California's landmark Proposition 65, the Safe Drinking Water and Toxic Enforcement Act of 1986, was enacted as a ballot initiative in November 1986. The Proposition was intended by its authors to protect California citizens and the State's drinking water sources from chemicals known to cause cancer, birth defects or other reproductive harm, and to inform citizens about exposures to such chemicals. Proposition 65 requires the Governor to publish, at least annually, a list of chemicals known to the state to cause cancer or reproductive toxicity. Products containing chemicals on the Proposition 65 list are required to carry the following warning in California: "WARNING: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm."



The following compounds that are on the Proposition 65 list have already been identified in mainstream or secondhand (sidestream) e-cigarette vapor:



Acetaldehyde (MS)

Cadmium (MS)

Formaldehyde (MS,SS)

Isoprene (SS)

Lead (MS)

Nickel (MS)

Nicotine (MS, SS)

N-Nitrosonornicotine (MS, SS)

Toluene (MS, SS)



As the two papers linked above note, there are other toxic chemicals in the vapor as well as ultrafine particles, that likely have cardiovascular effects. E-cigarettes do not deliver "pure nicotine" and "harmless water vapor."