Frances Kelly claimed, magnetic putty - which contains a bag of putty and a small cube magnet - made her daughter sick.
Writing on Facebook, Frances wrote: “We have received shocking news this afternoon with the results of my daughter Neve’s tests and there is a toxicology team in Edinburgh who are now dealing with it there were 10 times the normal level of arsenic found in her urine.
“They had to take vials of blood and get it sent to the arsenic specialist in Glasgow.
“They’re all in shock this should be on the news he said he couldn’t believe it Neve has thankfully not shown many symptoms of damage and pray this test will be lower as she hasn’t been in contact with it since January.
“If we hadn’t found out when we did pray to God her tests will be all clear.
“So please if you have this product get your children tested.”
Arsenic is a highly toxic chemical that can lead to cancer after long-term exposure.
Frances has since reported that Neve is recovering.
Last month, Northamptonshire Trading Standards barred the putty from sale after discovering it on a market stall.
They said, a magnet included in the banned toy, which has no manufacturer or importer identification, was found to be 29 times over the allowed magnetic force and could be “easily swallowed”.