D10: Impact of Contaminants - Hydromod

Integrated Water Resource Management for Important Deep European Lakes and their Catchment Areas
EUROLAKES
D10: Impact of Contaminants
FP5_Contract No.: EVK1-CT1999-00004
Version: 4.0
Date: 25/07/01
File: D10-vers.4.0.doc
Page 136 of 136
One hypothesis is that the production of sertoli cells responsible for sperm production,
is being reduced by exposure to estrogenic and/or anti-androgenic chemicals during the
embryonic development. Since each sertoli cell produces only a fixed number of sperm,
their number are limit the number of sperm an adult man can produce. During male development
the pituritary gland secretes a follicle-stimulating hormone, which is suppressed
with increasing estrogen levels, thereby reducing sertoli cell formation [WWF
CANADA].
Dying of sea birds at Clear Lake (California)
Since the 50ies a massive reduction of Aechmophorus occidentalis population took
place. For the combat of mosquitoes the DDT related pesticide DDD was used several
times with a increasing dosage. In the fatty tissue of dead birds high concentrations of
DDD were found. Than a investigation of the fishes in the sea and the whole food chain
followed. The DDD was found in high concentrations as well in the planctonic algae. It
was also be ascertained that the pesticide is passed down from one generation to the
next in algae, fishes, birds, frogs and other organisms [GREENPEACE AUSTRIA].
Dying of peregrine falcons in Germany
Through Pesticide contaminated preys (DDT and other) the animals were poisoned and
their population increased in Germany and also on the whole northern hemisphere
since 1950. On the one hand the animals are poisoned through the preys, on the other
hand more and more clutches were lost because of brashly egg shells. This was the
reason of a hormone disruption of the calcium metabolism caused by pesticides
[GREENPEACE AUSTRIA].