Components of particulate matter air-pollution and brain tumors

Background Air pollution is an established carcinogen. Evidence for an association with brain tumors is, however, inconclusive. We investigated if individual particulate matter constituents were associated with brain tumor risk. Methods From comprehensive national registers, we identified all (n = 12 928) brain tumor cases, diagnosed in Denmark in the period 1989–2014, and selected 22 961 controls, matched on age, sex and year of birth. We established address histories and estimated 10-year mean residential outdoor concentrations of particulate matter ˂ 2.5 µm, primarily emitted black carbon (BC) and organic carbon (OC), and combined carbon (OC/BC), as well as secondary inorganic and organic PM air pollutants from a detailed dispersion model. We used conditional logistic regression to calculate odds ratios (OR) per inter quartile range (IQR) exposure. We adjusted for income, marital and employment status as well as area-level socio-demographic characteristics. Results Total tumors of the brain were associated with OC/BC (OR: 1.053, 95%CI: 1.005–1.103, per IQR). The data suggested strongest associations for malignant tumors with ORs per IQR for OC/BC, BC and OC of 1.063 (95% CI: 1.007–1.123), 1.036 (95% CI: 1.006–1.067) and 1.030 (95%CI: 0.979–1.085), respectively. The results did not indicate adverse effects of other PM components. Conclusions This large, population based study showed associations between primary emitted carbonaceous particles and risk for malignant brain tumors. As the first of its kind, this study needs replication.</p

Intracranial tumors of the central nervous system and air pollution - A nationwide case-control study from Denmark

Background: Inconclusive evidence has suggested a possible link between air pollution and central nervous system (CNS) tumors. We investigated a range of air pollutants in relation to types of CNS tumors. Methods: We identified all (n = 21,057) intracranial tumors in brain, meninges and cranial nerves diagnosed in Denmark between 1989 and 2014 and matched controls on age, sex and year of birth. We established personal 10- year mean residential outdoor exposure to particulate matter < 2.5 μm (PM2.5), nitrous oxides (NOX), primary emitted black carbon (BC) and ozone. We used conditional logistic regression to calculate odds ratios (OR) linearly (per interquartile range (IQR)) and categorically. We accounted for personal income, employment, marital status, use of medication as well as socio-demographic conditions at area level. Results: Malignant tumors of the intracranial CNS was associated with BC (OR: 1.034, 95%CI: 1.005–1.065 per IQR. For NOx the OR per IQR was 1.026 (95%CI: 0.998–1.056). For malignant non-glioma tumors of the brain we found associations with PM2.5 (OR: 1.267, 95%CI: 1.053–1.524 per IQR), BC (OR: 1.049, 95%CI: 0.996–1.106) and NOx (OR: 1.051, 95% CI: 0.996–1.110). Conclusion: Our results suggest that air pollution is associated with malignant intracranial CNS tumors and malignant non-glioma of the brain. However, additional studies are needed

Ecology of the cardiovascular system: A focus on air-related environmental factors

Cardiology is a newcomer to environmental sciences. We aim to propose an original review of the scientific evidence regarding the effects of the environment on cardiovascular health. We report first influences of air-related environmental factors. Air temperature has a strong influence on cardiovascular mortality characterized by a V-like relationship confirming that both cold and hot periods have negative cardiovascular impacts. Furthermore, dynamic changes in temperature are likely more important than the absolute air temperature level. Cardiovascular reactions to air temperature are predominantly driven by increase in sympathetic tone. Indoor pollutants are mainly represented by smoke from cooking stoves and environmental tobacco smoke (ETS), and both are associated with increased cardiovascular mortality and morbidity. ETS is characterized by a curvilinear dose–effect relationship, showing already a significant effect even at low level of exposure and no threshold in effect appearance. Underlying ETS pathophysiology involves both effects of nicotinic stimulus on the sympathetic system and vascular oxidative stress. Smoking bans, as mitigation measures, were associated with a decrease in cardiovascular events. Long-term exposure to particulate air pollution was more recently recognized as an independent risk factor of cardiovascular mortality. Short-term increases in air pollution were also associated with an increased risk of myocardial infarction, stroke, and acute heart failure. Numerous experimental studies demonstrated that air pollution promotes a systemic vascular oxidative stress reaction followed by endothelial dysfunction, monocyte activation, and some proatherogenic changes of lipoproteins. Furthermore, air pollution favors thrombus formation as a result of increase in coagulation factors and platelet activation. Further studies are required to confirm that stricter air quality regulation or antioxidant regimen translate into some clinical benefits. In conclusion, ambient air temperature and pollution are major contributors to cardiovascular diseases. Improving air quality is now part of cardiovascular prevention.SCOPUS: re.jinfo:eu-repo/semantics/publishe

The impact of outdoor air pollution on COVID-19: a review of evidence from in vitro, animal, and human studies

International audienceStudies have pointed out that air pollution may be a contributing factor to the coronavirus disease 2019 (COVID-19) pandemic. However, the specific links between air pollution and severe acute respiratory syndrome-coronavirus-2 infection remain unclear. Here we provide evidence from in vitro, animal and human studies from the existing literature. Epidemiological investigations have related various air pollutants to COVID-19 morbidity and mortality at the population level, however, those studies suffer from several limitations. Air pollution may be linked to an increase in COVID-19 severity and lethality through its impact on chronic diseases, such as cardiopulmonary diseases and diabetes. Experimental studies have shown that exposure to air pollution leads to a decreased immune response, thus facilitating viral penetration and replication. Viruses may persist in air through complex interactions with particles and gases depending on: 1) chemical composition; 2) electric charges of particles; and 3) meteorological conditions such as relative humidity, ultraviolet (UV) radiation and temperature. In addition, by reducing UV radiation, air pollutants may promote viral persistence in air and reduce vitamin D synthesis. Further epidemiological studies are needed to better estimate the impact of air pollution on COVID-19. In vitro and in vivo studies are also strongly needed, in particular to more precisely explore the particle–virus interaction in air