Canon has issued a warning to owners of the EOS 650D/Rebel T4i that the rubber hand-grips of some models may turn white, and produce a chemical that can cause an allergic reaction. According to Canon, the chemical, zinc bis (N,N’-dimethyldithiocarbamate), is not used in the production of the camera but is a potential by-product of a chemical reaction between other substances found in the hand-grip. Canon has identified a certain number of cameras where a larger than normal amount of 'rubber accelerator' was used in the production of this component, which could potentially cause this chemical reaction.

Canon has set up a website where you can check whether your model is affected. Click on this link and enter the serial number of your camera, and the site will let you know whether your camera is from the affected batch.

The hand-grips of some EOS 650D/Rebel T4i cameras may become discolored due to a
chemical reaction caused by substances used in their manufacture (image: Canon Inc.)

According to Canon USA, 'some EOS 650D/Rebel T4i cameras' manufactured between May 31st and June 15th 'may be affected' by this chemical reaction, which causes the hand-grips of the cameras to turn white. Zinc bis, the substance produced by the chemical reaction, may cause an allergic reaction in some people, and 'as a precautionary measure' Canon advises owners of affected cameras to 'thoroughly wash your hands with water if they have come in contact with the rubber grip'.