Parabens
Also known as: Methylparaben, Ethylparaben, Propylparaben, Butylparaben
Preservatives in cosmetics that mimic oestrogen. Detected in breast tumour tissue.
Why it's harmful
Parabens are esters of para-hydroxybenzoic acid, used as preservatives in cosmetics since the 1920s. They prevent bacterial and fungal growth.
Oestrogenic activity: Parabens bind to oestrogen receptors and mimic the hormone's effects. Butylparaben has the strongest oestrogenic activity — about 1/10,000th the potency of estradiol, but exposure is continuous.
Found in tumours: A 2004 study detected parabens in 18 of 20 breast tumour samples. While this doesn't prove causation, it demonstrates that parabens accumulate in breast tissue.
Absorption: Parabens are absorbed through skin within hours of application. Studies detect them in urine, blood, and breast milk of virtually everyone tested.
Longer chain = worse: Propylparaben and butylparaben have stronger oestrogenic effects than methylparaben. The EU has restricted concentrations of the longer-chain parabens.
Cumulative exposure: The concern isn't one product — it's the combined exposure from multiple paraben-containing products used daily over decades.
Where it's found
- -Moisturisers and lotions
- -Shampoo and conditioner
- -Makeup and cosmetics
- -Sunscreen
- -Shaving products
Why avoid it
Parabens mimic oestrogen and accumulate in body tissue. Continuous daily exposure from multiple products adds up.