Prenatal nonessential metals may contribute to postnatal adiposity, whereas essential metals may have metabolic benefits. We evaluated joint and individual associations between prenatal metals and childhood adiposity.
We measured concentrations of six nonessential (arsenic, barium, cadmium, cesium, lead, and mercury) and four essential (magnesium, manganese, selenium, and zinc) metals in first trimester maternal blood from a prebirth cohort. We collected anthropometric measures in early childhood, mid-childhood, and early adolescence including subscapular+tricep skinfold thickness (mm) (N = 715–859), waist circumference (cm) (N = 717–882), and body mass index (BMI) (z-score) (N = 716–875). We measured adiposity in mid-childhood and early adolescence using bone densitometry total- and trunk- fat mass index (kg/m2) (N = 511–599). We estimated associations using adjusted quantile g-computation and linear regression.
The nonessential metal mixture was associated with higher total (β = 0.07, 95% CI = 0.01, 0.12) and trunk fat mass index (β = 0.12, CI = 0.02, 0.22), waist circumference (β = 0.01, CI = 0.00, 0.01), and BMI (β = 0.24, CI = 0.07, 0.41) in mid-childhood, and total fat mass index (β = 0.07, CI = 0.01, 0.14), and BMI (β = 0.19, CI = 0.02, 0.37) in early adolescence. The essential metal mixture was associated with lower early adolescence total-(β = –0.11, CI = –0.17, –0.04) and trunk- fat mass index (β = –0.13, CI = –0.21, –0.05), subscapular+tricep skinfold thickness (β = –0.02, CI = –0.03, –0.00), waist circumference (β = –0.003, CI = –0.01, –0.00), and BMI (β = –0.16, CI = –0.28, –0.04). Cadmium and cesium were individually associated with childhood adiposity at different timepoints.
Prenatal first-trimester essential metals were associated with lower childhood adiposity, whereas nonessential metals were associated with higher adiposity into adolescence.