Bordbar was among 17 political prisoners who have reportedly been on hunger strike since late last month to protest against the worsening conditions at Tehran's Evin prison.
Bordbar's photos landed him in prison after the mass postelection protests last June.
On August 6, Human Rights Watch called on Iran to end the solitary confinement of prisoners and grant them all the protections to which they are entitled, including access to their families and lawyers.
There is growing concern about the health of the prisoners who have refused to eat since July 26. Three of them, journalists Bahman Amouee and Keyvan Samimi and well-known student activist Majid Tavakoli, are reportedly on a "dry" hunger strike, meaning they refuse to eat or drink.
Opposition leaders Mir Hossein Musavi and Mehdi Karrubi and a number of other political figures have called on the prisoners to end their hunger strike.
A relative of one of the prisoners on hunger strike told RFE/RL that officials have told the family, "It's not our problem your child refuses to eat and drink."
-- Golnaz Esfandiari