Politico reports Congressmen Ed Markey (D-Mass.) and Joe Barton (R-Texas) are sending another letter to Facebook today concerned about privacy issues. The two fired off a letter last fall after the Wall Street Journal reported third party apps on the site were collecting all kinds of user information. Now, they're wondering why Facebook introduced a feature earlier this year that would allow developers and websites to access users' phone numbers and addresses. Facebook has removed the feature after getting heat for it in January, but the company says it will re-enable the feature once it can figure out how to tell users their data is being shared. So, Markey and Barton want to know, "Why is Facebook, after previously acknowledging in their November 3 response to our October 19 letter that sharing a Facebook User ID could raise concerns, subsequently considering sharing access to even more sensitive personal information such as home addresses and phone numbers to third parties? And did they take into account possible risks to children and teens?"