Despite a continuous extension of life expectancy and a global improvement in health status of populations in most industrialized countries, individuals remain unequal in death and disease. Inequalities remain between population groups, and especially between social classes: As a general rule, socioeconomically disadvantaged populations are more strongly affected by various health problems compared to the most privileged ones. Reducing social health inequalities has become an explicit goal and debate of health policies over the past few years.
In spite of the numerous risk factors already identified, some of these inequalities remain unexplained. In light of this, it is suspected that environmental
nuisances, air pollution in particular, also contribute to social inequalities in health. The contribution of environmental exposure has been mentioned in the literature to explain part of the observed health inequalities, leading to hypotheses about disproportionate impacts of environmental risks according to the social characteristics of the population. Environmental exposures may contribute to health inequalities through (1) differential susceptibility, the deprived population could be more susceptible to air pollution effect due to a fragile health status, and/or (2) differential exposure, deprived populations could be exposed to a greater number of environmental nuisances and/or to a higher level of nuisances.
Air pollution in Europe – continuing public health problem
In 1997, the French Institute for Public Health Surveillance (InVS) set up the Air and Health Surveillance Program and coordinated or contributed to several European projects which were developed since then. The present article summarizes the main outcomes achieved by these projects over the last 15 years and explores future challenges to implement public health prevention measures.
Since the 1990s, several epidemiological studies have outlined the health effects of air pollution observed even at current levels. Health impact assessment methods contributed to quantify the impact of air pollution on mortality and morbidity, and the benefits resulting from the improvement of air quality for the population. All these studies illustrated the health and economic burden of the negative effects of air pollution. They also contributed to a change in perceptions regarding the impacts of air pollution. Improving population’s health can only be achieved through a sustainable improvement in air quality.
The influence of size, source and chemical composition on the health effects of particulate matter
Particular matter (PM) is a complex, heterogeneous mixture which changes in time and space. It encompasses numerous chemical components and physical characteristics, many of which have been cited as potential contributors to toxicity. As a consequence, identifying and quantifying the influences of specific components or source-related mixtures on measures of health-related impacts, especially when particles interact with other co-pollutants, represents one of the most challenging areas of environmental health research.
Current knowledge does not allow precise quantification or definitive ranking and indeed, associations may be the result of multiple components acting on different physiological mechanisms. Some results do suggest a degree of differential toxicity, namely more consistent associations with traffic-related PM air pollution, fine and ultrafine particles, particular metals and elemental carbon and a range of serious health effects, including increased morbidity and mortality from cardiovascular and respiratory conditions.
A carefully targeted programme of contemporary toxicological and epidemiological research, incorporating more refined approaches (eg. greater speciation data, more refined modelling techniques, accurate exposure assessment and better definition of individual susceptibility) and optimal collaboration amongst multidisciplinary teams is now needed. This will facilitate targeted management policies, more effective pollution control measures, and ultimately the goal of reducing disease attributable to ambient PM pollution.
Référence : “La pollution atmosphérique en Europe : un problème de santé publique persistant ” – Bulletin de l’Institut de Veille Sanitaire (InVs)