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«"Les"polluants"organiques"persistants"(POP)"ont"été"largement"reconnus"comme"une"menace"pour"la"
santé"humaine"et"les"écosystèmes."Ils"sont"utilisés"comme"pesticides"ou"ingrédients"dans"la"fabrication"
de" produits" industriels" tels" que" les" solvants" et" les" polychlorures" de" vinyle" (PVC)," les" biphényles"
polychlorés" (BPC)" et" les" dioxines" ainsi" que" deux" pesticides" interdits," le" chlordane" et" le"
dichlorodiphényltrichloroéthane"(DDT)."Bien"que"toxique,"le"PVC"se"retrouve"partout,"car"cette"matière"
plastique"très"solide"peut"aussi"bien"servir"à"fabriquer"des"fenêtres"et"autres"structures"qu'être"assouplie"
pour" devenir" vêtements,"bateaux"pneumatiques,"tissus"d'ameublement," etc." Même" après" l'interdiction"
des"BPC,"du"DDT"et"autres"contaminants,"leurs"résidus"restent"présents"dans"l'environnement."
Les"contaminants"peuvent"se"frayer"un"chemin"jusqu'à"nos"assiettes"par"la"voie"des"fruits"de"mer"et"des"
poissons."Du"fait"que"la"plupart"de"ces"produits"chimiques"complexes"sont"persistants"et"solubles"dans"les"
lipides,"ils"ont"de"fortes"chances"de"durer"longtemps"dans"le"milieu"aquatique"en"s'accumulant"dans"le"
tissu"adipeux"des"poissons"et"autres"animaux"aquatiques."Les"chercheurs"ont"découvert"que"la"chair"de"
certains"poissons,"qu'ils"soient"issus"de"la"pisciculture"ou"de"l'océan,"contenait"des"composés"organiques"
produits"par"l'homme."Des"substances"toxiques"persistantes"et"des"métaux"lourds,"comme"le"plomb,"ont"
été" trouvés" dans" des" poissons" et" des" fruits" de" mer" provenant" de" lacs" et" de" zones" côtières" du" monde"
entier,"comme" les"poissons"et" les"moules" de"la"Baltique,"les"eaux"d'Asie"du"SudQest"et"les"Grands"Lacs"
situés"entre"les"ÉtatsQUnis"et"le"Canada.""
Source":http://www.notreQplanete.info/environnement/eau/eau_contamination.php"
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BIOACCUMULATION,! BIOCONCENTRATION! ET! BIOAMPLIFICATION! DES!
CONTAMINANTS!
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Un" polluant" qui" est" en" faible" quantité" dans"
l’environnement"et"qui"semble"inoffensif"au"début"de"la"
chaine" trophique" peut" s’avérer" toxique" en" bout" de"
chaine."Le"problème"s’amplifie"!""
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"B5=N1<"("US"Environmental"Protection"Agency"

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