One person was been taken to hospital as a precaution after toxic chemicals were dumped at a refuse and recycling centre in the Auckland suburb of Avondale today.

The concentrated nitric acid began smoking and giving off toxic fumes after it was dumped among rubbish at the EnviroWaste refuse and recycling plant in Patiki Rd.

Firefighters, including the hazardous materials appliance crew, went to the centre to neutralise the acid.

EnviroWaste Services Limited said about 6.15am a commercial waste collector deposited a load of refuse at the plant.

ESL staff noticed what appeared to be smoke emitting from the load.

In accordance with emergency operating procedures, using a wheel loader they removed the pile from the general refuse mass to prevent a fire spreading.

While they were doing that the particular waste pile began to emit fumes which staff identified as being a chemical reaction rather than smoke.

Emergency services were immediately called and controlled the emission, closing the site.

The operator of the wheel loader was temporarily exposed to the fumes and was taken to hospital as a precaution. He has since been discharged.

EnviroWaste's specialist hazardous waste handling division, Chemwaste, was also deployed to remove any contaminants.

No member of the public was involved in the incident and the site was re-opened at around midday.

The company said that people who continued to dispose of potentially hazardous chemicals within their general refuse were acting irresponsibly and illegally, endangering people's lives.