Measurement / residue studyindependent cross-checkabstract checked★ key study I-GRN-116 in-depth review

Half a cup of rice a day adds arsenic like drinking water at the legal limit

Rice consumption contributes to arsenic exposure in US women.

Overview

Gilbert-Diamond D et al.. Proc Natl Acad Sci U S A 2011 · PMID 22143778 · DOI 10.1073/pnas.1109127108

In 229 pregnant women, rice intake raised urinary arsenic; 0.56 cup of cooked rice per day matched 1 L of water at 10 ug/L.

Does the study support the specific claim? No · Methodological quality: moderate

Study explained simply

What did the researchers want to find out?: Measure rice as arsenic source.
How was the study done?: Urine tests and diet records.
How many people, animals or samples were studied?: 229 pregnant women.
What was actually found?: Rice raised arsenic levels.
How large was the observed effect?: Equivalent to 1 L/day of water at the limit.
What do the results mean in everyday life?: Rice is a real arsenic source.
What are the study's limitations?: No health outcomes.
What does it say about Elawady's specific claim?: Contradicts dismissing arsenic concerns.
Do the results apply to Germany and Europe?: Moderate.
What can explicitly not be concluded from this study?: Does not show disease from rice.

Authors: Gilbert-Diamond D et al.
Journal: Proc Natl Acad Sci U S A
Year: 2011
Identifier: PMID 22143778 DOI 10.1073/pnas.1109127108 · PMC3251121
Verification: verified – PubMed efetch 2026-10-26; Crossref works API 2026-10-26
Retracted: no
Corrections: none
Extent checked: abstract only
Conflicts of interest and funding: No conflicts declared; NIH grants

Does rice consumption contribute to arsenic exposure in pregnant women?

Study design: Measurement / residue study – Cross-sectional biomarker study within a pregnancy cohort
Population: Pregnant women in a US cohort
Country: USA
Period: not stated in abstract
Sample size: 229
Inclusion and exclusion criteria: Urine sample and 3-day diet record at 6-month prenatal visit

Results: Rice and water arsenic both associated with ln total urinary arsenic (beta rice 0.009 per g/day, beta water 0.028 per ug/day; both P<0.0001) and with inorganic, MMA and DMA. 0.56 cup/day cooked rice was comparable to drinking 1 L/day of water at the US limit of 10 ug/L.
Absolute risks: not reported
Authors' conclusion: Rice consumption should be considered when designing arsenic reduction strategies.

Recalculated equivalence: about 31 g dry rice/day equals 1 L/day of 10 ug/L water (stats/C-GRN-06).

Shows rice measurably increases arsenic exposure, contradicting the claim that concerns are unfounded.

Exposure is not harm; I-GRN-115/I-GRN-118 found no CVD or clear cancer link at US intakes.

Moderate.

Solid exposure evidence.

Multidimensional assessment
Multidimensional assessment
Authenticity of the source	verified
Methodological quality	moderate
Risk of bias	some concerns
Precision of results	moderate
Directness	direct
Reproducibility	replicated
Consistency with the overall evidence	consistent
Regional transferability	moderate
Adequacy of the interpretation (by the archive)	not applicable

Exposure from Egyptian rice.