Otago lead contamination: Blood tests begin for Waikouaiti residents

Waikouaiti, Karitane and Hawksbury residents have been urged not to drink tap water for a week. Photo / Peter McIntosh, ODT

A steady stream of Waikouaiti locals were waiting patiently at the East Otago Events Centre this afternoon, as blood testing of the community for lead began.

Twelve testing stations had been set up to assess whether a scare involving potential lead contamination of the town's water supply had affected anyone's health.

Residents of the Waikouaiti, Karitane and Hawksbury communities are being tested.

Lead being present in the blood is not in itself of concern to the SDHB.

Southern District Health Board medical officer of health Dr Susan Jack said if any blood lead levels were above the internationally accepted notifiable level of 0.24 umol/L then public health unit staff would undertake a more detailed risk assessment and provide advice to the person or family.

"We would seek to understand and provide information about removing the lead exposure source, and may follow up with a repeat blood test after 6 months. If there are higher levels in children, they would be referred to a paediatrician for assessment and management. Very high levels for children or adults would need an emergency assessment and management at hospital."

Test results will be returned over the next week or so.

"It is important to be aware that we expect most, if not all, people to have detectable levels of the lead in their blood," Dr Jack said.

"Further, we expect a number of people may have elevated blood lead levels as a result of other exposure, for example working with lead-based paint or other activities. Again, we cannot draw conclusions about the exposure to lead from the Waikouaiti water supply based on individual elevated results".

The SDHB will be reporting the results back to each individual or their parent and will not be communicating publicly on individual cases, she said.

"The combined results will then be analysed. This analysis will consider overall levels in comparison with the result of the population based on other studies, and taking into consideration other possible reasons for elevated results including people's age, occupations and hobbies."

This will help them understand whether or not the results suggest there has been any ongoing exposure to lead from the water supply in the affected communities, she said.

"This might also suggest if there are higher-risk areas of the water reticulation system."

These combined results will be shared with the community at a public meeting, and with the media. The process was expected to take two to three weeks.

DCC investigates possible source of lead

The Dunedin City Council said in a release today the latest interim water test results, from samples taken on February 4 and 5, showed low or non-detectable levels of lead in the water supply.

DCC is also continuing to investigate potential sources of contamination.

The work so far has confirmed the presence of lead joins in very old cast iron pipes in the Waikouaiti network.

While the joins have not been confirmed as the source of the intermittent significant spikes, work to replace the pipes has begun.

"We expect to replace about 4km of pipes as a result over the next few months and replace the old sections with temporary above-ground water pipes."

As well as increased daily water tests, the DCC has also launched a separate full catchment survey, testing for a range of contaminants across the wider catchment.

The DCC will also help residents who need help draining and refill their private water storage tanks, once the supply is re-established and the 'don't drink' notice is lifted.

Testing begins

Ammon Hunter was one of the first tested this afternoon.

"We feel fine, but you want to be sure," he said.

A stand was at the exit for people to get free supplies of fruit and vegetables, after concerns homegrown produce might also be tainted.

Dr Jack said more than 50 people had had blood tests in the first hour of the clinic opening.

"We have had a great response from the community. Today and tomorrow we have asked for people with young children in particular to come because we have people here who are skilled at taking bloods from young people."

The turn around time for lab tests was 2-3 days.

The pop-up clinic was not having any affect on the Covid-19 test programme, Dr Jack said.