Multigenerational effects of carbendazim in Daphnia magna

Abstract

Carbendazim is a fungicide largely used in agriculture as a plant protection product. As a result of agricultural runoffs, drainage, and leaching, it reaches surface waters at concentrations possibly hazardous to aquatic communities. Because of potential and continuous release of carbendazim to aquatic systems, long-term exposure to aquatic organisms should be addressed. To fill the knowledge gap, the present study evaluated the responses of multiple generations of Daphnia magna (clone K6) to an environmentally relevant concentration of carbendazim (5 μg/L). Twelve successive generations were evaluated, and the effects in these offspring were compared with those from a control population. Neonates' fitness was assessed through immobilization, reproduction, and feeding activity tests, along with the comet assay for in vivo DNA damage evaluation. Recovery from long-term exposure was also assessed. In the F5 generation, the results revealed that when daphnids were re-exposed to carbendazim, DNA damage was higher in daphnids continuously exposed to carbendazim than those from clean medium. After daphnids were moved to a clean medium, a low recovery potential was observed for DNA damage. Daphnids exposed continuously for 6 generations (F6) to carbendazim displayed an increase in feeding rates when re-exposed to carbendazim compared with F6 daphnids reared in clean medium. Continuous exposure of daphnids to carbendazim induced a significant increase in DNA damage from the F0 to the F12 generation. Deleterious effects of the multigenerational exposure to carbendazim were more prominent at a subcellular level (DNA damage) compared with the individual level. Environ Toxicol Chem 2017;36:383-394. © 2016 SETAC.

Multigenerational effects of carbendazim in Daphnia magna: From a subcellular to a population level

“…In the study of Palanikumar et al (), the milkfish Chanos chanos was exposed to carbendazim and chlorpyrifos, and a possible relationship between DNA damage and fluctuation in antioxidant enzyme responses was found. Silva et al () also found an increase in DNA damage in D. magna from F0 to F12 using an approach similar to ours, with daphnids exposed to carbendazim in a multigenerational experiment, but a straight relationship between DNA damage and antioxidant enzymes could not be established.…”

“…During the multigenerational experiment, an isoclonal population of D. magna was exposed to 5 μg/L of carbendazim throughout 12 generations, with the intention of looking forward and testing the effects over a large temporal time scale. The choice of 12 generations allows a comparison with previous results (Silva et al ), and also takes account of the fact that this fungicide may be present for several months in the field because it is applied on different agricultural crops and at different times during the year (European Commission ). Simultaneously, a second isoclonal population of daphnids was maintained in clean medium and used as control.…”

“…It is considered persistent in the water layer (Cuppen et al ), and the maximum reported concentration was 4.5 μg/L in surface waters of the Traiguén River basin in Chile (Palma et al ). In addition, a previous multigenerational study has shown that DNA damage (genotoxicity) increased throughout generations of D. magna exposed to carbendazim (Silva et al ). Thus certain biomarkers may provide additional information on other mechanisms induced by carbendazim after long‐term exposures and may be useful for understanding effects at the individual and population levels.…”

Possible Enzymatic Mechanism Underlying Chemical Tolerance and Characteristics of Tolerant Population in Scapholeberis Kingi

“…3). Similarly, in previous studies, higher algal consumption in daphnids continuously exposed to lead or fungicides (carbendazim) over several generations has been observed (Araujo et al 2019;Silva et al 2017;Skjolding et al 2014), suggesting that increased food consumption accelerates gut clearance and helps detoxi cation. Thus, our ndings provide evidence that chemical-tolerant clones consume more energy to eliminate pollutants from their body.…”

Use of 5-azacytidine in a proof-of-concept study to evaluate the impact of pre-natal and post-natal exposures, as well as within generation persistent DNA methylation changes in Daphnia

“…This exposure setup can underestimate the adverse effects of chemicals as it excludes exposures during critical stages of development. As a result there is a recent shift in the academic community towards conducting multi-generational exposures for Daphnia , covering exposures during critical stages of development (Giraudo et al 2017 ; Jeong et al 2015 ; Silva et al 2017 ).…”