Dear Taumata Arowai Team,

I am writing to inquire about the recent increase in the Maximum Acceptable Value (MAV) for azinphos-methyl in drinking water from 0.004 mg/L to 0.1 mg/L, which represents a 2400% rise.

This increase is perplexing, particularly given that azinphos-methyl was effectively banned over a decade ago following the New Zealand Environmental Risk Management Authority's decision to phase out its use. Given the ban, I would appreciate clarification on why an increase in the allowable concentration in drinking water is deemed necessary, especially considering its potential environmental and health impacts.

Thank you for your time and consideration, and I look forward to your response.

Mr Davies

Dear Taumata Arowai–the Water Services Regulator,

Thank you for your response and for providing the background information regarding the increased Maximum Acceptable Value (MAV) for azinphos-methyl. I have some additional questions regarding this increase, especially in light of comparisons with international standards.

1. Toxicological Basis for MAV Increase

Could you please provide details on the toxicological data or studies used to determine the new MAV of 0.1 mg/L? Given this substantial increase, are there findings that support the safety of this level for long-term human consumption?

2. International Comparisons

I’ve noted that New Zealand’s MAV of 0.1 mg/L is significantly higher than those of other countries, such as Canada (0.02 mg/L) and Australia (0.03 mg/L). Specifically, New Zealand’s allowable level is 5 times higher than Canada’s and 3.3 times higher than Australia’s. This equates to New Zealand’s level being 400% higher than Canada’s and 233% higher than Australia’s. Could you explain why such a high MAV was chosen, especially given the international context?

3. Reasons for Moving Away from Precautionary Limits

Could you provide clarification on why the provisional MAV of 0.004 mg/L was raised by such a large margin, particularly for a substance banned due to health concerns? Was the previous limit deemed overly restrictive based on new evidence?

4. Public Health Risk Assessment

Has a recent assessment been conducted on the health impacts of this increased MAV? If available, a summary of findings regarding the long-term safety implications of this concentration would be helpful.

I appreciate your assistance in addressing these questions. Given the significant difference between New Zealand’s MAV and those of other countries, understanding the basis for this increase is crucial for public confidence.

Yours faithfully,

Mr Davies