Biochemical and morphological responses in Chironomus riparius (Diptera, Chironomidae) larvae exposed to lead‐spiked sediment

Abstract

The aim of the present study was to assess the potential use of biochemical markers and mentum deformities as indicators of long‐term exposure to lead (Pb) in Chironomus riparius larvae. To do this, the authors measured 3 biochemical markers (i.e., malondialdehyde level, metallothionein concentration, and energy reserve content) as well as larval growth and mentum deformities after 16‐d exposure to sediment containing Pb. The concentrations studied ranged from 3.5 mg/kg to 505.5 mg/kg dry weight. Despite the bioaccumulation of Pb in C. riparius bodies, frequencies of both mentum deformities and the dry weight were not significantly different between the control and stressed groups. On the contrary, Pb exposure caused a significant increase of both malondialdehyde level and metallothionein concentration. The increase of body Pb concentrations did not significantly modify body copper and zinc concentrations. Moreover, we observed a decrease of total lipid content and an increase of glycogen content as a function of a dose–response relationship, while no variation in protein concentrations was observed. Despite the adverse effects observed at the biochemical level, larval development was not affected. These results suggested that measurements of malondialdehyde level, metallothionein concentration, and energy reserve content can be used as relevant biomarkers of long‐term sublethal exposure to Pb in C. riparius larvae. Environ Toxicol Chem 2013;32:2558–2564. © 2013 SETAC

Mercury tissue residue approach in Chironomus riparius: Involvement of toxicokinetics and comparison of subcellular fractionation methods

“…Considering the combined exposure to contaminated water (6.9 g Hg L −1 ) and sediments (1.3 g Hg g −1 ), these results are in agreement with the literature data since toxicity bioassays with C. riparius reported EC 20 for growth ranging between 7.5 and 50.3 g Hg L −1 in water and between 1.8 and 3.2 g Hg g −1 in sediments (Chibunda, 2009;Azevedo-Pereira and Soares, 2010). This may be interpreted as the result of a toxic effect of Hg bound-HSP affecting, for instance, lipid peroxidation (Arambourou et al, 2013) or protein functioning and synthesis (Barka et al, 2001). However, regarding the intense Hg trafficking at the subcellular level, this growth impairment could also be attributed, referring to the DEBtox theory (Kooijman et al, 2009), to a change in the energetic allocation between somatic maintenance (excretion and/or detoxification processes) and growth.…”

Low dietary levels of Al, Pb and Cd may affect the non-enzymatic antioxidant capacity in caged honey bees (Apis mellifera)

“…3D). Recently Arambourou et al (2013) exposed chironomids to Pb (3.5e505.5 mg/kg) for 16 days and found a significant increase in MT and a metal accumulation in insect tissues beyond 500 mg/kg. In our study, the highest Pb concentration was 0.3 mg/kg and an accumulation of up to 0.08 mg/bee was observed.…”

Effects of the boscalid fungicide Filan® on the marine amphipod Allorchestes compressa at environmentally relevant concentrations

“…This proposal was supported by David et al , who reported a significant reduction in total, soluble, and structural proteins in deformed tadpoles of Duttaphrynus melanostictus exposed to sublethal concentrations of cypermethrin. On the contrary, Arambourou et al reported alterations in energy reserves of C. riparius exposed to lead‐spiked sediment, but no mentum morphological defects were observed.…”