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.