Hungarian and International Regulations of Cyanobacterial Toxins, with Special Regard to Lake Balaton as a Drinking Water Supply

Abstract

A new drinking water directive, 2020/2184/EU issued in December 2020, contains limit values for cyanobacterial toxins, among other new requirements. The aim of this study is to summarise data available about the effects imposed on drinking water supplies by algal blooms and cyanobacteria and to compare international regulations in order to analyse deficiencies and possible solutions
for Hungary. Although the water quality of Lake Balaton improved after the millennium, algal blooms under extreme environmental conditions drew attention to this ever present problem. Based on international literature and on the examination of the state of drinking water supply from the Balaton, it can be concluded that EU and domestic regulations are less detailed compared to other countries, which are more affected by issues related to cyanobacteria. However, it is not expected that Hungarian conditions will require stricter regulations in the future, because of the
professional operational culture and the planned development in the water utilities sector, which will eliminate the root of the problem, that is, surface waters exposed to cyanobacteria will not be used as drinking water resources.