Do sewage treatment plant discharges substantially impair fish reproduction in polluted rivers?
Sewage treatment plants are frequently associated with the release of xenobiotics and, consequently, with alterations of the reproductive function induced by many of these substances in aquatic organisms. In order to assess the impacts of sewage treatment plant (STP) discharges in polluted rivers, two sentinel species (gudgeon Gobio gobio and stoneloach Barbatula barbatula) were caught during their reproductive cycle upstream and downstream two STPs (STP1--Goffontaine, STP2--Wegnez). Gonadosomatic index, histological (testicular and ovarian stages, atretic follicles, intersexuality) and endocrine (sex steroids, aromatase activity, alkali-labile phosphorus) parameters were assayed. In brief, the results revealed no systematic significant differences (p<0.05) between upstream and downstream sites, whatever the STP, species or sampling period. However, stoneloach females displayed some signs of reproductive impairment and endocrine disruption downstream STP1 (reduced GSI, oocyte diameter and ALP concentrations, increased proportion of atretic follicles) and STP2 (changes in gonadal aromatase activity and plasma levels of 11-KT and T). Few significant changes were observed for gudgeon males and females while there were no significant differences between upstream and downstream sites for stoneloach males. Moreover, plasma E(2) concentrations recorded in gudgeon males sampled in all sites were as high as in females and this was confirmed by high ALP levels. Besides, spermatogenesis of gudgeon males was delayed in STP1 upstream and downstream sites compared to the corresponding sites in STP2. These observations for gudgeon males do not seem related to STP discharge but to a probable estrogenicity of the river. Therefore, as shown by the results, stoneloach seemed more sensitive than gudgeon to STP discharges. In the present study, sewage treatment plant discharges do not substantially impair fish reproduction. In this respect, caution is required when generalising negative impacts of STP discharges.
Douxfils
Jessica
J
Unité de Recherches en Biologie des Organismes (URBO), Facultés Universitaires Notre-Dame de la Paix, Rue de Bruxelles, 61, B-5000, Namur, Belgium. jessica.douxfils@fundp.ac.be
Jessica
Douxfils
D
Mandiki
Robert
R
Robert
Mandiki
M
Silvestre
Frédéric
F
Frédéric
Silvestre
S
Bertrand
Arnaud
A
Arnaud
Bertrand
B
Leroy
Delphine
D
Delphine
Leroy
L
Thomé
Jean-Pierre
JP
Jean-Pierre
Thomé
T
Kestemont
Patrick
P
Patrick
Kestemont
K
D000818:Animals; D001141:Aromatase / Q000378:metabolism; D003531:Cypriniformes / Q000502:physiology*; D052244:Endocrine Disruptors / Q000009:adverse effects; D005260:Female; D012739:Gonadal Steroid Hormones / Q000097:blood; D008297:Male; D010053:Ovary / Q000473:pathology / Q000502:physiology; D012098:Reproduction; D045483:Rivers; D012722:Sewage; D013256:Steroids / Q000097:blood; D013737:Testis / Q000473:pathology / Q000502:physiology; D014819:Vitellogenins / Q000097:blood; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000009:adverse effects; D014876:Water Pollution / Q000009:adverse effects*
D052244:Endocrine Disruptors; D012739:Gonadal Steroid Hormones; D012722:Sewage; D013256:Steroids; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; D001141:Aromatase