August 2021. Mariupol, Ukraine. The beach front right next to the Azovstal steelworks. In 2018 Ukraine's Health Ministry warned the public to avoid swimming at any of the beaches around Mariupol. Mariupol residents are exposed to 10 times more industrial pollution than the average Ukrainian. Itâs the second most-polluted city in Ukraine, according to the Central Geophysical Observatory, a state agency.