Triclosan et DNA methylation

How can exposure to triclosan, a chemical found in various consumer products, affect the functioning of certain genes?

Triclosan is a chemical present in various consumer products such as personal care products, cleaning products, and certain plastics. It possesses hormone-disrupting properties, meaning it can mimic, block, or interfere with hormone action. This property, combined with its widespread presence in the environment, raises health concerns.

What is DNA methylation?

DNA methylation is a chemical process that occurs within cells. During this process, molecules called "methyl groups" are added to the DNA. These modifications influence how certain genes function: some genes will be more strongly expressed while others will be less expressed. This process can be compared to a sheet music played by an orchestra: the DNA is the sheet music that has been written, it does not change. DNA methylation corresponds to the interpretative work that the orchestra performs by adding certain marks of accentuation or attenuation to the score. This interpretation can vary each time with notes more or less emphasized, depending on who is playing the sheet music and how it is played.

Measurement of triclosan and DNA methylation

In the SEPAGES study, triclosan was measured in urine collected during pregnancy. After childbirth, small pieces of placenta were collected by maternity staff. Using advanced techniques, information about the amount of DNA methylation present in the placenta was obtained from these placenta samples.

What effect does triclosan have on DNA methylation?

The results of our study suggest that exposure to triclosan during pregnancy is associated with an increase in placental DNA methylation, particularly in genes related to fetal and placental growth. An increase in placental methylation could disrupt gene activity and have repercussions on the proper development of the placenta and fetus.
These results help to better understand how environmental exposures during pregnancy may influence fetal development.

What’s next?

Further research is needed to better understand:

• 1) the long-term consequences of triclosan exposure on fetal development and child health in adulthood
• 2) the precise role that alterations in placental DNA methylation play in fetal and child health.