California EPA report on secondhand smoke. Extremely detailed and documented. OEHHA protects public health and the environment by scientific evaluation of risks posed by hazardous substances.

Secondhand Smoke Can Make Children Suffer Serious Health Risks. Breathing secondhand smoke can be harmful to children's health including asthma, Sudden Infant Death Syndrome (SIDS), bronchitis and pneumonia and ear infections.

Report from the Washington Post. Most scientific studies in recent years support the point: Breathing someone else's tobacco smoke can hurt one's health.

Internal Documents Prove Tobacco Industry Aware of Second-Hand Smoke Risks, Researchers Say. Internal documents show the tobacco industry knew about but consistently failed to warn people about the health risks from second-hand smoke.