Vapers who use nicotine-free e-cigarettes are potentially inhaling not only nicotine but also trace amounts of pesticides and a biological chemical found in urine and faeces, an Australian study has found.

WA researchers purchased 10 different e-liquid products labelled ‘nicotine-free’ from Australian suppliers and had their chemical composition analysed by an independent commercial laboratory.

Nicotine was detected in six of the e-liquids, including three that had levels comparable to those found in low-dose nicotine e-cigarettes.

Lead researcher Associate Professor Alexander Larcombe, from the Telethon Kids Institute and Curtin University in Perth, said nicotine contamination was the inevitable result of zero regulation in the manufacture of vaping products.