Fake perfumes aren't just a problem for the company that makes them legally, either. "In addition to the economic harm," Customs said in its statement, "counterfeit perfumes are also often contaminated with unknown chemicals that can cause serious injury." There's no regulation on this stuff, and tests have found some truly heinous ingredients, from urine to known carcinogens. So when it comes to perfume, you're almost always better off biting the bullet and paying full price at the department store. Carrie wouldn't tolerate a knockoff, and neither should you.