Serious mercury pollution in the vicinity of Spolana neratovice has already been described in several studies.
Arnika measured high levels of mercury in the air near the sites of both chemical plants (Arnika-toxic substances and wastes 2006). Even more visible is the long-term Mercury load in the measurement results (Suchara and Sucharová 2008) in oak bark (see map in Figure 1).

Vice: https://ipen.org/sites/default/files/t/hgmonitoring/pdfs/czech_republic-report-cz.pdf