While all surface waters in Slovenia failed to meet the standard for the level of mercury in fish, the Slovenian Environment Agency noted that the limit value set to protect fish-eating animals is 25 times stricter than the standard for safe food.

The value was exceeded at practically all measuring locations in Slovenia, including at those never exposed to direct mercury emissions. The problem is that mercury travels long distances, being also carried by polluted air and rainfall.

Similar results are also reported for other European countries, an exception being those who have not yet set up monitoring systems.

The same goes for brominated diphenylethers (BDE), which could be used the EU until 2004 in general household products (plastic, electricity and electronic equipment, textile) as a fire retardant. Like mercury, they persist in the environment for several decades.

Aside from these two problem substances, the general state of surface waters in Slovenia is good.

Still, after stricter standards for certain substances were introduced in 2016, specific spots are being given additional attention.

Acceptable levels of individual hazardous substances were exceeded after 2016 in the Meža river near Poklanec, in the Mura at Ceršak and Mota, in the Logaščica at Jačka, in the Podlomščica at Malo Mlačevo, in the Žabnik creek, in the Sava at Prebačevo, and in the Krupa near Klošter.

Meanwhile, encouraging findings have been made regarding the quality of the Slovenian sea, where the standards were met in 2017 for the level of tributyltin, which used to be employed for ship coatings.

Thus good chemical status has been established for the entire Slovenia sea.

Only Finland, Romania and Estonia have had a higher share of their rivers, lakes and coastal waters placed in the good chemical status category.