Not that this applies to me at all but sure is something for people/businesses with some exposure online to make sure about.
So a recent example of what being careful what you hashtag is the DiGiorno Pizza brand. https://twitter.com/DiGiornoPizza
One of their social media people made a mistake and hashtagged a domestic violence reference trending topic in a total out of whack stupid context. Not only was it seen but it created a shit storm of bad PR for them. (reference http://mashable.com/2014/09/09/digiorno-pizza-whyistayed-hashtag/)
On the bright-side #1 we are all human and screw-up. And #2 they realize it and are totally taking the appropriate steps to say sorry.
Lesson learned: If people follow you or your brand online make sure before jumping on the “trending” bandwagon to do a tiny-bit of research first.