Alterations to embryonic development and teratogenic effects induced by a hospital effluent on Cyprinus carpio oocytes

Abstract

Hospital functioning generates a great quantity of contaminants, among which organic materials, heavy metals, and diverse pharmaceuticals are noteworthy that can affect organisms if they are not properly removed from the effluents. The hospital effluent evaluated in the present study came from IMSS (Instituto Mexicano del Seguro Social) Clinic 221 in downtown Toluca, State of Mexico, a secondary care facility. The contaminants identified in hospitals have been associated with deleterious effects on aquatic organisms; however, it is necessary to continue with more studies in order to be able to regulate the production of said contaminants which are generally dumped into the city sewage system. The present study had the purpose of evaluating the alterations to embryonic development and teratogenic effects on oocytes Cyprinus carpio after exposure to different proportions of hospital effluent. For said purpose, the physicochemical properties of the effluent were determined. Concentrations of the main microcontaminants were also determined. An embryolethality study out and the determination of the main alterations to embryonic development and teratogenic effects produced, due to exposure of C. carpio at different proportions of the effluent, were carried out. The results showed that the physicochemical properties were within the values permitted by Mexican regulation; however, the presence of contaminants such as NaClO, metals, anti-biotics, anti-diabetics, non-steroidal anti-inflammatory drugs, hormones and beta-blockers, was detected. Lethal concentration 50 was 5.65% and the effective concentration for malformations was 3.85%, with a teratogenic index of 1.46. The main teratogenic alterations were yolk deformation, scoliosis, modified chorda structure, tail malformation, fin deformity and mouth hyperplasia. A high rate of hatching delay was observed. The results suggest that the hospital effluent under study is capable of inducing embryotoxicity and teratogenicity in oocytes of C. carpio.

Keywords: Common carp; Embryotoxicity; Emerging contaminants; Hospital wastewaters; Teratogenicity.