I have not seen this mentioned before, so I'll just throw it out here
in 2010 there was an incident involving airbus 319, germanwings airlines.
On 19 December 2010 the Airbus A319 coming from Vienna, Austria, was on
approach to Köln/Bonn Airport, Germany. Turning on to the base leg the two pilots
noticed an abnormal smell. A short time later during intercept of the extended centre
line, both pilots noticed an adverse effect on their physical and cognitive
performance. They donned their oxygen masks and declared emergency. The Pilot in
Command (PIC) remained able to steer the airplane. The co-pilot felt he could no
longer perform his tasks in the cockpit without restrictions. After the landing and
having reached the parking position, both pilots sought medical treatment. Whereas
the PIC could resume his duties after four days, the co-pilot remained unfit to fly until
10 July 2011. The technical inspection of the aircraft did not reveal any indication of a
technical malfunction.
http://www.bfu-web.de/EN/Publication...ublicationFile