Evaluation of genotoxicity in Rhamdia quelen (Pisces, Siluriformes) after sub-chronic contamination with Fipronil

Abstract

Diverse genetic biomarkers have been used to evaluate the effects of pollution by mutagenic agents such as metals and pesticides, as well as a large variety of chemical substances derived from human activities. This work researched the effects that an exposure of 60 days to the insecticide Fipronil (concentrations of 0.05, 0.10 and 0.23 μg/L) can cause in the fish Rhamdia quelen using Comet assay with gills, histopathological analysis of gills and the Piscine Micronucleus test and Nuclear Morphological Alterations. The results for the Comet assay and for gills histopathological injuries showed no difference between the control group and the contaminated groups. In the Piscine Micronucleus test, the smallest concentration of Fipronil (0.05 μg/L) was similar as the control group, while concentrations of 0.10 and 0.23 μg/L caused more damage to the DNA. These results suggested that only the highest concentrations of Fipronil tested cause damage in erythrocytes, but none of these concentrations was sufficient to alter the DNA in the gill cells. R. quelen may be a less sensitive bioindicator than other fish that have been tested. On the other hand, the concentrations used may not have been sufficient to detect alterations in the DNA of R. quelen with the chosen tests. Works like this take on great importance given the enormous quantity of substances that are thrown daily into the environment in an uncontrolled way, without evaluation of the consequences. The application of these tests with other concentrations, tissues and exposure times is suggested for future works.

Fipronil promotes motor and behavioral changes in honey bees (Apis mellifera) and affects the development of colonies exposed to sublethal doses

“…France, Italy, Germany, and Slovenia, to ban its use [41]. The results presented in our study demonstrate the threat of fipronil to A. mellifera and verify that it causes motor and behavioral changes.…”

In Vitro Genotoxicity of Fipronil Sister Chromatid Exchange, Cytokinesis Block Micronucleus Test, and Comet Assay

“…Ghisi et al (2011) researched the effects of exposure of 60 days to the insecticide FP (concentrations of 0.05, 0.10, and 0.23 mg/L). They found that two concentrations-0.10 and 0.23 mg/L-of FP exposure caused the histopathological changes, nuclear morphological alterations, and DNA damage on the gills in R. quelen using the histopathologic analysis and the MN test/comet assay.…”

“…Studies performed in rats explained that FP is quickly metabolized and residues are distributed in tissues, especially in fatty tissues under the skin and hair follicles (Hugnet et al, 1999). Ghisi et al (2011) evaluated the genotoxicity of FP in Rhamdia quelen after subchronic contamination at three different concentrations (0.05, 0.1, 0.23 mg/L) using the comet and micronucleus (MN) test. They found that both 0.1 and 0.23 mg/L concentrations caused the most damage on DNA.…”

Evaluation of Motor Changes and Toxicity of Insecticides Fipronil and Imidacloprid in Africanized Honey Bees (Hymenoptera: Apidae)

“…The use of the systemic insecticides fipronil and imidacloprid was banned in France, Italy, Germany, Slovenia (Ghisi et al, 2011), and Uruguay (Pareja et al, 2011) due to the high toxicity of these pesticides to pollinators. In Brazil, the authorization of the use of imidacloprid is under review process, and the aerial application of neonicotinoids (imidacloprid, tiamethoxam, clotianidine) and fipronil are forbidden in flowering crops (Ministério da Agricultura, Pecuária e Abastecimento, 2013).The review of the use authorization of fipronil and imidacloprid in countries where these products are authorized, such as Brazil, is important to reduce the risk that these substances represent to honey bees, whose loss affects beekeeping and compromises the survival and maintenance of native pollinators.…”