Yes, it is true...
the chemical called Bisphenol used to make clear, hard plastic bottles kind of leeches out every time you use and reuse the bottle....so be very careful with what type of bottle you use...usually bottles with a grade of more than 5 are considered safe. All others can put you into a health risk....
You can check the bottle simply by cheking the bottom where a number is embossed....it may range from 1-7 and anything equal to 5 or above is safe.