Yes, a covered conductor line can be used in polluted and salt-laden areas. APAR's covered conductor has an anti-tracking, UV-protected outer layer, and the product page lists resistance to pollution and salt among the conditions the outer jacket is designed to withstand. Polluted areas are named on the page as an application.
A bare conductor in the same location relies on insulator surfaces staying clean enough to hold off leakage, while the covering on a covered conductor reduces direct exposure of the live metal to deposits and moisture. Tracking resistance of the outer layer matters here, because surface leakage currents can otherwise cut a conductive path into the jacket over time.
Site conditions vary, so a coastal or industrial route should still be reviewed with the line designer. The site survey should record the pollution source, the distance from the sea and the existing insulator type.