Maternal blood cadmium, lead and arsenic levels, nutrient combinations, and offspring birthweight

Abstract

BackgroundCadmium (Cd), lead (Pb) and arsenic (As) are common environmental contaminants that have been associated with lower birthweight. Although some essential metals may mitigate exposure, data are inconsistent. This study sought to evaluate the relationship between toxic metals, nutrient combinations and birthweight among 275 mother-child pairs.MethodsNon-essential metals, Cd, Pb, As, and essential metals, iron (Fe), zinc (Zn), selenium (Se), copper (Cu), calcium (Ca), magnesium (Mg), and manganese (Mn) were measured in maternal whole blood obtained during the first trimester using inductively coupled plasma mass spectrometry. Folate concentrations were measured by microbial assay. Birthweight was obtained from medical records. We used quantile regression to evaluate the association between toxic metals and nutrients due to their underlying wedge-shaped relationship. Ordinary linear regression was used to evaluate associations between birth weight and toxic metals.ResultsAfter multivariate adjustment, the negative association between Pb or Cd and a combination of Fe, Se, Ca and folate was robust, persistent and dose-dependent (p < 0.05). However, a combination of Zn, Cu, Mn and Mg was positively associated with Pb and Cd levels. While prenatal blood Cd and Pb were also associated with lower birthweight. Fe, Se, Ca and folate did not modify these associations.ConclusionSmall sample size and cross-sectional design notwithstanding, the robust and persistent negative associations between some, but not all, nutrient combinations with these ubiquitous environmental contaminants suggest that only some recommended nutrient combinations may mitigate toxic metal exposure in chronically exposed populations. Larger longitudinal studies are required to confirm these findings.Electronic supplementary materialThe online version of this article (doi:10.1186/s12889-017-4225-8) contains supplementary material, which is available to authorized users.

RW‐2018—Research Workshop: The Effect of Nutrition on Epigenetic Status, Growth, and Health

“…As an example, the average newborn has between 50 and 200 xenobiotics in their cord blood at birth. From these new technologies, we have discovered that 2 of these xenobiotics, lead and cadmium, are found together in humans about 50% of the time . Neither of these elements are genotoxic, yet they have a profound effect on gene expression.…”

“…Lead was associated with lower birth weight, accelerated growth in early childhood, and prehypertension. These are all early indicators of cardiometabolic syndrome in childhood …”

“…From these new technologies, we have discovered that 2 of these xenobiotics, lead and cadmium, are found together in humans about 50% of the time. 39 Neither of these elements are genotoxic, yet they have a profound effect on gene expression. This has led to the hypothesis that both are modifying the epigenome.…”

“…These are all early indicators of cardiometabolic syndrome in childhood. 39,40,42 So what do you do when you have association results? The possibility of confounding by difficult-to-measure, nonchemical stressors that co-occur with poverty and ethnic minority status makes it very difficult to advocate for a policy to reduce exposure, since cause and effect is difficult to infer.…”

Placental adaptations to micronutrient dysregulation in the programming of chronic disease

“…In contrast, iron supplementation has been shown to increase maternal risk of developing GDM, possibly through oxidative stress mechanisms . A recent study has linked non‐essential metals including cadmium, lead and arsenic to essential trace elements including iron, zinc, selenium, copper, calcium, magnesium and manganese, showing a negative dose‐dependent interaction, mitigating function of essential trace elements which is associated with low birthweight . This exemplifies the contraindications of micronutrient interactions which may have implications for individuals exposed to environmental toxins or those that take micronutrient supplements leading to unnecessary excessive levels of micronutrients.…”