1080 and tap water
Introduction
1080 operations have never contaminated drinking water in New Zealand.To ensure our drinking water is always safe, the Ministry of Health has set a stringent guideline that 1080 can only be present at levels below 2 parts per billion (ppb). This is the equivalent of about 3 pin heads on a football field.
At these extremely low levels, an adult weighing 70 kg would have to drink 70,000 litres (or 230 bath-fulls) in one go to receive a fatal dose.
No tests of drinking water after 1080 operations have ever come close to this limit. For the 1299 samples of water used for human or stock drinking supplies tested between 1990 and 2016, only 5 contained traces of 1080. These had 1080 residues ranging from 0.1 to 0.2 ppb. No 1080 was found in the other samples.
Research into 1080 and water
There is no evidence that drinking water has ever been contaminated with 1080. (To be classed as contaminated, drinking water has to contains 2 or more ppb of 1080.) Extensive research and monitoring in water catchments that have been treated with 1080 show that contamination is highly improbable when the current safety procedures are followed.
Safeguards
Every aerial 1080 operation is strictly controlled and must be approved by a medical officer of health or health protection officer before it can go ahead. This approval can include conditions on the use of 1080.
Conditions can include:
- excluding particular areas to protect drinking water supplies
- requiring bait-free buffer zones around larger streams
- water monitoring after the operation.
If water monitoring is required, samples are collected 12–24 hours after an operation, since this is the time when any of the toxin is most likely to be found. Samples are collected by local or regional councils at sites chosen by a local public health officer. The sampling sites are deliberately chosen to detect any 1080 that has entered the water supply area.
As an extra safeguard, water intakes in an area are often shut down before a 1080 operation until tests confirm the water is completely safe to drink.
Private water supplies
Private water supplies (like streams or rainwater tank supply) are identified as part of the planning for every 1080 operation. Actions to make sure these water supplies stay safe for people are included as conditions that are required to be met when permission for a 1080 operation is given.
Consultation with landowners and iwi is part of planning 1080 operations. Anyone carrying out a 1080 operation is also required to notify all landowners and neighbours about an operation before it happens.
Tramping huts
Exclusions and checks are used to ensure that 1080 does not reach water tanks in back-country huts. Water supplies to huts in 1080 operation areas are closed off until any risk of 1080 being present has passed.
1080 and human health
The tight regulations around the use of 1080 mean that people should not come into contact with 1080 and that drinking water supplies are safe.
The same chemical (fluoroacetate) that is used in 1080 pellets to kill pests, is in a cup of tea. The tea plant, and many other plants, naturally produce this toxic chemical to stop them from being eaten by animals. At the very low levels found in a cup of tea, however, the 1080 toxin is completely harmless.
1080 does not stay (bioaccumulate) in your body, but is quickly broken down and excreted. It is not a hormone or endocrine disrupting chemical and is highly unlikely to cause cancer. When applied safely, 1080 has no long-term effects on human health.
Water testing
In New Zealand, Manaaki Whenua Landcare Research tests water for 1080 using standard protocols and a sensitive gas chromatography method. The method is accredited with International Accreditation New Zealand under Environmental Monitoring.
References
- Water safety after a 1080 drop (NIWA)
- Protocols for water testing (Landcare research)
- Issuing Permissions for Vertebrate Toxic Agents (VTAs): Guidelines for Public Health Units (Ministry of Health)
- Human exposure to fluoroacetate in tea and edible plants – could it exceed acceptable intake limits? (Landcare Research)