Content and Dietary Exposure Assessment of Toxic Elements in Infant Formulas from the Chinese Market

Key Numbers

Metal	N Samples	Range (µg/kg)	Mean (µg/kg)	Std Dev	Domestic Mean	Imported Mean
Pb	93	0.36–5.57	2.07	1.59	1.48	2.37
Cd	93	0.13–3.58	1.21	0.94	0.80	1.43
tAs	93	0.89–7.87	3.53	2.08	2.95	3.86
Cr	93	2.51–83.80	32.95	25.41	24.07	37.81

Regulatory Comparison

Jurisdiction	Analyte	Limit	Regulatory Body	Chinese Formulas Median	Exceedance
China	Pb	150 µg/kg	National standard GB 10765	2.07 µg/kg	None
EU	Pb	50 µg/kg	Commission Directive 2006/141/EC	2.07 µg/kg	None
CAC	Pb	10 µg/kg	Codex Alimentarius	2.07 µg/kg	None
EU	Cd	10 µg/kg	Commission Directive 2006/141/EC	1.21 µg/kg	None

Risk Assessment: Target Hazard Quotient (THQ)

Metal	THQ Range	Max THQ	Acceptable Threshold	Status
Pb	0.00–0.45	0.45	<1.0	Safe
Cd	0.00–0.38	0.38	<1.0	Safe
tAs	0.00–0.28	0.28	<1.0	Safe
Cr	0.00–0.22	0.22	<1.0	Safe

Hazard Index (HI, sum of all THQs) ranged 0.00–0.98; all <1.0, indicating no non-carcinogenic risk from combined chronic exposure.

Methods

Study enrolled 93 infant formula samples purchased from markets in Beijing, China: 27 domestic products and 66 imported formulas. Samples stratified by feeding stage (stage 1 for 0–6 months: n=28; stage 2 for 6–12 months: n=27; stage 3 for 1–3 years: n=24; stage 4 for 3–6 years: n=14). Analysis by inductively coupled plasma mass spectrometry (ICP-MS) following sample digestion in high-purity nitric acid (microwave digestion, 180°C, 60 minutes).

Dietary exposure quantified as estimated daily intake (EDI) computed from measured metal concentration × average daily consumption for each feeding stage (per Chinese dietary guidelines). Risk assessment applied Target Hazard Quotient (THQ) methodology: THQ = (EDI × exposure frequency × exposure duration) / (reference dose × average body weight). Carcinogenic risk not addressed (carcinogenicity classification of these metals not standardized in Chinese regulatory framework at publication date). Statistical analysis included descriptive statistics, comparison of domestic vs. imported formulas (t-test), and stage-stratified analysis.

Implications for Heavy Metal Index

This source documents measured total-arsenic (tAs) occurrence and chromium (Cr) occurrence in a major feeding-stage-stratified survey of both domestic and imported infant formulas sold in China. All measured values fall well below applicable regulatory limits (China, EU, CAC). Risk assessment via THQ methodology found no non-carcinogenic concern from chronic dietary exposure to measured metals at observed concentrations. Study does not distinguish inorganic arsenic (iAs) from total arsenic; values reported as tAs and should be annotated as such in contamination profiles.

Cr speciation (total Cr vs. Cr-VI) not determined; measured Cr should be stored as total chromium.

Update history

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Commit	Date	Change	Description
bc84bfc	2026-08-02	major	7 sections added; narrative text revised