Coupled Application of Antioxidant Defense Response and Embryo Development in Amphipod Crustaceans in the Assessment of Sediment Toxicity

Abstract

Survival rate, frequency of malformed embryos, and antioxidant defense system responses in the benthic amphipod Gmelinoides fasciatus from the Baltic Sea were measured to examine the effects of toxic sediments, and to assess the usefulness of these endpoints in sediment toxicity biotesting. A highly contaminated sediment sample from the Baltic Sea was diluted with sediment from a clean site to come up with a series of 5 test sediments with dilutions from 1:32 to 1:1024, and the reference sediment. The 1:32 dilution of the test sediment was analyzed for organotins (2862 µg tin [Sn] kg dry wt –1), polycyclic aromatic hydrocarbons (6064 µg kg dry wt –1), and selected trace metals (e.g., copper 352 mg kg dry wt –1). The survival rate of G. fasciatus (10‐d toxicity test) was 100% in the reference and 1:1024 treatments, and began to decline from the 1:256 dilution onward. In a 28‐d experiment, various types of morphological malformations were observed in 11 to 80% of the amphipod embryos in the 1:64, 1:128, and 1:256 dilutions, with only <5% in the reference treatment. Also, elevated activities in the antioxidant defense system enzymes glutathione S‐transferase and catalase were observed in amphipods exposed to the contaminated sediments compared with the reference treatment, with responses at lower contamination levels compared with the appearance of malformations in the embryos. The results obtained illustrate the effectiveness of the combined application of embryonic malformations and antioxidant defense system biomarkers in amphipods in the assessment of sediment toxicity, and potentially also of sublethal effects of chemical contamination in aquatic ecosystems. Environ Toxicol Chem 2019;38:2020–2031. © 2019 SETAC.

Effects of Diclofenac on the Reproductive Health, Respiratory Rate, Cardiac Activity, and Heat Tolerance of Aquatic Animals

“…The embryo state as an endpoint of the toxic effects of hazardous substances has been actively developed during recent decades, based on Baltic amphipods (Gorokhova et al, 2018; Sundelin & Eriksson, 1998). The aberrations as delayed or stopped development of embryos have been less highlighted and interpreted than the appearance of malformed embryos, which is considered to be a result of toxic effects of heavy metals and organic pollutants (Berezina et al, 2019; Strode et al, 2017). As has been shown for the Baltic amphipod Monoporeia affinis , the frequency of embryo malformation in the brood is linked to the appearance of several types of DNA nucleoside adducts (epigenetic markers) that predict the elevated frequency of contaminant‐induced malformations in gravid females (Gorokhova et al, 2020).…”

“…After 7‐day acclimation to laboratory conditions, the females amphipods were with embryos at Stage 3 or 4 (before organogenesis). Stages were determined following Berezina et al (2019).…”

“…Under a stereomicroscope, the embryos were carefully removed from each female's marsupium with a strong trickle of water from a pipette. Healthy and aberrant embryos of G. fasciatus were recognized at stages of organogenesis (V–VIII) using the approach described previously (Berezina et al, 2019). The frequency of malformed embryos was calculated as a percentage by dividing the average number of malformed embryos by the total number of embryos in the female.…”

The behavioural and physiological ecology of embryos: responding to the challenges of life inside an egg

“…Up‐regulation of antioxidant components may neutralize ROS and thus reduce oxidative damage. For example, the embryos of amphipods elevate antioxidant enzyme activities of glutathione S‐transferase and catalase in response to contaminated sediments; and the embryos of mussels do the same when exposed to high levels of metals such as Cu and Ag (Boukadida et al ., 2017; Berezina, Lehtonen & Ahvo, 2019). When exposed to triclosan – a major surface water pollutant worldwide – embryos of zebrafish ( Danio rerio ) prevent oxidative damage through the induction of P glycoprotein efflux functionality and the activity of detoxifying/antioxidant enzymes (Parenti et al ., 2019).…”