Police say Edward Vargas was arrested Thursday morning.
He allegedly got into a fight with the victim because she wouldn't let him use her cell phone.
Then she says he sprayed her and her 11-month-old daughter with a substance that irritated their eyes and made it hard to breathe.
Vargas has been charged with two counts of assault.
The mother spoke exclusively to Eyewitness News about her ordeal shortly after being released from a hospital in Astoria.
The 25-year-old mom said she briefly interacted with the man who would later attack her when they were on the platform of the 36th Street station.
She says the man asked to borrow her phone and she declined.
When the M train they boarded arrived at the Court Street 23rd Street station in Long Island City, the man out of the blue attacked her and her 11-month-old daughter with what she believed to be pepper spray.
"A guy just came out of nowhere, and he throws the pepper spray to me and my child," the mom said.
The mother and daughter were treated at Mount Sinai Queens and released a few hours later.
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