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Environmental relevant concentration of λ-cyhalothrin and 3-phenoxybenzoic acid caused endocrine-disrupting effects on male lizards (Eremias argus)
2020
Chang, Jing | Pan, Yifan | Yang, Lu | Xie, Yun | Xu, Peng | Wang, Huili
In the present study, the endocrine toxicity of LCT and PBA was investigated through exposure to Eremias argus for two weeks under environmental relevant concentration. RNA-sequencing identified 4442 and 4653 differentially expressed genes in lizard liver after LCT and PBA exposure. Four differentially expressed genes (hsd17β, ar, sult, ugt) related with hypothalamic-pituitary-gonadal axis were quantified by qPCR. The expression of genes associated with HPG axis in different tissues differed significantly. In LCT treatment group, ar, cyp17 and hsd3β genes involved in testosterone synthesis and transportation were significantly decreased in lizard testes, and the spermatogensis was inhibited in the testes, which indicated the anti-androgenic activity of LCT. After PBA exposure, the genes related with estradiol synthesis, transportation and metabolism, such as hsd17β, erα, ugt in lizard liver were important biomarkers and the significant decrease of estradiol level was highly correlated with hsd17β, erα, ugt gene expressions. The relative high binding affinity of PBA with ERα further demonstrated the anti-estrogenic activity of PBA. Our results elucidate the different toxic mechanism of LCT and PBA on lizard endocrine system at environmental relevant concentration. Pyrethroids metabolism may cause more seriously toxicity rather than detoxification.
Afficher plus [+] Moins [-]Coal combustion residues and their effects on trace element accumulation and health indices of eastern mud turtles (Kinosternon subrubrum)
2018
Cochran, Jarad P. | Haskins, David L. | Eady, Naya A. | Hamilton, Matthew T. | Pilgrim, Melissa A. | Tuberville, Tracey D.
Coal combustion is a major energy source in the US. The solid waste product of coal combustion, coal combustion residue (CCR), contains potentially toxic trace elements. Before 1980, the US primarily disposed of CCR in aquatic settling basins. Animals use these basins as habitat and can be exposed to CCR, potentially affecting their physiology. To investigate the effects of CCR on eastern mud turtles (Kinosternon subrubrum), we sampled 30 turtles exposed to CCRs and 17 unexposed turtles captured in 2015–2016 from the Savannah River Site (Aiken, SC, USA). For captured turtles, we (1) quantified accumulation of CCR in claw and blood samples, (2) used bacterial killing assays to assess influences of CCR on immune responses, (3) compared hemogregarine parasite loads, and (4) compared metabolic rates via flow-through respirometry between CCR-exposed and unexposed turtles when increased temperature was introduced as an added stressor. Turtles exposed to CCR accumulated CCR-associated trace elements, corroborating previous studies. Blood Se and Sr levels and claw As, Se, and Sr levels were significantly higher in turtles from contaminated sites. Average bacterial killing efficiency was not significantly different between groups. Neither prevalence nor average parasite load significantly differed between CCR-exposed and reference turtles, although parasite load increased with turtle size. Regardless of site, temperature had a significant impact on turtle metabolic rates; as temperature increased, turtle metabolic rates increased. The effect of temperature on turtle metabolic rates was less pronounced for CCR-exposed turtles, which resulted in CCR-exposed turtles having lower metabolic rates than reference turtles at 30 and 35 °C. Our results demonstrate that turtles accumulate CCR from their environment and that accumulation of CCR is associated with changes in turtle physiological functions when additional stressors are present.
Afficher plus [+] Moins [-]Contaminant exposure in terrestrial vertebrates
2007
Smith, P.N. | Cobb, G.P. | Godard-Codding, C. | Hoff, D. | McMurry, S.T. | Rainwater, T.R. | Reynolds, K.D.
Here we review mechanisms and factors influencing contaminant exposure among terrestrial vertebrate wildlife. There exists a complex mixture of biotic and abiotic factors that dictate potential for contaminant exposure among terrestrial and semi-terrestrial vertebrates. Chemical fate and transport in the environment determine contaminant bioaccessibility. Species-specific natural history characteristics and behavioral traits then play significant roles in the likelihood that exposure pathways, from source to receptor, are complete. Detailed knowledge of natural history traits of receptors considered in conjunction with the knowledge of contaminant behavior and distribution on a site are critical when assessing and quantifying exposure. We review limitations in our understanding of elements of exposure and the unique aspects of exposure associated with terrestrial and semi-terrestrial taxa. We provide insight on taxa-specific traits that contribute, or limit exposure to, transport phenomenon that influence exposure throughout terrestrial systems, novel contaminants, bioavailability, exposure data analysis, and uncertainty associated with exposure in wildlife risk assessments. Lastly, we identify areas related to exposure among terrestrial and semi-terrestrial organisms that warrant additional research. Both biotic and abiotic factors determine chemical exposure for terrestrial vertebrates.
Afficher plus [+] Moins [-]Monitoring temporal and spatial trends of legacy and emerging contaminants in marine environment: Results from the environmental specimen bank (es-BANK) of Ehime University, Japan
2012
Tanabe, Shinsuke | Ramu, Karri
The Environmental Specimen Bank (es-BANK) for Global Monitoring at the Center for Marine Environmental Studies, Ehime University, Japan has more than four decades of practical experience in specimen banking. Over the years, es-BANK has archived specimens representing a wide range of environmental matrices, i.e. fishes, reptiles, birds, aquatic mammals, terrestrial mammals, human, soils, and sediments. The samples have been collected as part of the various monitoring programs conducted worldwide. The current review is a summary of selected studies conducted at the Center for Marine Environmental Studies, on temporal and spatial trends of legacy and emerging contaminants in the marine environment. One of the major conclusions drawn from the studies is that environmental problems are no more regional issues and, thus, environmental specimen banking should not be limited to national boundaries, but should have a global outlook.
Afficher plus [+] Moins [-]A review of ghost gear entanglement amongst marine mammals, reptiles and elasmobranchs
2016
Stelfox, Martin | Hudgins, Jillian | Sweet, Michael
This review focuses on the effect that ghost gear entanglement has on marine megafauna, namely mammals, reptiles and elasmobranchs. A total of 76 publications and other sources of grey literature were assessed, and these highlighted that over 5400 individuals from 40 different species were recorded as entangled in, or associated with, ghost gear. Interestingly, there appeared to be a deficit of research in the Indian, Southern, and Arctic Oceans; and so, we recommend that future studies focus efforts on these areas. Furthermore, studies assessing the effects of ghost gear on elasmobranchs, manatees, and dugongs should also be prioritised, as these groups were underrepresented in the current literature. The development of regional databases, capable of recording entanglement incidences following a minimum global set of criteria, would be a logical next step in order to analyse the effect that ghost gear has on megafauna populations worldwide.
Afficher plus [+] Moins [-]Assessment and rehabilitation of wildlife affected by an oil spill in Puerto Rico
1999
Mignucci-Giannoni, A.A. (Red Caribena de Varamientos, Caribbean Stranding Network and University of Puerto Rico, PO Box 361715, San Juan, 00936 (Puerto Rico))
Effects of DDT ground-spraying against tsetse flies on lizards in NW Zimbabwe
1993
Lambert, M.R.K. (Natural Resources Institute, Central Avenue, Chatham Maritime, Chatham, Kent, ME4 4TB (United Kingdom))
Influence of pesticides in reproductive aspects of Tropidurus torquatus in Minas Gerais, Brazil
2021
de Almeida, Filipe Gomes | Guimarães, Luiza Soares Ferreira | Fonseca, André de Oliveira | de Oliveira, Paola Rosa | da Silva Mendes, Sarah
Intense agricultural activity in recent years has resulted in a greater use of pesticides in order to improve productivity. However, these pesticides may contain some pollutant component in their composition. Once present in the environment and/or in excess, they can cause damage to the local flora and fauna. The aim of this study was to evaluate the interference of pesticides in the reproductive aspects of male and female specimens collected in two distinct sampling sites and propose a methodology to investigate pesticide effects associated with the reproduction at a macroscopic level for reptile specimens from zoological collection. The results showed that males located in the area with the use of agricultural pesticides had a lower testicle volume compared with the ones located in the area that did not use pesticides. However, no difference was found regarding the volume of eggs compared at the same stage and the average clutch size of each population. Therefore, the present study indicates the analyzed pesticides might influence the reproduction of the studied males. Despite no evident alterations in egg volume and quantity in the area with pesticide use, our findings suggest further studies on the structure and composition of eggshell and yolk in order to assess the effects of pesticides on their viability.
Afficher plus [+] Moins [-]Comparative Study of Lead Accumulation in Different Organs of the Freshwater Crab Zilchiopsis oronensis
2012
Gagneten, Ana María | Tumini, Georgina | Imhof, Alba | Gervasio, Susana
Lead (Pb) is known as an important aquatic contaminant with different toxic effects on various organisms. Until now, only few quantitative investigations have been published comparing Pb content in different organs of adult freshwater crabs. Their capacity to bioaccumulate other heavy metals is already known, and they can potentially transfer Pb to the terrestrial systems, as they are frequent trophic items of reptiles and birds, even humans. The objectives of this study were to assess Pb accumulation in the gills, carapace, digestive gland, and quela muscle of the freshwater crab Zilchiopsis oronensis, and to correlate bioaccumulation with morphometric data and sex. The crabs were manually caught in unpolluted ponds of the middle Paraná River alluvial valley (Santa Fe, Argentina). After the acclimation period, they were individually and randomly exposed per quadruplicate to three Pb experimental doses: 20, 40, and 80 mg Pb/L, in plastic cages during 15 days. After dissecting the crabs, the tissues were analyzed for lead in a Perkin Elmer Analyst 800 atomic absorption spectrometer. We found significant differences (p < 0.05) between the control and each one of the treatments but not between treatments (p > 0.05) and highly significant differences (p < 0.0001) between Pb concentration in organs. The Tukey posttest showed significant differences (p < 0.05) between gills–carapace, gills–digestive gland, and gills–quela muscle. The weight of the crabs only showed a negative correlation with Pb in the quela muscle (r = −0.53; p = 0.03). Pb in the carapace (but not in the other tissues) was positively correlated with the width (p = 0.571) and length (p = 0.616). Males accumulated more Pb than females, though not significantly. The present paper is aimed to contribute to our knowledge on Pb accumulation in freshwater crabs and select the better indicator organisms for biomonitoring.
Afficher plus [+] Moins [-]Plasma B-esterase and Glutathione S-transferase Activities in the South American Reptiles Caiman latirostris (Crocodylia, Alligatoridae) and Phrynops hilarii (Testudines, Chelidae)
2012
Attademo, Andrés M. | Lajmanovich, Rafael C. | Peltzer, Paola M. | Bassó, Agustín | Junges, Celina | Cabagna-Zenklusen, Mariana
We determined normal plasma butyrylcholinesterase (BChE), carboxylesterase (CbE using α-NA substrate), and glutathione S-transferase (GST) activities in Caiman latirostris and Phrynops hilarii to obtain reference values for organophosphorus (OP) pesticide monitoring. BChE and CbE sensitivity to malaoxon was also evaluated. C. latirostris (N = 12; six males and six females) and P. hilarii (N = 12; seven males and five females) were obtained from the programs Yacaré (Entre Ríos Province, Argentina) and Zoo of Córdoba (Córdoba Province, Argentina). Mean total (female and male) plasma BChE activity was significantly different between reptile species, ranging between 0.337 ± 0.085 μmol min−1 ml−1 of plasma for C. latirostris and 0.251 ± 0.070 μmol min−1 ml−1 of plasma for P. hilarii. However, plasma CbE (α-NA) and GST activities were significantly higher in P. hilarii (4.81 ± 1.00 and 0.145 ± 0.045 μmol min−1 ml−1 of plasma, respectively) than in C. latirostris (0.57 ± 0.20 and 0.059 ± 0.013 μmol min−1 ml−1 of plasma, respectively). No significant differences in B-esterase and GST activities were detected between sexes, except CbE (α-NA) for C. latirostris. IC50 values for BChE and CbE (α-NA) suggested different sensitivity levels between species and between sexes. The results demonstrate that plasma esterase activity varied between species, but not between sexes (except CbE for C. latirostris). The in vitro inhibition tests indicated that CbE (α-NA) is more sensitive to inhibition than BChE. C. latirostris may be the reptile species most vulnerable to field pesticide exposure because this reptile presents the lowest CbE activity levels and its B-esterase levels seem more sensitive to OP.
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