Concerns grow as the pueblo county inmate search site goes offline

To express a concern or express concerns is using the word in its countable noun sense, which refers to one or more specific concerns - a concern being particular element or thing to be concerned about. So you might say: I have one or two concerns with this proposal. However, there are concerns that they[certain drugs] could pose a serious health risk to humans. However, there is concern that they[certain drugs] could pose a serious health risk to humans. H... singular vs plural - "there are concerns that" VS "there is concern ... Commercial builders downplayed ______ a bust in the superheated housing market. 1) The concern of 2) Concerns about The answer is number 2, but why does number 1 not work? Since I know for a fact that the concerns are not "raised by many fish oil brands", shouldn't 'raised' come right after 'concerns'?: They are free of the concerns raised about impurities and odor by many fish oil brands. I googled "concerns raised about", and it's been used and seems correct. So is the original sentence correct?

For @Billy Kerr :‘Bob or Sarah have any concerns’ is not an exception; it is non-standard/informal usage in conversation. In teaching/learning settings or in writing it is not acceptable.