Drug residues 'alter fish behaviour' Psychiatric drugs taken by
humans to cope with anxiety are being excreted and flushed into
waterways where they are probably affecting fish behaviour. This
is the conclusion of a new Swedish study reported in Science
magazine. The Umea University-led investigation exposed
laboratory perch to the drug Oxazepam at levels equivalent to
the residues found in rivers and streams. The fish were found to
eat faster, to be less social and to be bolder than animals that
were not dosed. Umea’s Tomas Brodin said the behavioural changes
seen in their lab animals could have unexpected evolutionary and
ecological consequences if reflected in wild populations. “The
strong behavioural modifications we saw were at low
concentrations, and I firmly believe we could go even lower and
still see these effects,” the researcher told BBC News. “We
looked at just one benzodiazepine-type drug but there are many
others out there, and they probably all have the same effects on
fish and other vertebrate