Du et al. 2025 — Heavy metal exposures in infants with reflux or dysphagia using different thickeners

This study assessed heavy metal exposures specifically in infants with reflux or oropharyngeal dysphagia who use thickeners as medical treatment. Fifty-six infants under one year of age at Boston Children’s Hospital submitted urine samples and 3-day dietary recalls. Three thickener groups were compared: commercial gel-based thickener or purees (control, n=27), anti-reflux formula (n=19), and infant oatmeal/rice cereal (n=10). ICP-MS with arsenic speciation measured 22 elements in urine including iAs, Pb, Hg, Cd, Sn, Cr, Ni, and U. Urinary arsenic (total and speciated iAs) did not differ significantly between thickener groups (p=0.086); all values were well below the ATSDR toxicity threshold of 100 µg/L. Only molybdenum showed significant differences between thickener groups after Bonferroni correction (p=0.0012, higher in oatmeal/rice cereal group). The number of servings of alternative arsenic dietary sources (applesauce, carrots, sweet potato) predicted higher urinary arsenic (p=0.001).

Key numbers

56 infants (mean age 7.0 ± 2.8 months). Median total urinary arsenic: oatmeal/rice cereal group 1.78 µg/L; anti-reflux formula group 0.96 µg/L; control thickener/purees group 0.76 µg/L; p=0.086 (not significant). All urinary arsenic values below 100 µg/L (ATSDR threshold). 22 elements measured; significant between-group differences found for 9 elements (Be, Mn, Fe, Mo, Cd, Sn, Sb, Hg, Pb) but only Mo survived Bonferroni correction. Urinary concentrations in ranges consistent with the New Hampshire Birth Cohort Study reference values. ICP-MS speciation: estimated total arsenic = sum of arsenite + arsenate + MMA + DMA (arsenobetaine excluded).

Methods (brief)

Spot urine collected on day 3 of 3-day dietary diary. ICP-MS with LC-ICP-MS for As speciation. Urine reference materials/quality-certified standards were run after each calibration and every 20 samples. No creatinine adjustment (validated as appropriate per cited literature). IRB approved: Boston Children’s Hospital (11/12/2021, IRB-P00039551).

Implications

Certification: Key finding: urinary arsenic in infants using rice/oatmeal thickeners was not significantly elevated above controls, and all values were below the ATSDR threshold cited by the authors. Use as clinical biomonitoring context for infant cereal exposure, not as a standalone safety determination for infant cereal or formula categories. Courses: Important for infant exposure assessment module; demonstrates that dietary diversity (applesauce, carrots, sweet potato) is a stronger predictor of urinary arsenic than thickener type. App: Urinary biomarker data can inform qualitative context for infant cereal exposure, while preserving the study’s limited clinical cohort and nonsignificant arsenic-group comparison. Microbiome: Infant exposure data relevant to early life metal exposure and microbiome development context.

Wiki pages this source may touch

• infant-cereal
• baby-cereals-dry-rice-based
• rice
• oat
• arsenic-total
• arsenic-inorganic
• lead
• mercury-total
• cadmium
• tin
• chromium
• nickel
• uranium

Verification notes

• Cross-vendor strict Part 12 recheck 2026-05-17 removed product brand names used as thickener-group identifiers, corrected invalid formula/product and matrix vocabulary, removed non-taxonomy health wikilink, removed instrument/reference-material brand names from Methods, and tightened HMT&C/app language away from safety determinations.

Page history

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