Relationship between ozone and temperature during the 2003 heat wave in France: consequences for health data analysis
1 Inserm, U618, Tours, F-37000 France; Univ François Rabelais, Tours, F-37000 France; IFR 135, Tours, F-37000, France
2 DRSM Centre, Orléans, F-45000, France
3 Lig'Air, Orléans, F-45000, France
BMC Public Health 2006, 6:261 doi:10.1186/1471-2458-6-261Published: 20 October 2006
PAPRICA is a research program designed to estimate the impact on the health of patients with chronic respiratory insufficiency of a prevention strategy based on notification of ozone pollution. The first year of this study was conducted during the 2003 heat wave, and high temperatures were therefore considered as a confounding factor in the data analysis. The aim of the present study was to assess the relationship between ozone and temperature in order to propose a methodology to distinguish between the effects of ozone and temperature on the impact of a prevention strategy with regard to ozone pollution.
Multivariate analyses were used to identify associated climate and ozone pollution profiles. This descriptive method is of great value to highlight the complexity of interactions between these parameters.
Ozone concentration and temperature were strongly correlated, but the health impact of ozone pollution alone will be evaluated by focusing on situations characterized by ozone concentrations above 110 μg/m3/8h (air quality guidelines to protect human health defined by the French legislation) and temperatures lower than 26°C, below the discomfort threshold.
The precise relationship between ambient ozone concentration and temperature identified during the PAPRICA 2003 study period will be used in analysing the PAPRICA health data.