Foetal exposure to heavy metals and risk of atopic diseases in early childhood

Abstract

Background Accumulating evidence suggests that in utero exposures can influence the development of the immune system and thus contribute to disease development. Studies investigating the association between prenatal exposures to heavy metals and atopic diseases, however, are scarce. Methods Children from the EDEN birth cohort were prospectively followed up using parental questionnaires with validated questions on asthma, allergic rhinitis, eczema, and food allergy symptoms. The questionnaires were administered every 4 months during the children's first year, and then every year until the age of 5, with a final survey at the age of 8. Serum concentrations of lead (Pb), cadmium (Cd), and manganese (Mn) were assessed in maternal blood samples collected during mid‐pregnancy and in cord blood of 651 mother‐children pairs. Hazard ratios (HR) for the incidence of each atopic disease in relation to the exposure to metals were calculated using Cox proportional hazard models. Results Levels of Cd in cord blood were associated with greater risk of asthma (hazard ratio [95% confidence interval] for upper vs lower quartile: 1.81 [1.00‐3.29]), eczema (1.60 [1.09‐2.35]), and food allergy (3.17 [1.36‐7.38]), while Mn levels in maternal serum were associated with eczema (1.55 [1.05‐2.28]). These associations were similar in males and females and were confirmed using log concentrations of metals as exposures. Conclusions Our results support the hypothesis that fetal exposure to heavy metals may affect the development of asthma, eczema, and food allergy in childhood and suggest that timing of exposure in utero may have a role in these associations.

Nutritional epigenetics education improves diet and attitude of parents of children with autism or attention deficit/hyperactivity disorder

“…Emerging evidence suggests prenatal exposure to heavy metals can influence the development of the child’s immune system and contribute to the development of various disease conditions[ 20 ]. Prenatal exposures to cadmium (Cd), Pb, and/or Hg have been linked to the development of asthma, eczema, food allergy, and adverse respiratory outcomes in children[ 20 - 22 ]. Heavy metals may be transmitted to the fetus during pregnancy via cord blood.…”

Prenatal dietary exposure to mixtures of chemicals is associated with allergy or respiratory diseases in children in the ELFE nationwide cohort

“…Some epidemiologic studies have reported an increased risk of allergies or asthma in children born to mothers exposed to some environmental chemicals during pregnancy, such as pesticides [ 13 ], perfluoroalkyl acids (PFAAs) [ 44 ], phthalates [ 63 ], trace elements (TE) [ 50 ], polycyclic aromatic hydrocarbons (PAHs) [ 34 ], bisphenol A (BPA) [ 68 ], brominated flame retardants (BFRs) [ 42 ] or polychlorobiphenyls (PCBs) [ 46 ]. Inversely, other studies found a decreased risk of allergy or wheezing related to the prenatal exposure to some PFAAS [ 2 ], pesticides [ 41 ], BFRs [ 43 ], and BPA [ 19 ].…”

Exposomic determinants of immune-mediated diseases

“…Development of preventive interventions requires profound understanding of the disease mechanisms, including key molecules and pathways. Based on the current consensus, these mechanisms operate already at early life including the in utero period, 15 , 16 when the first subclinical signs of IMDs often appear 17 and when the immune system is under rapid transition from an immature stage to the mature adult stage. As a significant component in these processes, the crosstalk between the commensal microflora 18 , 19 and the child’s maturating immune system has received special attention in the field.…”