Multiple studies have already shown the impact of the environment, including air pollutants, on cardiovascular and respiratory health. Whether these environmental indicators affect mental health is nonetheless still under debate. Furthermore, as people do not stay at the same place the whole day, it is difficult to assess their actual exposure. Using internal biomarkers of exposure (measurable biological indicator of exposure condition) and early health effect will enable Sciensano to gain more insight in these subjects.
Quantifying human exposure to the outdoor environment is a challenging task. Ambient concentrations of air pollutants at potentially harmful levels are ubiquitous in urban areas and subject to high spatial and temporal variability. At the same time, every individual has unique activity patterns. Epidemiological studies based on spatial temporal interpolation models or personal monitoring are extremely valuable. Nevertheless, their scientific contribution can be enhanced and integrated thanks to biomarkers. The latter have been introduced under the assumption that they could improve scientific research on health effects of air pollution and other exposures by:
- improving the personal exposure assessment because of the close biological link with the individual;
- increasing the understanding of action mechanisms, e.g. by measuring intermediate biomarkers;
- allowing the investigation of individual susceptibility.
Surrounding greenness is closely linked with air pollution is. Vegetation is known to reduce exposure to air pollution by taking up gaseous air pollutants and intercepting harmful particles. Residential greenness has more positive effects than the reduction in air pollution only. It has been associated with a lower adiposity weight, a higher birthweight, a higher attention rate in children and a higher self-perceived health.
In Belgium, ambient air pollution is still an intermittent problem as to meeting the European Union limit values. Moreover, as Belgium is densely populated, the population attributable fractions may be large. HuBiHIS aims to investigate in a human biomonitoring study (participants ≥ 18 years) whether the outdoor environment (air pollution and surrounding greenness) contributes to cardiovascular, respiratory and mental health in Belgium by integrating biomarkers of exposure and early health effects.
The overall objective of the HuBiHIS project is to complement the Health Interview Survey (HIS 2018) and the Belgian Health Examination Survey (BELHES) with biological samples to assess individual measures of environmental exposure and early health effects.
Specific objectives of the study
- To evaluate short- and long-term exposure to air pollution and surrounding greenness at a residency level, as well as (passive) smoking in association with respiratory, cardiovascular and mental health status in an adult/elderly population;
- To examine biomarkers of exposure (urinary black carbon load, polycyclic aromatic hydrocarbons and (hydroxy)cotinine) and biomarkers of early health effect (mitochondrial DNA content and telomere length) in an adult/elderly population in association with the environmental exposures (air pollution and surrounding greenness at residency level) and (passive) smoking;
- To evaluate the association between the previously described biomarkers of exposure and early health effect on the respiratory, cardiovascular and mental health statuses;
- To evaluate which lifestyle factors (BMI, socio-economic status, age, sex, smoking, etc.) are important determinants in the associations between the environmental exposures, the biomarkers of exposure and effect, and the health statuses.
Added value at the scientific level
The use of biomarkers will improve personal exposure assessment, as they strengthen the link with the individual. Furthermore, they improve the understanding of the underlying mechanisms ruling the environmental exposure and health effects.
Added value for public health
Biological samples and individual measures of environmental exposure will offer an added value in several domains of public health, as they offer an objective assessment base for monitoring. The HuBiHIS project will include for the first time a feasibility study to assess the health effects of air pollution exposure in Belgium using biomarkers of exposure and effect.