Environmental Allergens: from Asthma to Hay Fever and Beyond

Abstract

Climate change has many impacts on environmental allergens and allergic diseases such as asthma and hay fever. Our knowledge of these impacts has grown considerably over the last 2 decades or so, and the last two and a half years in particular have seen a surge in research published on this topic. This report reviews the work published on climate change, allergens and allergic diseases since 1 January 2013. The review focusses on literature published in the peer-review journal literature, although a number of other prominent sources are also examined. Research of particular significance over the past two and a half years or so includes experimental studies that have quantified changes in allergenicity of pollen under combinations of elevated carbon dioxide and drought stress (for ragweed) and ozone (for Timothy grass). Other extensions of the research on this topic include a number of studies that are considering the impacts of climate change on allergic diseases with increasing sophistication and power. The review also considers recent research related to climate change adaptation in the context of impacts on allergens and allergic diseases. In conclusion, the latest research overall reaffirms this impact as one of the most important impacts of climate change on human health.

Climate Change and Future Pollen Allergy in Europe

“…To our knowledge, this is the first study to model the future impacts of climate change on plant distribution, plant life cycles, and pollen production and dispersal, as well as their subsequent impacts on pollen concentrations and allergy. Climate change consequences will not be restricted to ragweed, and a recent review has highlighted a range of other pollen-producing species that may be affected ( Beggs 2015 ). Our methods provide a framework for other studies investigating the impacts of climate change on pollen allergy for these other species.…”

“…Climate change is likely to affect allergic disease ( Smith et al 2014 ), and the view of clinical experts is that these diseases will increase under climate change ( Bielory et al 2012 ) in part because of the impact on allergenic plant species ( Shea et al 2008 ). Impacts on allergens may be one of the most important consequences of climate change for human health ( Beggs 2015 ). Climate change has already been suggested as one factor behind the increasing prevalence of allergic asthma ( Beggs and Bambrick 2005 ).…”

“…Pollens are a major cause of symptoms in people with allergic disease, but there is no quantitative assessment of how future climate change may affect the levels of pollen allergy in humans because the influence of climate change is complex ( Reid and Gamble 2009 ; Smith et al 2014 ). For example, an altered climate will affect the range of allergenic species as well as the timing and length of the pollen season, and elevated carbon dioxide (CO 2 ) may increase plant productivity and pollen production ( Beggs 2015 ). Climate change may also affect the release and atmospheric dispersion of pollen ( Bielory et al 2012 ).…”

Aeroallergens and Climate Change in Tulsa, Oklahoma: Long-Term Trends in the South Central United States

“…Many scientific papers have addressed the effects of climate change on plants known to produce allergenic pollen. Warmer temperatures in many areas of the northern hemisphere have led to earlier spring pollen seasons, increased pollen intensity, and longer pollen seasons along with more suffering among those with pollen allergies and asthma (4,(7)(8)(9)(10)(11)(12)(13). However, not all areas and not all plant species have been affected by climate change.…”

Invasive Mesquite (Prosopis juliflora), an Allergy and Health Challenge

“…Due to higher atmospheric temperatures, local conditions in many areas will also become dryer which would facilitate the production of more pollens (e.g., for Prosopis), especially in arid and semi-arid areas. This can cause further negative consequences for the local inhabitants [59,60]. The patterns of sensitization to pollens depend on exposure risks which vary depending on the environmental characteristics (climate, geography, vegetation, etc.)…”