"When
volunteers worked in well-ventilated conditions (which lowered the levels of CO2 and
VOCs), they scored 61% higher than when they worked in a typical office building
conditions. When they worked in the cleanest conditions, with even lower CO2 levels
and higher ventilation rates, their scores climbed 101%" https://www.sciencemag.org/news/2021/08/scientist-says-cleaning-indoor-air-could-make-us-healthier-and-smarter?utm_campaign=news_daily_2021-08-05&et_rid=385360185&et_cid=3872970
A Scopus search by publications having "indoor air" in the title retrieves 8649 documents. The first publication is from the year 1908, but since that date until 1976 (almost 70 years) was responsible only for 0.6% meaning that more than 99% of the publications took place in the last 45 years, and more than 40% just in the last ten years. Unfortunately, there´s not a single European university in the top three affiliations with more publications, US EPA, Hong Kong Polytechnic University and Tsinghua University.
PS - On indoor ventilation check the botanical biofiltration systems mentioned in here https://pacheco-torgal.blogspot.com/2020/03/coronavirus-biodiversity-hypothesis.html
