Scented candles—especially paraffin-based—don’t just smell cozy. Multiple studies show they release toxic chemicals like benzene, formaldehyde, toluene, carbon monoxide, and polycyclic aromatic hydrocarbons (PAHs)—many of which are carcinogenic, hormone-disrupting, or linked to respiratory disease.

New research reveals that car air fresheners—especially tree-shaped ones like Little Trees—emit dangerous chemicals such as VOCs and phthalates, which have been linked to respiratory issues, hormone disruption, reproductive problems, and even cancer. In a confined space like a car, exposure can be intense and long-lasting.