Can arsenic in food and water during pregnancy cause low birth weight and preterm birth?

What's actually in it

Inorganic arsenic enters the food supply mainly through rice (which accumulates arsenic from soil and water more efficiently than other grains), rice-based baby cereals, apple juice from orchards near old pesticide use, and some ground and surface water sources. Pregnant people in the US have measurable arsenic levels from these dietary sources.

Arsenic disrupts placental function, restricts blood flow to the fetus, and causes oxidative stress in fetal tissue. These mechanisms directly affect fetal growth and can trigger early delivery. Low birth weight and preterm birth are among the strongest predictors of infant health complications and long-term developmental outcomes.

What the research says

A 2026 meta-analysis in Environ Res pooled data from multiple studies on arsenic exposure and birth outcomes. Higher arsenic exposure was significantly associated with lower birth weight, higher preterm birth rates, and higher rates of small-for-gestational-age. The meta-analysis also calculated benchmark doses, estimating the arsenic levels at which these risks begin to increase.

The benchmark dose analysis found risks increase at arsenic concentrations within the range measured in many US pregnant women, not just in areas of extreme industrial contamination.

For pregnant people, the main dietary arsenic reduction steps are: limiting rice consumption (or choosing lower-arsenic varieties like basmati from California, or switching to other grains), avoiding rice-based baby cereals (oat-based has less arsenic), and testing drinking water if on a private well. Apple juice has lower arsenic than rice but should also be limited in pregnancy.