Dunedin City Council and Public Health South are advising residents in Waikouaiti, Karitane and Hawksbury not to use tap water for drinking, cooking or preparing food until further notice.
The advice was issued on Tuesday, 2 February 2021, after elevated lead levels were detected during recent water sampling.
Water tankers are at several locations in both Waikouaiti and Karitane, so that people have access to clean drinking water. It is still safe to use tap water for bathing, washing hands, dishes and clothes.
If you have stopped consuming the tap water, you are no longer exposed to this potential source of lead.
If you are concerned about your health, please see your GP for advice.
Public Health South and the Dunedin City Council reported their findings into potential lead contamination of the Waikouaiti Water Supply at a public meeting on Wednesday 10 March. The meeting was held at the East Otago Events Centre, Waikouaiti at 7pm.
The meeting discussed the results of the blood tests that have taken place over the past few weeks. The Dunedin City Council also updated the community on its investigations into potential causes of the elevated lead levels detected in the water supply, and the next steps.
Public meeting, 5 February 2021
A public meeting was held on Friday 5 February to share information, including health impacts of lead, what we knew about the exposure at this time, and about the community blood testing to help us determine the next steps for managing this from a health perspective.
A video of the meeting can be found here.
Results from community blood testing
Over 1500 residents from participated in community blood tests, to help understand if they had experienced long term exposure to lead through the water supply.
The results from this testing found that people in the communities generally have blood lead levels below notifiable levels and in line with national data, and long-term exposure to lead from the water supply seems unlikely.
Public Health South is still advising residents to not drink the water while the investigation into the cause of the elevated lead readings is ongoing.
The main findings from the blood lead level tests were:
- No one had a blood lead level that caused acute harm
- Very few blood lead levels were above the new, lower threshold for notification (0.24 μmol/L)
- Blood lead levels in adults and young people aged 10-17 were in line with baseline study
- Blood lead levels in children aged 5-9 years were slightly higher than baseline study. The reason for this is not certain. While the water supply cannot be ruled out, information suggests other environmental reasons including seasonality may be more important.
- The national study did not include children under the age of 5, so no comparison is possible for that age group.
- There was no difference able to be detected for those who only drank the local water supply compared with those who did not, in either children or adults (but very small sample size, especially for children, and some missing data)
- There was no difference in blood lead levels based on where in the townships residents live
- There were two results for children and 36 for adults above the notifiable levels. Assessments found alternative explanations for these lead levels and health officials are providing advice to these individuals.
We expected most, if not all, people to have detectable levels of lead in their blood, as they will right across New Zealand.
Overall, blood lead levels have decreased dramatically in the past 40 years, to around 10 per cent of the levels detected in the 1970s.
However, New Zealand levels are higher than those reported in the United States, and we need to do what we can reduce exposure to lead.
Further information can be found in the presentation provided to the Waikouaiti, Karitane and Hawksbury Village residents here.
What is lead?
Lead has been a huge part of our industrial history. In the past, it has been used in paint, petrol and in range of household items. That said, it has no benefit to the human body and as we learn more about the impacts of lead, we are working towards removing it from our homes and our environments. If people are exposed to lead it can accumulate in the body over time. Prolonged exposure to a low level of contamination can lead to adverse health effects over time. People in countries such New Zealand are exposed to lead from many other sources around the home. Lead exposure is not a new problem - people have been exposed to lead for many decades. As a result of our efforts to remove lead from the environment, the amount of lead in our bodies has reduced dramatically over the generations.
Who is most vulnerable?
Infants, older people, children up to six years of age, pregnant women and their babies are the most susceptible to any adverse health effects from lead.
Is there usually lead in our water?
Lead can be present in drinking water dissolved from natural sources, or from household plumbing systems containing lead. The amount of lead dissolved will depend on the characteristics of the water and how long the water has been sitting in the pipes.
What do we know about the possible exposure so far?
The test results show that there have been some intermittent spikes of high levels in some locations, but with most results in between those spikes below the acceptable level. We do know that the water does not contain high levels of lead all the time, but it is not clear how often the spikes have happened. To ensure safety, we have advised not drinking the water until we can be assured the levels are acceptable for human health. There has only been one result so far that showed elevated levels at the reservoir. This result was in the ‘raw’ water. When treated, the result was below the maximum acceptable level. ESR has concluded that the risk to lead exposure through the Waikouaiti drinking water system is likely to be low based on a review of the available information. However, intermittent spikes of high lead levels in water is not a common situation and so previous experience and reports are few.
What actions are being taken to protect our health in the short term? What’s being done about this in the long term?
The most important action taken is that the community has been advised to stop drinking or using it for food preparation, and ensuring safe drinking water is available. By not drinking the tap water, you are no longer at risk of lead exposure from it. Boiling does not decrease lead content in water and may in fact concentrate it.
The tankered water will be available for as long as is needed. Health officials are working closely with the Council who are looking into the issue and will provide updates as soon as more information is known.
Free blood tests for lead levels will be available next week in the community. This will help us understand whether this has been an ongoing issue, and whether it has had an impact on people's health.
The results of these tests and other investigations into the water system will help us determine the next steps. We will share the results with you and hold another public meeting.
Why did we do blood tests, rather than other kinds of testing?
In NZ and in fact in the USA (Centres for Disease Control) recommends blood lead levels as the best way to determine lead exposure. While hair levels can be used there is no consistent standard way to measure and so results are not easily compared.
What are the side effects of elevated lead levels?
Symptoms in adults can include tiredness, mood changes, memory impairment, sleeplessness, irritability, headaches, joint pains and gastro-intestinal symptoms: lack of appetite, nausea, diarrhoea, constipation, stomach pains and weight loss. Young children may not exhibit any obvious illness but it may affect development if they have had exposure over time.
Can lead pass from a pregnant mother to her baby?
Yes, lead can pass through the placenta from pregnant women to their unborn baby, and this can be harmful for the developing baby. The level of lead that may cause harm is not yet well understood. If there are elevated levels in pregnant women, we would refer them to our specialist services for further assessment and monitoring.
Can I breastfeed my baby?
While it is possible for mothers to pass lead on to unborn babies and to infants through breastmilk, our advice is to continue breastfeeding due to all of the benefits breastfeeding gives.
What should I do if I have health concerns?
If you are unwell and have concerns about your health, please contact your usual GP, who will be able to provide you with the right health advice.
What does a high result mean?
If a high level is detected, your GP will be notified and public health will contact you. The most important action is to identify and stop any further exposure to lead – public health will help identify any other possible sources. If blood levels are very high, then there are treatments that can be used.
What other precautions can I take?
Precautions you can take include:
- Making sure children’s diets are high in iron, calcium and vitamin C as this decreases the amount of lead they absorb. It is especially important to ensure infant formula is not made from tap water until advised otherwise.
- being careful when scraping paint in old houses
- flushing your taps every morning – for about 30 seconds before use
- washing your hands
- washing dummies and toys frequently – especially if used outside
- avoiding drinking water collected from your roof if it has lead fittings such as lead-head nails.
I live in the area - how long will we have to use tankered water?
It is not yet clear how long we will ask residents to not drink tap water. This will depend on the results of the investigations into the cause of the elevated lead readings, and how easily they can be addressed.
I have not been available to get tested at the allotted dates times. How can I get my test?
You can go to your General Practitioner and arrange a test. Depending on the practice, this may be done at the practice, or a form will be given to you to take to the lab. Tests undertaken by Friday 19 February were free as part of this investigation.
I am currently out of town but I have lived in Waikouaiti, Merton/Hawksbury Village or Karitane in the recent past?
You will need to contact your GP to arrange a test. Testing will be funded for people who have lived or worked for at least one month in Waikouaiti, Karitane or Hawksbury over the past 12 months, and for pregnant women and formula fed babies who have spent at least two weeks in these towns over the past 12 months. The funding mechanism for this is being currently being worked on. If you are charged for a test, please keep your receipt. We also ask that you contact Public Health South so that we can send you a questionnaire – the same questionnaire people have been asked to fill out at the testing centres in Waikouaiti and Karitane. Please email email@example.com
How long were the tests free?
For eligible people, the tests were free until Friday 19 February.
I have a crib in Waikouaiti or Karitane and I am only there from time to time. Am I still at risk?
The risk to people who do not permanently live or work in Waikouaiti, Karitane or Hawksbury is low. However, as part of the investigation, testing was funded for people who lived or worked for at least one month in Waikouaiti, Karitane or Hawksbury over the past 12 months, and for pregnant women and formula fed babies who have spent at least two weeks in these towns over the past 12 months.
What can we do to prevent exposure to lead?
More information on the Ministry of Health's website
Advice from the Ministry of Primary Industries
Can I water vegetable garden, fruit trees, lawns and other plants?
A public meeting was held on Friday 5 February to share information, including health impacts of lead, what we know about the exposure so far, and about the community blood testing to help us determine the next steps for managing this from a health perspective.
Is it safe to eat local animal products and/or animals drinking water from the local water supply?
Based on the current information received from Council, the Ministry for Primary Industries advises there is minimal risk to food safety at this stage. There would need to be longer-term exposure at high lead levels in the water to make animal products such as dairy or eggs unsafe. Lead does not typically build up in muscle tissue (meat such as beef, pork, lamb or poultry) at the levels reported in the water.
Is it safe to eat food and vegetables grown locally and watered with the local water supply?
From the current information received from the Council, MPI advises there are minimal risks to commercially grown crops in the affected areas. The lead contamination would have to be sustained and chronically over the Maximum Acceptable Value in order to affect commercial growers. The risk to animal welfare is low given that most commercial farmers use their own water supply.
An information sheet with frequently-asked questions for those in affected communities can be found here:
More information can be found on the DCC website.