The phrase "reignited concerns" is correct and usable in written English.
It is often used to describe a situation where worries or fears that had previously subsided have been sparked or renewed. Example: The recent spike in COVID-19 cases has reignited concerns about a second wave of the virus spreading throughout the country.
The news has reignited concerns that Britain is still gripped by a cost of living crisis.
The recent college admissions scandal has, not surprisingly, reignited concerns about overinvolved parents.
The malfunction in Chicago stoked fear again among regulators and reignited concerns about the market's vulnerability to broader shocks.
But the imbroglio also reignited concerns about historic marginalization of trans people within the modern gay rights movement.
With unions announcing a general strike on 4 February, the prospect of social upheaval has reignited concerns over Greece's ability to remain in the single currency.
But one photo, aired by TV station KTVU, has sparked backlash and reignited concerns about the biased portrayal of minorities, particularly African Americans, by news outlets.
But recent studies have reignited concern.
A request by tobacco giant Philip Morris International to the University of Stirling has reignited concern about the use of freedom of information laws.
The shooting reignited concern among public officials and community activists about race relations and stereotypes within the police force.
The Manchester bombing, which followed an earlier terror attack in Westminster, has reignited concern about the easy availability of material promoting violent extremism online.
The underwear bomb that surfaced in Yemen this month has reignited concern that al-Qaeda's bomb-makers are finding innovative ways to hide explosive devices - even placing them within the body.
