Centre for Environmental and Occupational Health Research, School of Public Health and Family Medicine, University of Cape Town, Cape Town, South Africa.
Swiss Tropical and Public Health Institute, Socinstrasse 57, P.O. Box, 4002, Basel, Switzerland; University of Basel, Petersplatz 1, 4003, Basel, Switzerland.
Environ Pollut. 2020 May;260:114023. doi: 10.1016/j.envpol.2020.114023. Epub 2020 Jan 27.
The individual effects of biological constituents of particulate matter (PM) such as fungal spores, on lung function in children are not well known. This study investigated the seasonal short-term effect of daily variation in Alternaria and Cladosporium fungal spores on lung function in schoolchildren.
This panel study evaluated 313 schoolchildren in informal settlements of the Western Cape of South Africa, exposed to spores of two commonly encountered fungi, Alternaria and Cladosporium species. The children provided forced-expiratory volume in 1-s (FEV) and peak-expiratory flow (PEF) measurements thrice daily for two consecutive school-weeks in summer and winter. Daily PM levels, from a stationary ambient air quality monitor and fungal spore levels using spore traps were measured in each study area throughout the year. The effects of Alternaria and Cladosporium spores, on lung function were analysed for lag periods up to five-days, adjusting-for PM, other pollen exposures, study area, and other host and meteorological factors. Same-day exposure-response curves were computed for both fungal species.
There was more variability in Alternaria spores level with noticeable peaks in summer. There were consistent lag-effects for Alternaria on PEF compared to Cladosporium, with the largest PEF deficit observed in winter (mean deficit: 13.78 L/min, 95%CI: 24.34 to -3.23 L/min) per 10spores/m increase in Alternaria spores on lag day-2. Although there were no observable lag-effects for Alternaria and Cladosporium on FEV, same-day effects of Cladosporium spores on FEV was present across both seasons. Threshold effects of Alternaria on both PEF and FEV deficits were apparent at levels of 100 spores/m, but could not be explored for Cladosporium beyond the levels observed during the study.
The study provides evidence for the independent effects of daily exposure to ambient fungal spores of Alternaria and Cladosporium on lung function deficits, more especially in winter for PEF.
颗粒物（PM）的生物成分，如真菌孢子，对儿童肺功能的个体影响尚不清楚。本研究调查了每日交替变异性对南非西开普省非正规住区学生肺功能的短期影响。
本队列研究评估了 313 名南非西开普省非正规住区的学生，他们暴露于两种常见真菌——交链孢霉和枝孢霉的孢子中。这些孩子在夏季和冬季的两个连续的学校周内，每天三次提供 1 秒用力呼气量（FEV）和呼气峰流量（PEF）测量。全年在每个研究区域，使用空气质置监测器和孢子陷阱监测每日 PM 水平和真菌孢子水平。分析了交链孢霉和枝孢霉孢子对肺功能的影响，滞后期最长可达 5 天，调整了 PM、其他花粉暴露、研究区域和其他宿主及气象因素。计算了两种真菌的同天暴露反应曲线。
交链孢霉孢子水平的变异性更大，夏季出现明显峰值。与枝孢霉相比，交链孢霉对 PEF 的滞后效应更一致，冬季 PEF 最大缺陷（平均缺陷：13.78 L/min，95%CI：24.34 至-3.23 L/min）每增加 10 个交链孢霉孢子/m，在滞后第 2 天。虽然在 FEV 上没有观察到交链孢霉和枝孢霉的滞后效应，但在两个季节都观察到了同天枝孢霉孢子对 FEV 的影响。在 100 个孢子/m 的水平上，出现了交链孢霉对 PEF 和 FEV 缺陷的阈值效应，但无法在研究中观察到的水平之外，对枝孢霉进行探索。
本研究为每日暴露于环境真菌孢子的独立影响提供了证据，特别是在冬季，对 PEF 影响更明显。
