Plant species have different degrees of allergenicity. A new index categorizing plants according their potential allergenicity (CARE-S) was developed by the National Public Health Center in Hungary. The categorization of plants by their allergenicity serves different purposes: informing allergic patients, warning consumers in horticultural stands, or evaluating and developing urban green areas. The regulation of allergenic plants in trade and their use in urban greening is a new, emerging application of allergenic categorization. The new system is based on genetically determined factors of plants: immunogenicity, morphology, and pollen production.
Based on the new method, 529 plant taxa were categorized, mostly trees common in urban areas in the Pannonian Biogeographical Region and 106 herbaceous/ornamental plants. Based on the allergenicity of each plant species and taxa, the allergen potential of urban green areas can be calculated. The new categorization system can be adopted for other biogeographic areas and for new plant varieties which are not included in the existing list. Additional benefits of the index are:
- providing a decision-making tool to prevent the introduction and dispersal/invasion of new allergenic plants,
- promoting the development of low-allergenic plant cultivars,
- identifying overlooked allergens, recommending their use in clinical tests,
- calling attention to plant taxa which need more research in allergology or botany.
As the index is evidence-based and reproducible, it can be used in legislation in order to reduce allergen pollen emissions of green areas.
Further information is available here.