"The "Magnetic Putty" toy was banned from sale by Northamptonshire Trading Standards (NTS) who found it had seven times the permitted amount of arsenic.
Amazon, eBay and Groupon all removed the toy, which has no manufacturer or importer identification, from sale.
Last week a schoolgirl reportedly had 10 times the safe limit of arsenic in her system after playing with the toy.
NTS discovered the toy on a market stall in the county and, as well as a high level of the poison, the included magnet was found to be 29 times over the allowed magnetic force and could be "easily swallowed"."