Marine Debris and Trace Metal (Cu, Cd, Pb, and Zn) Pollution in the Stranded Green Sea Turtles (Chelonia mydas)

Marine debris and trace metals are among the common environmental contaminants known to affect marine organisms. In this study, the quantitative and qualitative aspects of marine debris levels and bioaccumulation of trace metals (Cadmium: Cd; Copper: Cu; Lead: Pb; and Zinc: Zn) were investigated in 42 green sea turtles (Chelonia mydas) stranded on the northern coast of the Sea of Oman. The greatest quantity of debris was found in the intestine, stomach, and esophagus of the animals, respectively. Results of a Marine Strategy Framework Directive (MSFD) subcategory analysis of the ingested debris showed that sheet and thread-like plastics were the most frequently detected debris followed by various rubbish. The results revealed that white-colored debris were the most common debris, followed by black > green > blue > transparent > and brown ones. The results suggested that the rope monofilament was the main source of the ingested debris by the green sea turtles. Concentrations of the trace metals in the liver, kidney, and muscle ranged between 0.66-33.43, 0.36-15.12, and 0.33-7.47 μg/g (ww), respectively. The results of this study suggest that ingested marine debris and tissue concentrations of trace metals are present at levels that may cause sublethal effects on green sea turtles (C. mydas) through potentially affecting the physiological processes and making the turtles susceptible to other natural or human threats. Results indicated that the green sea turtles from the northern coast of the Sea of Oman have high interaction with the marine debris. These factors are considered as a serious threat to the existence and survival of the green sea turtles (C. mydas) living on the northern coast of the Sea of Oman.

Polycyclic aromatic hydrocarbons (PAHs) and some biomarkers in the green sea turtles (Chelonia mydas)

Selected blood biochemical parameters (Glutathione S transferase: GST; Alanine aminotransferase: ALT; Aspartate aminotransferase: AST; Lactate dehydrogenase: LD and glucose) and polycyclic aromatic hydrocarbons (PAHs) were measured in blood samples from 18 green sea turtles (Chelonia mydas) from the Iranian coastline on the northern shore of the Sea of Oman. Mean total PAH concentration in the blood samples was 17.802 ± 1.006 ng/gdw. The study found no significant correlation between blood biochemical parameters and PAHs (p > 0.01), however significant correlations were found between total PAHs and GST activity (p < 0.01). The GST activity measured in this study was useful as a first investigation into the biological effects of PAH pollution as well as in determining the bioavailability of pollution. The results suggest that PAHs might be a factor influencing a reduction in green sea turtle egg fertilization and hatching success. Further study is needed concerning the effects of PAHs and other pollutants on green sea turtles, and specifically on the potential impact on the fetal development of green sea turtles.

Toxicity and Mechanisms of Action of Polycyclic Aromatic Hydrocarbon Pollution in Red Algae (Gracilaria corticata) from the Northern Coast of the Oman Sea

The activities of selected biomarkers including 7-ethoxycoumarin-O-deethylase (ECOD) and glutathione S-transferase (GST) were measured in the red algae (Gracilaria corticata) obtained from the Oman Sea. Chemical analyses were used to assess the polycyclic aromatic hydrocarbons (PAHs) in the red algae. Total PAH concentrations in the red algae ranged from 3.61 to 8.14 ng g^-1 dry weight. Mean GST and ECOD activity also varied from 8.87 to 15.32 nmol/mg protein/min and from 0.31 to 1.02 pmol/min/mg protein, respectively. Significant correlations were found between the total PAH levels and the selected biomarkers (p < 0.01). The results showed that ECOD and GST enzymes reacted to PAHs in phase I and II detoxification mechanisms of red algae (G. corticata), which extend the use of these biomarkers for investigation of the biological effects of PAH pollution as well as determination of pollution bioavailability. Environ Toxicol Chem 2019;38:1947-1953. © 2019 SETAC.

Application of biomarkers in brown algae (Cystoseria indica) to assess heavy metals (Cd, Cu, Zn, Pb, Hg, Ni, Cr) pollution in the northern coasts of the Gulf of Oman

In this study, selected biomarkers-Phytochelatin (PC) and Metallothionein (MT)- were measured in the brown algae (i.e., Cystoseria indica) obtained from the Gulf of Oman. Chemical analyses were performed to measure the concentration of heavy metals (Cd, Cu, Zn, Pb, Hg, Ni, and Cr) in the brown algae. Zn had the highest concentration followed by Cr>Ni>Cu>Pb>Cd>Hg. Performing a spatial analysis revealed that heavy metals had a significant difference (p < 0.05) among sampling sites. Mean PC and MT ranged between 5 and 13 amol/cell and 105-134 µg/g ww, respectively. Significant correlations were found between heavy metal (Cd, Cu, Zn, Pb, Ni, and Cr) concentrations and MT. However, statistically significant correlations were only found between heavy metals (Cd, Zn) and PC (p < 0.01). The results showed that PC reacts to heavy metals less than MT in brown algae (C. indica) which limits the use of PC in heavy metals biomonitoring.

Metals in Blood and Eggs of Green Sea Turtles (Chelonia mydas) from Nesting Colonies of the Northern Coast of the Sea of Oman

The green sea turtle (Chelonia mydas) has been a species of global concern for decades. In this study, heavy metals (mercury: Hg; Cadmium: Cd; Lead: Pb; Copper: Cu; and Zinc: Zn) were measured in blood and three egg fraction of green sea turtles nesting on the northern coast of Sea of Oman. Heavy metals concentrations in blood, yolk, albumen, and egg shell ranged between 0.16-36.78, 0.006-33.88, 0.003-4.02, and 0.002-6.85 μg/g (ww), respectively. According to the results, all heavy metals found in blood samples (n = 12) also were detected in the various parts of the eggs (n = 48). Moreover, there were no significant differences between concentrations of heavy metals in different clutches laid in a nesting season. However, Pb concentrations in blood samples significantly increased in later clutches (p < 0.05), whereas Cu concentrations in blood samples exhibit a declining trend (p < 0.05). These results reveal the existence of maternal transfer phenomenon in green sea turtles on the northern coast of Sea of Oman. Results of this study suggest that heavy metals could be one of the factors influencing reductions in fertilization and hatching success. Results also indicate that green sea turtle on the northern coast of Sea of Oman have high capacity in rapid response and detoxification of heavy metals and/or from the low exposure levels of these turtles to the heavy metals. Further research is required concerning the effects of heavy metals on green sea turtles, especially on their possible influence of fetal development of turtles.

The evaluation of BMI and serum beta-endorphin levels: the study of acute exercise intervention

AIM

The aim of this study was to compare BMI and the effects of a session of acute exercise on serum beta-endorphin levels among the sprint swimmers and runners.

METHODS

In a semi-experimental study, 15 healthy skilled male swimmers (mean and SD of age: 21.64 ± 2.35, weight: 75.25 ± 9.81 kg, height: 180.31 ± 4.75 cm), and 14 healthy skilled runners (age: 21.38 ± 2.76, weight: 69.78 ± 6.86 kg, height: 182.21 ± 5.22 cm), purposefully and voluntarily participated in this study. Venous blood samples of the subjects were taken in three stages 1) basic conditions; 2) immediately after each field of specialized training, with an intensity equal to 80-85% VO(2max) 30 minutes after exercise in the fasting state. Data was analyzed using with repeated measures (ANOVA).

RESULTS

The body composition and anthropometric variables assessed in the study were not significantly different between the 2 groups, except BMI, which was significant (P<0.05). The baseline β-endorphin serum levels were significantly higher in swimmers than runners (P=0.009). There were significant differences between levels of beta-endorphin of male sprint runners and swimmers in the three periods before, immediately after and 30 minutes after exercise (P ≤ 0. 05).

CONCLUSION

The results showed that Increased fat storage may underlie the higher BMI observed in swimmers compared to runners and B-Endorphin Serum Levels was in swimmers more than runners and an acute exercise session significantly increases the levels of beta-endorphin serum hormone in sprint swimmers and runners.

Biochemical and histological changes in fish, spotted scat (Scatophagus argus) exposed to diazinon

Pesticide accumulates in aquatic ecosystems and exerts toxic effects on aquatic animals. In this study, stress parameters and tissue histopathology under acute diazinon exposure were investigated in fish, scat (Scatophagus argus). Spotted scat was exposed to different diazinon concentrations (0, 10, 20, 30 μg L(-1)) for 24, 48, 72, 96 h. Cortisol and glucose levels showed a significant increase after exposure to different diazinon concentration with increase in exposure time. The electrolytes (K(+), Cl(-), Ca(2+), Na(+)) and glucose were differentially affected during the exposure to diazinon. Gill and kidney tissues showed many histopathological changes in diazinon-exposed fish. These results suggest that the release of spotted scat (S. argus) into the diazinon-contaminated regions may alter their physiology and jeopardize their survival.

Polycyclic aromatic hydrocarbons in the coastal sea water, the surface sediment and Mudskipper Boleophthalmus dussumieri from coastal areas of the Persian Gulf: source investigation, composition pattern and spatial distribution

BACKGROUND

Persian Gulf is an exposed and stressed area as a result of oil pollution and other fossil fuels containing PAHs. The susceptibility of using mudskippers to monitor marine pollution, like PAHs, points to the fact that mudskippers are able to accumulate and record the PAHs presented in the coastal environments.

METHODS

Polycyclic aromatic hydrocarbons (PAHs) were examined in the coastal waters, the sediments and biota (i.e., Boleophthalmus dussumieri) along the coast of the Persian Gulf. PAHs concentrations were measured with HPLC method.

RESULTS

Total PAH concentrations in the sea water, the sediments, the liver and the gill tissues ranged between 0.80-18.34 μg/l, 113.50-3384.34 ng g-1 (d w), 3.99-46.64 ng g-1 (d w) and 3.11-17.76 ng g-1 (d w), respectively. PAHs distribution patterns in the sediment and the liver tissue samples were dominated by three-and four-ring structures whereas two-and three-rings were dominated in the water and the gill.

CONCLUSIONS

This finding revealed a negative eco-risk effects occasionally occur in this area. The higher presence of low condensate ring structures reflected a predominant origin of petrogenic and some cases of pyrolitic sources.

Effect of 16 pure hydrocarbons on the stabilization and lysis of fish (mudskipper: Boleophthalmus dussumieri) erythrocytes

The in vitro effects of polycyclic aromatic hydrocarbons (PAHs) on erythrocyte membrane stability of the mudskipper (i.e., Boleophthalmus dussumieri) were tested by using field concentrations, acute and chronic potency divisor concentrations. This was achieved by studying their lytic or antilytic effects on fish erythrocytes in critical hypotonic saline media. The interaction of PAHs acute potency divisor concentrations with mudskipper erythrocyte causes dramatic changes in the structure of the membrane. A significant difference (p<0.05) was found between the control and treatment groups of mudskipper erythrocyte exposed to acute potency divisor concentrations. No significant difference (p>0.05) was observed between the control and the treatment groups of mudskipper erythrocyte exposed to field concentrations. The results showed that chronic potency divisor concentrations of PAHs protect mudskipper erythrocyte against osmotic hemolysis. Our results could be extended to the use of Erythrocyte Osmotic Fragility (EOF) test as a biochemical marker of membrane toxicity in marine pollution biomonitoring. However, results showed that membrane stability is not an appropriate biomarker for PAHs pollution after short exposure duration.

Evaluation of glutathione S-transferase activity as a biomarker of PAH pollution in mudskipper, Boleophthalmus dussumieri, Persian Gulf

As an attempt to study on the biomarkers types to assess the specification of the pollutants and health status of marine ecosystems, sediments and biota (i.e., Boleophthalmus dussumieri) were collected from the Persian Gulf. The liver glutathione S-transferase (GST) activity in mudskipper was higher as compared with that in blood which could be illustrated by high metabolic rate in this organ, its key role in the metabolism of PAHs detoxification and specificity of enzymes composition. The results suggest that the liver GST activity in B. dussumieri was PAH inducible and could be extended as a biomarker of PAH pollution.

Application of biomarkers in mudskipper (Boleophthalmus dussumieri) to assess polycyclic aromatic hydrocarbons (PAHs) pollution in coastal areas of the Persian Gulf

In this study, selected biomarkers-The retention time (RT) performed on haemocytes, the Erythrocyte Osmotic Fragility (EOF) and the Glutathione-S Transferase (GST) activity in the liver- were measured in mudskipper (i.e., Boleophthalmus dussumieri) obtained from the Persian Gulf. Chemical analyses included the assessment of the polycyclic aromatic hydrocarbons (PAHs) in the sediment and mudskipper liver. Total PAH concentrations in the sediment and the liver tissues ranged between 113.50-3384.34 ng g(-1) dw and 3.99-46.64 ng g(-1) dw, respectively. Spatial evaluation indicated that RT had a significant difference (p<0.05) among sampling sites except Arvand and Zangi. The mean erythrocyte fragility was significantly differ between various locations (p<0.05). GST activity in the liver of mudskippers showed significant differences (p<0.05) among Jafari, Bahrakan, and with other sites. No significant difference (p>0.05) was observed between Arvand, Zangi and Samayeli. Additionally, significant correlations were found between total PAHs levels and selected biomarkers (p<0.01). The biomarkers measured in this study were useful as a first investigation into the biological effects of PAHs pollution as well as in determining the bioavailability of pollution.

Evaluation of metallothionein expression as a biomarker of mercury exposure in Scatophagus argus

The effect of mercury exposure to total Metallothionein (MT) response and bioaccumulation under control and acute mercury exposure were investigated in scats (Scatophagus argus). Scats were exposed to different mercury concentrations (10, 20 and 30 microg Hg L(-1)) for 24, 48 and 72 h. Total MT levels were determined by Enzyme-Linked Immunosorbent Assay (ELISA) method. Mercury contents were determined through cold Vapour atomic Absorption spectrometry. Induction of MT during exposure was tissue specific, displaying different response pattern in gill and liver. Mercury accumulated much stronger in liver than gill and the latter also showed lower MT level. MT biosynthesis in liver showed a significant increase after exposure to different mercury concentration during different times. This increase was significantly correlated with mercury bioaccumulation. In contrast, presence of different mercury concentration during different times did not significantly modify total MT except for 72 h exposure at 30 microg L(-1) in gills. The results suggest that this form of MT existing in S. argus was Hg-inducible and could be extended the as a biomarker of mercury pollution in ecosystems.