Children could become fat if their mother used antibacterial soap during pregnancy, a new study warns.
Full of one toxic chemical, scientists found exposure to the contaminant in the womb can make youngsters obese.
In studies on mice, they showed female offspring to weigh 11 per cent more. Males were 8 per cent heavier on average.
The chemical, called triclocarban (TCC), is passed through both the placenta and through breastfeeding, trials suggest.
Researchers at Lawrence Livermore National Laboratory, California, said everyday exposure could also lead to 'irreversible' damage in vital organs.
Scientists found exposure to antibacterial soaps in the womb can make youngsters obese
TCC, which is also used in the medical field, interferes with lipid metabolism - slowing the body's natural breakdown of fat.
'A serious health risk'
Lead author Dr Heather Enright said: 'We demonstrated that TCC does effectively transfer from mother to offspring, both trans-placentally and via lactation.
'Exposure to TCC during development may pose a serious health risk to the developing embryo and fetus.
'They are more sensitive to alterations in hormone levels, which may result in changes that often are irreversible.'
She continued: 'Our results are significant because of the potential risk of exposure to TCC through contaminated water sources and in the living environment.
'Early life exposure has the potential to cause irreversible outcomes due to the fragile nature of organ systems and protective mechanisms in developing offspring.'