The effects of Nicotine/second-hand smoke on the developing human brain

Research the effects of Nicotine/second-hand smoke on the developing human brain. Research on this topic should include scientific evidence supporting the associations between Nicotine/second-hand smoke and the effect is actually has on the human brain. To investigate the associations (often aims causal relationships), you will have to explain how someone would we exposed to the substance and the characteristics of the health effects.