Retorts

Airing the Issue

The contribution of Dr Gavin Fisher to the ongoing discussion of New Zealand's air quality was appreciated [Retorts, Dec/Jan]. Increased public awareness of the associated environmental issues and their controversial nature is very mportant.

Most significantly, I must briefly consider Dr Fisher's a priori conclusion that cost-effective toxicological and/or epidemiological air quality research cannot be done in this country. Physical and chemical monitoring currently done by researchers and regional councils is indeed an excellent means of determining the quantity of fine/respirable particle matter and the distribution and concentration of indicative compounds in air.

However, understanding if and/or how air pollutants harm the urban community requires consideration of the entire complex chemical mixture including possible emergent synergies in terms of biological activity/response, which is the reason for toxilogical and epidemiological research. I agree with Dr Fisher that the complexity involved cannot be underestimated but this is also why overseas data can only be indicative and local data are urgently needed.

Consequently, limited research funds in New Zealand have been directed at the collection of local data for the study of these issues. Local epidemiological research is not only established, but its publication in international, peer-reviewed scientific journals assures its validity and high quality (e.g., Harre et al. 1997, Thorax 52:1040-1044).

Dr Fisher is right that populations of New Zealand's cities are relatively small, but appropriate and valid statistical techniques exist for relating physical/chemical monitoring and health effects data as shown by a number of international studies (e.g., Burnett et al. 1994, Environ. Res., 72:24-31).

I agree with Dr Fisher that monitoring particle and chemical concentrations, international research and local legislation are needed to manage our air quality. However, focused, well-designed biological research is not only possible but essential in New Zealand for airshed managers to be able to make informed decisions including environmental health effects.

Janine Clemons, Environmental Toxicologist, Landcare