Canon is warning consumers that one of its cameras creates an allergic reaction.

Canon worldwide told owners of the Canon EOS Rebel T4i on July 6 that some of the units had been having chemical reactions that resulted in the grip changing colours and which could possibly lead to allergic reactions. Canon Australia issued a statement at about the same time which said that the affected camera - sold as the EOS 650D was not affected.

But now  Canon has admitted that it had "broadened the serial number range of potentially affected products".

Canon is now advising users of EOS 650D cameras who have checked their camera serial number prior to 3 August 2012 to do it again in case their camera gives them red eye. The company has set-up a website for users to check if their camera is affected by the manufacturing fault.

Canon said that the cameras contained a slightly higher amount of rubber accelerator than normal. That in turn was leading to a chemical reaction that created the substance zinc bis, which turns the camera's grips white and which could potentially cause allergic reactions.