There’s no way around it — it’s toxic . Cocaine is a powerfully addictive stimulant that can quickly and significantly mess with the heart and the brain. Roughly 25 million people use cocaine worldwide each year, studies show, including an estimated 750,000 pregnant women . There’s new interest in the effects of cocaine on babies following accusations Kevin Federline, 47, lodged against ex-wife Britney Spears, 43, in his exposé, “You Thought You Knew,” due out Tuesday. In the book, Federline