Overview

• Officials from Bezirksamt Hamburg-Mitte detected a significant proliferation of blue-green algae in Öjendorfer See during routine testing.
• As of August 1, bathing and swimming on the north and south sides of the lake are banned until toxin concentrations fall below EU safety thresholds.
• The cyanobacteria produce cyanotoxins that can trigger skin and eye irritation, mucous membrane inflammation, allergic reactions and gastrointestinal distress.
• Under EU water quality directives, local health and environmental agencies perform regular and ad hoc assessments to guide timely swimming advisories and closures.
• Similar bans were imposed at lakes in Bavaria and Hesse earlier this summer as warm weather and nutrient enrichment fueled recurring algae blooms.