Muchas personas consumen sin saberlo grandes cantidades de arsénico disueltas en el agua, lo que puede provocar graves trastornos.

Según un estudio, realizado en Tailandia y publicado en 'PLoS Genetics,' esta exposición puede afectar incluso al bebé durante la gestación. Sus conclusiones muestran que los niños expuestos al arsénico dentro del útero materno presentan cambios en la expresión de algunos genes. Esto podría favorecer la aparición de cáncer y otras patologías, según sugiere la investigación.

Mathuros Ruchirawat of the Chulabhorn Research Institute in Thailand and Leona D. Samson of the Massachusetts Institute of Technology in Boston said the study involved 32 mothers and their children in a province of Thailand that experienced heavy arsenic contamination from tin mining. The researchers said similar levels of arsenic are found in many other regions, including the U.S. Southwest.

The research team analyzed blood collected from umbilical cords at birth, while the mother's exposure to arsenic during their pregnancy was independently determined by analyzing toenail clippings.

The team found a collection of about 450 genes that had been turned on or turned off in babies who had been exposed to arsenic while in the womb -- the genes had become significantly more active or less active than in unexposed babies.

The study, published in the journal PLoS Genetics, found gene expression changes found in the exposed children are mostly associated with inflammation, which can lead to increased cancer risk.