Exposure to ultrafine particles in children until 18 years of age: A systematic review

Abstract

Airborne ultrafine particles (UFP) have been related to adverse health effects, but exposure in vulnerable population groups such as children is still not well understood. We aim to review the scientific literature regarding personal exposure to UFP in different microenvironments in populations until 18 years of age. The bibliographical search was carried out in July 2019 using the online database PubMed and was completed with references in articles found in the search. We selected the studies that used continuous counters and measured UFP levels in both specific microenvironment (houses, schools, transport, etc) and personal exposure. Finally, 32 studies fulfilled the criteria: of these, 10 analyzed personal exposure and 22 examined UFP levels in the microenvironment (especially in schools or nurseries (18/22)) and five in various microenvironments (including dwellings and means of transport, where exposure levels were higher). The characteristics of the microenvironments with the greatest levels of UFP were being close to heavy traffic or near cooking and cleaning activities. This review revealed the wide differences in exposure assessment methodologies that could lead to a lack of uniform and comparable information about the real UFP exposure in children.

Indoor exposure levels of bacteria and fungi in residences, schools, and offices in China: A systematic review

“…13 studies focused on office buildings, 34,42‐44,46,67,69,71,72,74‐76,80 26 studies were related to schools, 25,27,29,35,38‐41,43,47‐49,51,52,54,56,58,60,61,64‐66,68,72,73,77 and 20 studies investigated residences 28,30‐33,36,37,45,50,53,55,57,59,62,63,70,72,77‐79 . Schools were the most studied microenvironments, probably because the intensive density of students is more likely to cause microorganisms, and health policies often target at schools 81 . More than half of these researches on schools were done on university campuses.…”

“…28,[30][31][32][33]36,37,45,50,53,55,57,59,62,63,70,72,[77][78][79] Schools were the most studied microenvironments, probably because the intensive density of students is more likely to cause microorganisms, and health policies often target at schools. 81 More than half of these researches on schools were done on university campuses. Compared to fungi, researchers were more concerned with bacterial concentrations, with 48 studies reported bacterial concentration levels, 25,[27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][43][44][45][46][47][48][49][50][51][53][54]…”

Meta-analysis on short-term exposure to ambient ultrafine particles and respiratory morbidity

“…https://doi.org/10.1183/16000617.0116-2020 measurement sites to allow more powerful studies. Previous reviews have also reported the difficulty in combining information from multiple studies due to the wide differences in exposure assessment methods [29]. The comparison of results from different studies is even harder considering their use of various exposure periods, age groups and respiratory morbidity indexes.…”

Particle number emission rates of aerosol sources in 40 German households and their contributions to ultrafine and fine particle exposure

“…Moreover, residential indoor air quality is seldom subject to official regulations. For a better understanding of indoor air quality, further studies on indoor particle exposure, in particular ultrafine particles, are needed 11–14 …”

“…For a better understanding of indoor air quality, further studies on indoor particle exposure, in particular ultrafine particles, are needed. [11][12][13][14] Aerosol particles in indoor air are usually a mixture of particles originating from indoor and outdoor various sources, where particle size distribution and chemical composition change over time. This change is dominated by several processes and factors such as the emission profile of indoor sources, the building shell penetration factor, the ventilation rate, and particle losses due to deposition on surfaces and coagulation.…”