Fumes coming from a toilet at Berlin's Tegel airport on Saturday sickened 53 people, local media reported.
What kind of fumes? Apparently a cleaning crew used too much ammonia in cleaning the toilet overnight, according to TheLocal.de, an English-language news site in Germany.
"A high level of ammonia was measured," a police spokesman told Der Spiegel magazine.
Those who fell ill were treated for nausea and sore eyes, The Berliner Morgenpost reported.
Fire fighters who arrived at the scene to investigate the toilet also fell ill.
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