Phosphonates are of low to moderate toxicity to people. If phosphonates are ingested, they are not easily absorbed by the digestive system and are rapidly eliminated from the body via faeces. Intake through the skin is also unlikely to cause harm due to the low potential for phosphonates to accumulate in the body.

There are no toxicity or eco-toxicity issues for phosphonates used in consumer detergents. These products contain extremely low concentrations of phosphonates which are unlikely to cause harm. This has been confirmed through multiple tests and studies which are documented in the REACH dossier for each compound.

Phosphonic acids can be a moderate to severe eye irritant/corrosive. Neutralised products show only a slight irritating potential. It should be noted that the irritant or corrosive properties of aqueous phosphonic acid solutions are mainly caused by inorganic acid formed as by-products in industrial processes.