The smoke from Canada is causing poor air quality in Switzerland. Some measuring stations recorded values on Wednesday that are considered unhealthy. According to the Swiss environmental company IQAir, particulate matter pollution is particularly high. The concentration of PM2.5 particles, i.e. particulate matter with a diameter of less than 2.5 micrometres, at the Bern-Bollwerk measuring station on Wednesday afternoon was more than ten times the World Health Organisation's (WHO) annual guideline value. +Get the most important news from Switzerland in your inbox The concentration at numerous other measuring stations throughout Switzerland was also more than five times the annual guideline value - for example in Basel-Binnigen and Payerne. These fine particles are a health risk primarily due to their small size. The fine particles can penetrate deep into the respiratory tract and even into the blood. Overall, the environmental company categorised the air quality as "unhealthy" or ...
