The role of outdoor air pollution and climatic changes on the rising trends in respiratory allergy (original) (raw)

Interaction Between Air Pollutants and Pollen Grains: The Role on the Rising Trend in Allergy

Reports of biochemistry & molecular biology, 2018

Asthma and allergic diseases cases have risen in recent decades. Plant pollen is considered as the main aeroallergen causing allergic reactions. According to available data, urban residents experience more respiratory allergies than rural residents mainly due to the interaction between chemical air pollutants and pollen grains. This interaction can occur through several mechanisms; chemical pollutants might facilitate pollen allergen release, act as adjuvants to stimulate IgE-mediated responses, modify allergenic potential, and enhance the expression of some allergens in pollen grains. This review focuses on the most recent theories explaining how air pollutants can interact with pollen grains and allergens.

Environmental contributions to allergic disease

Current allergy and asthma reports, 2001

The environment is a major contributor to allergic disease, and great effort is being expended to identify the chemical pollutants and allergens that make a significant impact. Exposure to high levels of ozone, sulfur dioxide, nitrogen dioxide, and diesel exhaust particles is known to reduce lung function. Studies continue to delineate the role of these particles as adjuvants and carriers of allergens into the respiratory system. Current studies also show the exacerbation of allergic disease through fungal spore inhalation and continue to document the role of pollen in allergic rhinitis. Pollen also was recently associated with asthma epidemics, especially after thunderstorms. Forecasting models currently are being developed that predict the trajectories of pollen dispersal and may allow increased avoidance of dangerous outdoor conditions.

Air pollution and allergens

J Investig Allergol Clin …, 2007

It is well known that the prevalence of allergic diseases has increased in recent decades in the industrialized world. Exposure to environmental pollutants may partially account for this increased prevalence. In effect, air pollution is a growing public health problem. In Europe, the main source of air pollution due to particles in suspension is represented by motor vehicles-particularly those that use diesel fuel. Diesel exhaust particles (DEPs) are composed of a carbon core upon which high-molecular weight organic chemical components and heavy metals deposit. Over 80% of all DEPs are in the ultrafi ne particle range (< 0.1 µm in diameter). Air pollutants not only have a direct or indirect effect upon the individual, but also exert important actions upon aeroallergens. Pollen in heavily polluted zones can express a larger amount of proteins described as being allergenic. Through physical contact with the pollen particles, DEPs can disrupt the former, leading to the release of paucimicronic particles and transporting them by air-thus facilitating their penetration of the human airways. Climate change in part gives rise to variations in the temperature pattern characterizing the different seasons of the year. Thus, plants may vary their pollination calendar, advancing and prolonging their pollination period. In addition, in the presence of high CO2 concentrations and temperatures, plants increase their pollen output. Climate change may also lead to the extinction of species, and to the consolidation of non-native species-with the subsequent risk of allergic sensitization among the exposed human population. In conclusion, there is suffi cient scientifi c evidence on the effect of air pollution upon allergens, increasing exposure to the latter, their concentration and/or biological allergenic activity.

Allergic diseases and air pollution

2013

The prevalence of allergic diseases has been increasing rapidly, especially in developing countries. Various adverse health outcomes such as allergic disease can be attributed to rapidly increasing air pollution levels. Rapid urbanization and increased energy consumption worldwide have exposed the human body to not only increased quantities of ambient air pollution, but also a greater variety of pollutants. Many studies clearly demonstrate that air pollutants potently trigger asthma exacerbation. Evidence that transportation-related pollutants contribute to the development of allergies is also emerging. Moreover, exposure to particulate matter, ozone, and nitrogen dioxide contributes to the increased susceptibility to respiratory infections. This article focuses on the current understanding of the detrimental effects of air pollutants on allergic disease including exacerbation to the development of asthma, allergic rhinitis, and eczema as well as epigenetic regulation.

Allergy and asthma: Effects of the exposure to particulate matter and biological allergens

Respiratory Medicine, 2015

The prevalence of asthma and allergies including atopy has increased during the past decades, particularly in westernized countries. The rapid rise in the prevalence of such diseases cannot be explained by genetic factors alone. Rapid urbanization and industrialization throughout the world have increased air pollution and population exposures, so that most epidemiologic studies are focusing on possible links between air pollution and respiratory diseases. Furthermore, a growing body of evidence shows that chemical air pollution may interact with airborne allergens enhancing the risk of atopic sensitization and exacerbation of symptoms in sensitized subjects. These phenomena are supported by current in vitro and animal studies showing that the combined exposure to air pollutants and allergens may have a synergistic or additive effect on asthma and allergies, although there is an insufficient evidence about this link at the population level. Further research is needed in order to elucidate the mechanisms by which pollutants and biological allergens induce damage in exposed subjects. The abatement of the main risk factors for asthma and allergic diseases may achieve huge health benefits. Thus, it is important to raise awareness of respiratory allergies as serious chronic diseases which place a heavy burden on patients and on society as a whole.

Impacts of air pollution exposure on the allergenic properties of Arizona cypress pollens

2009

Epidemiological studies have demonstrated that urbanization and high levels of vehicle emissions correlated with the increasing trend of pollen-induced respiratory allergies. Numerous works have investigated the role of pollutants in the pathogenesis of respiratory diseases but impacts of anthropogenic pollution on pollen allergenic properties are still poorly understood. The objective of this survey was to evaluate impacts of the traffic-related pollution on the structure and allergenic protein content of Arizona cypress (Cupressus arizonica, CA) pollens, recognized as a rising cause of seasonal allergy in various regions worldwide. According to our results, traffic-related air pollution by its direct effects on the elemental composition of pollens considerably increased the fragility of the pollen exine, causing numerous cracks in its surface and facilitating pollen content liberation. Pollen grains were also covered by numerous submicronic orbicules which may act as effective vectors for pollenreleased components into the lower regions of respiratory organs. On the other hand, this study provides us reliable explications about the low efficiency of standard commercial allergens in the diagnosis of the Arizona cypress pollen allergy in Tehran. Although traffic related pollution affects the allergenic components of CA pollens, the repercussions on the respiratory health of urban populations have yet to be clarified and need further investigations.

How Exposure to Environmental Tobacco Smoke, Outdoor Air Pollutants, and Increased Pollen Burdens Influences the Incidence of Asthma

Environmental Health Perspectives, 2006

Asthma is a multifactorial airway disease that arises from a relatively common genetic background interphased with exposures to allergens and airborne irritants. The rapid rise in asthma over the past three decades in Western societies has been attributed to numerous diverse factors, including increased awareness of the disease, altered lifestyle and activity patterns, and ill-defined changes in environmental exposures. It is well accepted that persons with asthma are more sensitive than persons without asthma to air pollutants such as cigarette smoke, traffic emissions, and photochemical smog components. It has also been demonstrated that exposure to a mix of allergens and irritants can at times promote the development phase (induction) of the disease. Experimental evidence suggests that complex organic molecules from diesel exhaust may act as allergic adjuvants through the production of oxidative stress in airway cells. It also seems that climate change is increasing the abundance of aeroallergens such as pollen, which may result in greater incidence or severity of allergic diseases. In this review we illustrate how environmental tobacco smoke, outdoor air pollution, and climate change may act as environmental risk factors for the development of asthma and provide mechanistic explanations for how some of these effects can occur.

A Review of the Effects of Major Atmospheric Pollutants on Pollen Grains, Pollen Content, and Allergenicity

The Scientific World Journal, 2015

This review summarizes the available data related to the effects of air pollution on pollen grains from different plant species. Several studies carried out either onin situharvested pollen or on pollen exposed in different places more or less polluted are presented and discussed. The different experimental procedures used to monitor the impact of pollution on pollen grains and on various produced external or internal subparticles are listed. Physicochemical and biological effects of artificial pollution (gaseous and particulate) on pollen from different plants, in different laboratory conditions, are considered. The effects of polluted pollen grains, subparticles, and derived aeroallergens in animal models, inin vitrocell culture, on healthy human and allergic patients are described. Combined effects of atmospheric pollutants and pollen grains-derived biological material on allergic population are specifically discussed. Within the notion of “polluen,” some methodological biases ar...

Combined effects of air pollution and allergens in the city of Rome

Urban Forestry & Urban Greening, 2018

Urban green is an important aspect in the quality of life of citizens of modern cities. Nevertheless some ornamental plants cause allergic diseases in sensitive subjects that may be worsened by air pollution. Studies on air quality are usually addressed to the evaluation of single substances and their specific effects: little is known about the cumulative effect that different pollutants may have on human health. Even less is known about possible combined action of traditional air pollutants with pollen and spores that have huge effects, in terms of allergies and asthma, on citizenship of the urban areas. In this work the synergistic effect of PM 10 , PM 2.5 , NO 2 , O 3 and airborne pollens (belonging to 4 taxa: Cupressaceae/Taxaceae, Graminaceae, Olea and Urticaceae) was studied in the city of Rome during six years (from 2010 to 2015). For air pollutants, concentration values recorded by air-quality monitoring network of Rome were used. Pollens and spores data were detected by the Aerobiological Monitoring Centre of the University of Rome Tor Vergata. Effects on human health were evaluated on a group of 100 patients (aged between 4 and 18) by the Allergymonitor™ ã application that records daily symptoms of hay fever, bronchial asthma and the prescribed therapies. Data collected in the medical record were processed by 2 different Symptom Medication daily Scores and compared with time series of air concentration of mentioned pollutants, pollen and spores. Statistical analysis allowed highlighting when concomitant high levels of allergenic species and air pollution occur, the influence of meteorological parameters, of the flowering calendar, of taking drugs and how these aspects affect symptoms in patients.