86
Water In Ecosystems: A Non Renewable Resource
I 'atrazine, la simazine, ou fa trifluraline ont une duree de vie suffisante pour etre
transportes sur plusieurs centaines de miles a partir des zones d' utilisation
jusqu'aux sites de reception OU ils contaminent [' eau par deposition seche ou
humide. Par contre, d'autres pesticides, tels que Ie diu ron, Ie carbaryl ou Ie
fenitrothion sont rapidement detruits lors de leur sejour dans l'atmosphere et ne
peuvent atteindre des zones eloignees.
On a procede simultanement a des mesures sur Ie terrain pour ce qui est des eaux
des lacs alpins en Savoie (France) afin de voir si ces pesticides etaient presents
dans la troposphere et dans les eaux des lacs alp ins. On a trouve des quantites
significatives d' atrazine, de simazine, de pendimethalin et de trifluralin dans l' air
et dans l'eau, alors que l'on n'a pas trouve de trace d'isoproturion, de diuron ni
de tenitrothion dans I 'atmosphere, ce qui etait conforme a leur duree de vie.
Cependant la presence de carbaryl dans les eaux des lacs est surprenante puisque
ce compose chimique a une duree de vie courte. Ces resultats preiiminaires seront
utilises pour etudier fa qualite de l'eau en paralWe avec les essais ecotoxicologiques et biochimiques.
1 INTRODUCTION
Because of technological progress modern societies produce greater and greater
amounts of exogenous or xenobiotic compounds, often referred to as anthropic
chemical compounds, since they are produced directly by human activity. The
major activities are industry, transport and modern agricultural practices.
The first and second of these activities are accompanied by fossil fuel combustion,
such as coal, fuel oil, heavy oil, petrol and diesel fuel combustion. All these forms
of combustion emit into the atmosphere chemical compounds, amongst which a
family of organic compounds particularly dangerous for human health because
they are often mutagenic and carcinogenic: PARs.
Some of these compounds are famous, such as BaP rightly considered to be the
most carcinogenic member of this family. These compounds are often resistant to
chemical and photochemical attacks, since they are unreactive with atmospheric
oxidants. They are hydrophobic and therefore poorly eliminated by rain and snow
events. Consequently, they can be transported over long distances from the source
zones - such as urban or industrial areas - towards the most remote regions of the
Earth, thus contributing markedly to the background pollution.
Furthermore, modern agricultural activity requires the use of fertilizers and
insecticides, designed to increase yields, and used in large quantities. Their main
purpose is to eliminate agricultural parasites.
In the same category, the upkeep of the road and rail networks requires the use of
herbicides, and the building industry uses fungicides. All these compounds, known
collectively as pesticides, also represent a danger for human health and for the
environment, since many of them are toxic. Some of these pesticides are rapidly
destroyed in the atmosphere by photochemical processes or are sufficiently
soluble to be found in the soils and in the surface water close to where they are
used.
Water In Ecosystems: A Non Renewable Resource
I 'atrazine, la simazine, ou fa trifluraline ont une duree de vie suffisante pour etre
transportes sur plusieurs centaines de miles a partir des zones d' utilisation
jusqu'aux sites de reception OU ils contaminent [' eau par deposition seche ou
humide. Par contre, d'autres pesticides, tels que Ie diu ron, Ie carbaryl ou Ie
fenitrothion sont rapidement detruits lors de leur sejour dans l'atmosphere et ne
peuvent atteindre des zones eloignees.
On a procede simultanement a des mesures sur Ie terrain pour ce qui est des eaux
des lacs alpins en Savoie (France) afin de voir si ces pesticides etaient presents
dans la troposphere et dans les eaux des lacs alp ins. On a trouve des quantites
significatives d' atrazine, de simazine, de pendimethalin et de trifluralin dans l' air
et dans l'eau, alors que l'on n'a pas trouve de trace d'isoproturion, de diuron ni
de tenitrothion dans I 'atmosphere, ce qui etait conforme a leur duree de vie.
Cependant la presence de carbaryl dans les eaux des lacs est surprenante puisque
ce compose chimique a une duree de vie courte. Ces resultats preiiminaires seront
utilises pour etudier fa qualite de l'eau en paralWe avec les essais ecotoxicologiques et biochimiques.
1 INTRODUCTION
Because of technological progress modern societies produce greater and greater
amounts of exogenous or xenobiotic compounds, often referred to as anthropic
chemical compounds, since they are produced directly by human activity. The
major activities are industry, transport and modern agricultural practices.
The first and second of these activities are accompanied by fossil fuel combustion,
such as coal, fuel oil, heavy oil, petrol and diesel fuel combustion. All these forms
of combustion emit into the atmosphere chemical compounds, amongst which a
family of organic compounds particularly dangerous for human health because
they are often mutagenic and carcinogenic: PARs.
Some of these compounds are famous, such as BaP rightly considered to be the
most carcinogenic member of this family. These compounds are often resistant to
chemical and photochemical attacks, since they are unreactive with atmospheric
oxidants. They are hydrophobic and therefore poorly eliminated by rain and snow
events. Consequently, they can be transported over long distances from the source
zones - such as urban or industrial areas - towards the most remote regions of the
Earth, thus contributing markedly to the background pollution.
Furthermore, modern agricultural activity requires the use of fertilizers and
insecticides, designed to increase yields, and used in large quantities. Their main
purpose is to eliminate agricultural parasites.
In the same category, the upkeep of the road and rail networks requires the use of
herbicides, and the building industry uses fungicides. All these compounds, known
collectively as pesticides, also represent a danger for human health and for the
environment, since many of them are toxic. Some of these pesticides are rapidly
destroyed in the atmosphere by photochemical processes or are sufficiently
soluble to be found in the soils and in the surface water close to where they are
used.