Key points

Air Pollution Episode

Last week was marked by an episode of fine particulate matter (PM10) pollution in several French urban areas.

In Auvergne, according to data released by Atmo Auvergne, the episode lasted between 1 and 5 days depending on the department, from March 11 to 16. The maximum value (over 24 hours) was recorded in the Riom/Clermont-Ferrand/Issoire area: 80 μg/m³ at the Chamalières station. On Monday, March 17, 2014, weather conditions were favorable for the dispersion of pollutants, allowing conditions to return to normal.

From a public health perspective, analysis of regional syndromic surveillance data (overall activity, asthma, malaise, dyspnea/acute respiratory failure, chronic bronchitis, heart failure, myocardial ischemia, headaches) across different age groups did not reveal any notable increase during this period.

However, several studies have shown that there does not appear to be a protective threshold below which no health impact is observed. The health effects of air pollution are observed even at the lowest concentrations, even in the absence of pollution “peaks.” Thus, the health impact of air pollution is primarily due to background levels of air pollution. Several cohort studies have shown that the long-term impact of chronic exposure to air pollution is significantly greater in terms of mortality or life expectancy than the short-term impacts observed.