No reports on the pollution levels here in Thessaloniki, but apparently the intense heat wave is causing pollution levels in Athens to soar above safe levels. According to this article from Kathimerini:
The level of large pollution particles in the air or PM10 emissions in Nea Smyrni, southern Athens, reached 320 mg/m3, surpassing the 240 mg/m3 safety level. High levels of particle emissions, blamed for cancer and respiratory problems, were also recorded in central and western Athens.
Ouch. My Athenian friends, take care.