Since spotify has replaced rdio the problem of explicit songs has become a bit of a problem. I can't listen to recommended playlists without coming across explicit songs, and spotify dose not have a filter like other services such as Google Play, iTunes and Pandora.
It is a well know problem in spotify since 2012 but spotify has still not responded. Perhaps Tesla can help persuade Spotify to implement an explicit filter as it is a huge problem listening to Spotify in the car with children.
below is a link to spotify community forum detailing the issue