Marine Ecosystems under Toxic Pressure - Vulnerability of Coastal Ecosystems and Adaptation - page 5

The species exploited (fishing, conchiliculture (the farming of
shellfish), the farming of sea vegetation, etc.) are also subject to these
pressures, which could explain certain recurrent weaknesses in the
immune system (F. Akcha, personal communication). Moreover,
exposure to pollutants can lead to a contamination of the biomass,
rendering it unfit for human consumption [LEB 06].
Once they have passed through the filters of lagoons, deltas and
estuaries, in which the levels of salinity trigger a significant
precipitation of matter, trapping certain components (cadmium in the
Gironde or in the Bay of the Seine, for example, among the most well-
known instances [SHI 13]), a proportion of the collection of
micropollutants issuing from the drainage basin are found in the
coastal zone (hydrocarbons, pesticides, metals, persistent organic
products, medication, cosmetics, etc.). For example, the supplies of
hydrocarbons to the marine environment account for 80% of the
telluric supplies, accidental pollution, therefore, only represents a
small fraction, of which the impact is mainly local and often
significant for macrofauna. At the end of the 1980s, the development
of chromatography in liquid form for environmental research, coupled
with mass spectrometry at high resolution, enabled hydrophilic
molecules of pharmaceutical, cosmetic or hygienic origin to be
gradually detected, at weak concentrations that qualify as emergent.
Pioneering studies have enabled the identification of a number of
these substances active in rivers, lakes and aquifers (for example, in
the United States [KOL 02]). In France, the first studies on coastal
waters and estuaries were only carried out quite recently [CAS 06].
Antibiotic and anti-inflammatory products, fungicides,
antidepressants, analgesics and anticancer medications have been
identified, of which it is still difficult to evaluate the real impact on
fauna and aquatic flora. More specifically, the use of the coast leads
locally to strong concentrations of cosmetic sun protection products,
oils and perfumes, as well as products used to protect the hulls of
boats from biological fouling (copper, tributyltin (TBT) and its
replacements). For example, at only 20 ng.L -1 , TBT considerably
disrupts the growing metabolism of mussels. At 2 ng.L -1 , TBT, an
endocrine disruptor, is capable of modifying the sex of certain marine