If it's true that household cleaning products cause cancer, why aren't there any warnings on the labels? I am worried for my family."

In Australia, chemicals used in household cleaning products are examined for safety by a federal government agency known as NICNAS (the National Industrial Chemicals Notification and Assessment Scheme). They are responsible for advising state and territory government regulators on the safety of industrial chemicals used in Australia. 

The labelling of chemicals that are potentially harmful is based on a system known as “scheduling”. In general, industrial chemicals with higher potential to cause harm, including cancer, are placed in schedule 6 or 7 and would not be permitted to be used in household products. The chemicals used in household products are generally of low toxicity and there is no evidence they cause cancer. They still have the potential to cause harm, for example through accidental poisoning in children or if used incorrectly. 

Products come with instructions for use to avoid incorrect use, are packaged appropriately to minimise exposure, warning labels are present when necessary and you should store your products securely away from children.