Abnormalities in Sexual Development of the Amphipod Gammarus Pulex (L.) Found Below Sewage Treatment Works

Abstract

Increasing numbers of widely used industrial, agricultural, and natural chemicals are known to elicit endocrine-disrupting effects in a wide range of vertebrate and invertebrate species. The objective of this study was to determine whether the sexual development of the freshwater crustacean Gammarus pulex (L.) was affected below sewage treatment works (STW) previously known to contain endocrine-disrupting chemicals in their effluent. The gonadal structure, external sexual characteristics, and size of gammarids from exposed sites were compared to those of gammarids from a reference site. No significant difference was found in the gonadal structure of males collected below two STW. However, a highly significant number of females collected from a site known to elicit high estrogenic responses in vertebrates displayed an abnormal structure of oocytes in vitellogenesis. Body size was significantly shorter and male/female size differential was significantly reduced below one of the STW. Analysis of gnathopod and genital papillae length data suggests that different allometric relationships of these organs to body size exist between sample sites.

Review of the reproductive biology of amphipods and their endocrine regulation: Identification of mechanistic pathways for reproductive toxicants

“…Sundelin and Eriksson [70] reported high frequencies of malformed embryos in the deposit-feeding amphipod M. affinis, in which high concentrations of polycyclic aromatic hydrocarbons were measured in settling particulate matter and bottom sediments. An abnormal structure of oocytes in vitellogenesis was reported for the amphipod G. pulex sampled at river sites where the natural steroids 17b-estradiol and estrone had been detected, together with male fish producing vitellogenin, a typical biomarker of exposure to estrogenic substances [116]. However, the cause of the pathologies in G. pulex is uncertain because, in the laboratory, crustaceans (crabs and shrimps) did not produce vitellin in response to estrogens [117].…”

Endocrine disruption in the shore crab Carcinus maenas—a biomarker for benthic marine invertebrates?

“…Gross et al (2001) reported that high numbers of females displayed abnormal vitellogenic oocytes and a reduced male/female size differential in amphipods (Gammarus pulex) found below sewage treatment works known to contain endocrine-disrupting chemicals in their effluent.…”

“…Other examples of effects in invertebrates include abnormal levels of intersexuality in several species of marine harpacticoid copepods along sewage-contaminated coasts of Scot-land (Moore & Stevenson 1991, 1994, the occurrence of intersex in a population of lobsters exposed to sewage effluent (Sangalang & Jones 1997), masculinisation of freshwater copepod species in North American lakes (Sillett & Stemberger 1998) and the presence of dual-gender imposex in freshwater crabs inhabiting Japanese TBT-uncontaminated mountain streams (Takahashi et al 2000). Gross et al (2001) reported that high numbers of females displayed abnormal vitellogenic oocytes and a reduced male/female size differential in amphipods (Gammarus pulex) found below sewage treatment works known to contain endocrine-disrupting chemicals in their effluent.…”

Mysid crustaceans as standard models for the screening and testing of endocrine-disrupting chemicals

“…Morphological and histological changes resulting from exposure to EDs have been documented in fish, amphibians, reptiles, mammals, and arthropods (e.g., Gross et al, 2001;Vandenbergh et al, 2003;Schirling et al, 2006). In mysids, morphology and histology have not been considered widely as a measurable endpoint in toxicological studies.…”