoring of perinatal pregnant women based on a smart electronic fetal monitoring system. Through the comparative analysis of 230 pregnant women in maternal and child health care hospital who received fetal heart monitoring during the perinatal period and those who did not receive fetal heart monitoring during the perinatal period, cases of fetal distress, neonatal asphyxia, and cesarean section were observed in both groups. Results show that the incidences of fetal complications and cesarean sections in the experimental group were 16.36% and 36.82%, which was significantly higher than 4.50% and 17.50% in the control group(p < 0.05); the neonatal mild and severe asphyxia rates in the experimental group were 3.18% and 1.36%, which were significantly lower than 9.50% and 6.50% in the control group (p < 0.05). The experimental results show that the correct application of fetal heart rate monitoring in the perinatal period can aid in early detection and dealing with fetal distress and reduce the occurrence of various complications such as neonatal asphyxia. It is worthy to be popularized and applied in clinics.

Determinants of blood and saliva lead concentrations in adult gardeners on urban agricultural sites

Soil Pb concentrations at urban agriculture sites (UAS) commonly exceed recommended safe levels. There is a lack of evidence regarding uptake of Pb by gardeners using such sites for food crops. Our study aimed to elucidate whether gardening in soil with raised Pb levels results in Pb body burdens of concern to health, and to assess confounding factors influencing Pb body burden. Our cross-sectional case study measured Pb in saliva and blood of UAS gardeners (n = 43), soil and produce samples from their UAS, and home tap water. Blood and saliva Pb concentrations were compared with those from non-UAS gardener controls (n = 29). A health risk threshold of 5 µg dL^-1 blood Pb level (BLL) was selected in keeping with international guidance. Detailed surveys investigated individuals' anthropometrics and potential Pb exposures from diet, and historic and everyday activities. Saliva was not found to be a suitable biomarker of adult Pb exposure in this context. Predictors of higher BLLs were being older, being male and eating more root vegetables and shrub fruit. Eating more green vegetables predicted a lower BLL, suggesting a protective effect against Pb uptake. UAS gardeners' BLLs (geometric mean 1.53; range 0.6-4.1 µg dL^-1) were not significantly higher (p = 0.39) than the control group (geometric mean 1.43; range 0.7-2.9 µg dL^-1). All BLLs were below 5 µg dL^-1 except one resulting from occupational exposure. Having paired the UAS gardeners with closely matched controls, we found Pb in UAS soils (with range 62-1300 mg kg^-1from common urban sources) unlikely to pose an additional risk to adult health compared to their neighbours who did not access UAS. As such, other Pb sources may be the dominant factor controlling BLL.

Trends of Blood Lead Levels in US Pregnant Women: The National Health and Nutrition Examination Survey (2001–2018)

Objectives

This study investigates the trends of blood lead levels in US pregnant women based on the National Health and Nutrition Examination Survey from 2001 to 2018.

Methods

A total of 1,230 pregnant women were included in this study. The weighted logistic regression was applied to analyze the association between sociodemographic characteristics with high blood levels. We computed the blood lead levels for each survey period from 2001–2002 to 2017–2018. Moreover, we used the adjusted linear regression model to investigate the time-related change in blood lead level. The odds ratio (OR) with a 95% confidence interval (CI) was calculated accordingly.

Results

The mean blood lead was 0.73 ± 0.03 ug/dL, and high blood lead was observed in 2.53% of individuals. The Mexican Americans were more associated with high blood lead than the non-Hispanic white (OR, 1.072; 95% CI, 1.032-1.112). The mean blood lead level has decreased from 0.97 ug/dL in 2001–2002 to 0.46 ug/dL in 2013–2014. Afterward, a slight increase was observed with the mean blood lead of 0.55 ug/dL in 2015–2016 and 0.53 ug/dL in 2017-2018. In the adjusted linear regression model, each year's increase would lead to a 0.029 ug/dL decrease in blood lead (P < 0.001). However, no significant change was observed in the 2017–2018 cycle compared with 2009–2010 (P = 0.218).

Conclusion

This study summarized the trend of blood lead levels in US pregnant women over 2001–2018. Continued effort is still required to control lead sources better and protect this population from lead exposure.