5. Question No. 5—HealthHon EUGENIE SAGE (Green) to the Associate Minister of HealthQuestion No. 5—Health5. Hon EUGENIE SAGE (Green) to the Associate Minister of Health: Has she seen the recently published research that estimates up to 100 colorectal cancer cases per year may be attributable to nitrates in drinking water; if so what is her response?Hon Dr AYESHA VERRALL (Associate Minister of Health): I assume the member refers to the paper Nitrate contamination in drinking water and colorectal cancer: Exposure assessment and estimated health burden in New Zealand by Richards et al. in the journal of Environmental Research. That study relied on previous epidemiological studies suggesting an association between nitrates and colorectal cancer and assumed these associations were true to project the number of cancers that could occur in the New Zealand population. It did not directly assess the relationship between individual exposure to nitrate and colorectal cancer in New Zealand. The authors and their paper and their press release acknowledge this is one of the limitations of their study. I am aware of emerging research in this field and have instructed health officials to monitor new evidence as it comes to light and to report back to me as appropriate.Hon Eugenie Sage: When she said in answer to written question No. 4695 that the Ministry of Health will respond appropriately to identified risks to public health." what action is the ministry taking in response to the growing number of studies about the potential health impacts of nitrate levels in drinking water?Hon Dr AYESHA VERRALL: The Ministry of Health has reviewed the association between nitrates and colorectal cancer this year and in addition in response to other questions about a hypothesised relationship between nitrates and perinatal outcomes has commissioned a systematic review of the evidence by the Liggins Institute of Auckland University into that association. That report I believe will be published soon.Hon Eugenie Sage: What reports if any has she had from the now-disbanded informal working group established in late 2019 to consider possible links between nitrates and bowel cancer in New Zealand?Hon Dr AYESHA VERRALL: The process that I outlined in my previous answer is the process that we have used to evaluate the scientific evidence of any association between nitrates and drinking water. Other work may be required if other associations come to light but for the time being I am happy with the process that the ministry has been through.Hon Eugenie Sage: Does the Minister agree with Dr Chambers' statement: "the results support the need to take a precautionary approach towards nitrate contamination in New Zealand"; if she does agree with Dr Chambers' statement what does she consider a "precautionary approach" to chronic exposure to nitrate in drinking water sources requires?Hon Dr AYESHA VERRALL: This Government takes the importance of safe drinking water extremely seriously and that is the basis of our three waters reforms which include alterations to the regulations of drinking water in response to the events of drinking-water contamination at Havelock North. With respect to the question about the precautionary principle we will act on evidence and as I have mentioned the evidence in this issue is unclear. I've had the experience in this role of having to stop a town from drinking its drinking-water supply and it is incredibly disruptive. So I am happy with an approach where we act on conclusive evidence.Hon Eugenie Sage: So how much more evidence of risks to human health from nitrate contamination in drinking water is needed before the Government takes action to protect the public and drinking-water supplies from nitrate pollution?Hon Dr AYESHA VERRALL: The evaluation of an environmental exposure with a public health outcome is incredibly complex and usually requires evaluating multiple different features of the evidence. I continue to ask the Ministry of Health to review that. I do note that two other university epidemiologists in relation to this issue have also tried to contextualise the scale of the risk here. For example Professor Brian Cox said "At this stage there is no cause for alarm. Even those drinking nitrate-rich water the risk is small compared to eating a high diet in processed meat." Professor Michael Baker said "We need to have a reasonable sense of proportion. The evidence is on the weaker end of the spectrum and the association does not necessarily mean causation."Hon Eugenie Sage: Supplementary [Interruption]SPEAKER: Order!Hon Eugenie Sage: Does the Minister consider that nitrogen pollution in rivers and aquifers from intensive dairying in Aotearoa New Zealand is a risk to human health?Hon Dr AYESHA VERRALL: I believe that nitrate pollution of fresh water is an environmental problem that I am concerned about. I support this Government's action to clean up fresh water for the reason that it is an environmental problem.SPEAKER: Now I haven't done this for a long time but after I called order then three National Party members interjected while Eugenie Sage was on her feet. I just want to indicate to members that that is not acceptable and the consequences of it—and it might have been two National and one ACT just to be absolutely fair. There were at least—I'm getting negatives from the front and positives from the back so some people need to get the story constant. Is there a further supplementary?"