"concerns have grown" is a correct and usable phrase in written English.
It can be used to describe an increase in worries on a particular issue. For example, "Concerns have grown about the environmental impact of factory farming."
Concerns have grown of an accidental confrontation that could escalate.
Concerns have grown about trading firms getting early peeks of certain releases.
But as more birds have been discovered with the virus, concerns have grown.
As her business has flourished, Ms. Nelson's environmental concerns have grown.
However, concerns have grown that the freedom from annuities will create a new mis-selling scandal.
Those concerns have grown recently, as Iran has begun to move some uranium enrichment to a more secure location.
The report was requested by the Department of Education, where concerns had grown because of the increasing number of children with autism coming into public school systems.
Mr. DiNizio, who wore a blue blazer but no tie, said his political concerns had grown along with his 6-year-old daughter, Liza.
Alston, who teaches law at New York University, noted in his statement to the United Nations that the urgency of his concerns had grown "dramatically in importance," because of the escalating pace of U.S. drone strikes.
As awareness of environmental concerns has grown, therapists say they are seeing a rise in bickering between couples and family members over the extent to which they should change their lives to save the planet.
The spending and tax measure has become caught up in intensifying politics around deficit spending as members of both parties, reacting to rising public concern, have grown reluctant to vote for measures that add to federal red ink.
