It's common across the globe, eg:

  In 2023, 69.8 million litres of avgas were sold in Australia, releasing 39 tonnes of lead into the environment, predominantly around airports.

* https://bfpca.org.au/lead/

With any luck that will be curtailed "soon":

  The LEAD Group proposes the earliest possible date, certainly well before 2030, for leaded AvGas phaseout in Australia and looks to Europe for the mechanism of phasing it out.

  The lead additive for leaded fuel is called tetraethyllead (TEL).

  Leaded AvGas has a phaseout date of 2025 in the European Union because TEL has a 2025 sunset date in European Union countries.

* https://www.infrastructure.gov.au/sites/default/files/docume...