The impact of successive COVID-19 lockdowns on people mobility, lockdown efficiency, and municipal solid waste.

The COVID-19 pandemic has induced many issues for all societal sectors, in particular in the production and disposal of municipal solid waste. This may be because successive easing and reimposing of lockdown measures have deeply changed people's movements, consumers' behaviors and waste management. Previous studies have focused on the short-term effects of lockdowns on waste changes, yet there is little knowledge on waste variations during successive lockdowns and unlocking of various lockdown intensities. Moreover, the efficiency of lockdown and its relation to people's mobility in different countries are still not clear. Here, we studied the variations of amount and composition of municipal solid waste before the pandemic in 2019 and during the pandemic in 2020-2021 in USA, Brazil, Canada, UK, France and Italy. We used a stringency index and a composite mobility index to assess the lockdown intensity and people's movements. Results show that the mobility index sharply decreased with lockdown intensity, and enforcing measures were more efficient in France and Italy. Compared to 2019, prolonged lockdowns caused larger decreases in the quantity of commercial and construction wastes versus household waste. The initial implementation of lockdown or unlocking measures promoted inhabitants' consumption, generally leading to the increased waste amount, by about 9% for Trento and 12% for Montreal at the beginning of lockdown, respectively. Moreover, larger variations in the waste amount in Trento, from - 25.3 to 9.8%, were in line with higher lockdown intensity compared to those in Montreal, from - 9.5 to 12.7%, affected by people's mobility, consumers' behaviors and waste management. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10311-021-01290-z.