Assessment of Some Heavy Metals and Their Relationship with Oxidative Stress and Immunological Parameters in Aquatic Animal Species

Metagenomic insights into the alterations of gut microbial community in Bufo gargarizans tadpoles following lead exposure

Lead (Pb), a prevalent heavy metal contaminant in aquatic environments, has complex effects on the gut microbiome function of aquatic animals. In this study, metagenomic analysis of Bufo gargarizans tadpoles was carried out following Pb exposure. Moreover, histological analysis was performed on the intestines. The results showed that Pb exposure induced histological damage to the intestinal epithelium. Significant differences in microbial abundance and function were detected in the 200 μg/L Pb group compared to the control group. Specifically, an increase in Bosea and Klebsiella was noted at 200 μg/L Pb, which potentially could induce inflammation in tadpoles. Notably, the decrease in the abundance of glycoside hydrolases subsequent to exposure to 200 μg/L Pb is likely to attenuate carbohydrate metabolism. Furthermore, increased fluoroquinolone-related antibiotic resistance genes (ARGs), phenolic-related ARGs, and iron uptake systems following 200 μg/L Pb exposure might heighten the disease risk for tadpoles. These discoveries augment our comprehension of the influences of Pb on the intestinal well-being of amphibians and offer valuable insights for further assessment of the ecological risks that Pb poses to amphibians.

Comparative Evaluation of Levamisole and Broccoli in Mitigating Testicular Oxidative Stress and Apoptotic Alterations Caused by Cadmium and Lead Exposure in Rats

Considering the significance of heavy metals in infertility and their reduction through natural and synthetic compounds, a comparative study of broccoli and levamisole in cadmium and lead poisoning was conducted. Male Wistar rats (48 in total) were divided into 8 groups. Control, cadmium, lead, levamisole, and broccoli were administered individually to groups 1-5, while groups 6-8 received combinations. Various measurements were taken, including final weight, testicular weight, and the GSI coefficient. Sperm parameters, spermatogenesis cell count, oxidative stress biomarkers, and apoptosis indices were assessed using ELISA kits and methods in testicular tissue. The results indicated that the GSI coefficient was lowest in group 2 and highest in group 4, showing a significant difference (P < 0.001). Sperm concentration peaked in group 1 and broccoli-treated ones, while motility was highest in group 5. Testicular cell counts and Johnson score were highest in groups 1 and 2, and lowest in cadmium-exposed groups. These differences were statistically significant at P < 0.01. Enzyme activities related to oxidative stress varied. Group 2 exhibited the highest catalase (CAT) and superoxide dismutase (SOD) activities, while glutathione peroxidase (GPx) levels peaked in groups 1, 4, and 5. Malondialdehyde (MDA) concentrations were significantly reduced in the group 5 (P < 0.05). Apoptosis indices revealed that broccoli had the highest Bcl-2 levels and lowest Bax/Bcl-2 ratio, indicating its anti-apoptotic effect. Group 4 showed less efficacy compared to broccoli in protecting fertility indices. In conclusion, cadmium and lead significantly impact male fertility, while broccoli extract demonstrates promising efficacy in mitigating damage when compared to levamisole. This underscores its antioxidant and anti-apoptotic properties.

Effects of Brown Algae (Laminaria japonica) Extract on Growth Performance, Immune Function and Intestinal Health of Largemouth Bass (Micropterus salmoides)

This study used largemouth bass (initial average weight: 33.33 ± 1.8 g) to explore the effects of adding different brown algae extracts to feed on the fish's growth, immunity and intestinal health. Six groups were set up: a control (Group A), 0.1% sodium alginate (Group B), 0.1% oligotriosaccharide I (Group C), 0.1% oligotriosaccharide II (Group D), 0.2% brown algae powder (Group E) and 0.2% brown algae powder enzymatic product (Group F), with three replicates of 35 fish each, and a 56-day feeding experiment. Results: Compared to Group A, Groups C, D and F had a higher specific growth rate and lower feed coefficient (p < 0.05). Group D had enhanced serum SOD activity; Group F had increased antioxidant enzyme activity and decreased MDA content (p < 0.05). All experimental groups had higher serum LZM levels (p < 0.05), with no IgM difference (p > 0.05). In the intestine, treatment groups had higher α-amylase activity (p < 0.05) and no lipase difference (p > 0.05), and Groups C, D and F had higher trypsin activity (p < 0.05). Group F had the tallest villi, Group B had the thickest muscular layer (p < 0.05), and villus width was similar among groups (p > 0.05). The experimental groups had fewer intestinal pathogenic bacteria, and Group F had improved intestinal microorganism diversity and richness (p < 0.05). In conclusion, adding 0.1% oligotriosaccharide and 0.2% brown algae powder enzymatic product to feed can promote largemouth bass growth, antioxidant capacity and immunity. The 0.2% brown algae powder enzymatic product is better for intestinal development and flora improvement.

Assessment of some heavy metals concentration in turkey meat in Kurdistan province and their relationship with oxidative stress and human health indicators

The accumulation of heavy metals is closely related to biochemical parameters and the overall health of both animals and humans. Given the high nutritional value of turkey meat, this study aimed to assess the concentrations of toxic and non-toxic heavy metals in the breast, thigh, and liver tissues of turkeys and examine their relationship with oxidative stress biomarkers. In this cross-sectional study, 150 samples of turkey breast, thigh, and liver from Kurdistan province were collected using a cluster random sampling method. The concentrations of toxic and non-toxic heavy metals were measured using ICP-MS. The correlation between oxidative stress parameters and metal concentrations was investigated. Additionally, the target hazard quotient (THQ) and total risk (TR) for toxic heavy metals were calculated as health indicators. The results indicated that toxic heavy metals, including arsenic, cadmium, and mercury, had significantly higher accumulation in the liver compared to other turkey tissues (P < 0.05). Non-toxic metals, except for magnesium, also demonstrated higher levels in the liver (P < 0.01). The lowest antioxidant enzyme activities of SOD and GPx were observed in the liver, while the highest activities were found in the breast. However, the MDA concentration in the liver (8.96 ± 1.67) was significantly higher than in other tissues (P = 0.016). There was a significant negative correlation between the concentrations of arsenic, cadmium, and mercury and the activities of SOD and GPx enzymes. Conversely, the correlation between MDA and non-toxic metals, including selenium, zinc, and magnesium, was negative (P < 0.05). The accumulation of metals such as arsenic, mercury, copper, and cobalt exceeded permissible levels. The THQ for toxic metals was acceptable; however, the TR for arsenic in the breast, thigh, and liver tissues was within the carcinogenic range. Therefore, reducing and controlling the sources of arsenic as a toxic metal with oxidative effects in turkeys in Kurdistan province requires stringent monitoring and management.

Heavy metal impacts on antioxidants in cow blood from wastewater-irrigated areas

The aim of the present research was to investigate the presence of heavy metals such as lead (Pb), copper (Cu), chromium (Cr), and cadmium (Cd) in blood samples from cows raised with irrigated wastewater, as well as in the wastewater itself, in the North-western region of Pakistan. A total of 60 blood samples were collected from five different locations in Kohat, namely Tappi Road (TR), Pindi Road (PR), Gul Malik Road (GMR), Markaz Road (MR), and a control group. The samples of both i.e. cow blood and wastewater were analyzed for the concentrations of heavy metals. The highest concentration of Cd was detected in the MR site with a mean value of 0.03 mg/L, and the highest concentration of Cu (0.04 mg/L) was recorded in the TR site, while the lowest level was found in the control group with a mean of 0.002 mg/L in blood samples. The highest Cr and Pb concentrations were found at the PR site, with mean values of 0.03 and 0.07 mg/L, respectively, whereas the control group had the lowest concentrations, with mean values of 0.002 and 0.01 mg/L. Similarly, heavy metal concentrations were analyzed in wastewater used for irrigation in the study area. Results indicated elevated concentrations of Cu and Cr in wastewater, although they remained below the World Health Organization (WHO) recommended values except for Cr (0.13 mg/L) in the GMR site, which exceeded permissible limits. Cd and Pb concentrations in wastewater were relatively low, but Cd concentration surpassed WHO limits, particularly with a mean concentration of 0.08 mg/L in the TR site. Comparison between heavy metal concentrations in blood and wastewater revealed higher values of Cd and Pb in blood samples than in wastewater, while Cu and Cr concentrations were higher in water compared to blood. Additionally, elevated levels of Super Oxide Dismutase (SOD), antioxidant enzyme Catalase (CAT), and oxidative stress marker malondialdehyde (MDA) were detected in blood samples. Cluster and principal component analyses were employed to assess heavy metal toxicity among the groups, indicating potential long-term adverse health effects on animals, transfer to humans, and toxicity in living organisms.

Stevioside mitigates lead toxicity in thinlip mullet juveniles: Impacts on growth, metabolism, and immune function

This study investigates the impact of varying concentrations of stevioside in the presence of lead (Pb) exposure on multiple aspects of thinlip mullet (Liza ramada) juveniles. Over 60 days, a total of 540 juvenile L. ramada with an initial weight of 3.5 ± 0.13 g were evenly distributed into six groups, each consisting of three replicates. The experimental diet consisted of varying levels of stevioside (150, 250, 350, and 450 mg/kg diet), with a consistent concentration of lead (Pb) set at 100 µg/kg diet. Stevioside demonstrated a positive influence on growth parameters, with the 450 mg/kg +Pb treatment showing the highest values. Biochemical parameters remained stable, but lead-exposed fish without stevioside displayed signs of potential liver damage and metabolic issues. Stevioside supplementation, especially at higher doses (≥250 mg/kg), reversed these negative effects, restoring biochemical markers to healthy control levels. Lead exposure significantly suppressed antioxidant enzyme activities, but co-administration of stevioside exhibited a dose-dependent protective effect, with 250, 350, and 450 mg/kg groups showing activities comparable to the healthy control. Lead-exposed fish without stevioside demonstrated attenuation of the immune response, but stevioside supplementation reversed these effects, particularly at ≥250 mg/kg. Stev (≥250 mg/kg) reduced IL-1β and hepcidin expression, contrasting dose-dependent upregulation in lower dosages and lead-only group. Histological examinations of the intestine and liver supported these findings. In conclusion, stevioside, especially at 450 mg, positively impacted growth, biochemical parameters, antioxidant activity, immune response, and gene expression in L. ramada exposed to lead, suggesting its potential to mitigate lead toxicity in aquaculture. Additional research is warranted to investigate the long-term impacts of stevioside supplementation and its prospective implementation in aquaculture.

Accumulation of heavy metals in meat and their relationship with water and food intake of aquatic animals in Kermanshah, western Iran

Accumulation of heavy metals in aquatic meat can have a destructive role in food safety and is also closely related to the water and feed consumed by animals. Thus, the aim of this study is to evaluate the heavy metals in three aquatic species and their relationship with water and food. Fresh samples included 65 trout, 40 carp, and 45 shrimp, and their water and food were collected from Kermanshah aquaculture. After the preparation phase, the concentration of heavy metals was determined by using inductively-coupled plasma-mass-spectrometry. Lead in carp, arsenic in shrimp, cadmium, and mercury in trout had the highest concentrations of toxic metals. The lead, arsenic, and mercury concentrations in all three farmed aquatic species were higher than the maximum permissible limits. A significant correlation coefficient was observed between the concentration of these metals in the meat and their consumed water and food (p≤0.001). Of the essential metals, except for selenium in trout, and zinc in all three aquatic species, the concentration of other metals was higher than that of the permissible consumption limit. There was also a significant correlation between the concentration of essential metals and their consumed feed (p<0.001). The target hazard quotient of toxic metals was less than 1, but the target cancer risk for arsenic and mercury was in the range of carcinogenicity. Thereby, it is vital to monitor the quality of aquatic meat and pay special attention to their water and feed sources in this region of Iran, which will consequently guarantee human health.

The Impact of Metal and Heavy Metal Concentrations on Vancomycin Resistance in Staphylococcus aureus within Milk Produced by Cattle Farms and the Health Risk Assessment in Kurdistan Province, Iran

In today's food landscape, the paramount focus is on ensuring food safety and hygiene. Recognizing the pivotal role of the environment and its management in safeguarding animal products, this study explores vancomycin resistance in raw milk from livestock farms in the Kurdistan province and its correlation with metal and heavy metal. One hundred and sixty raw milk samples were collected from various locations, with heavy metal concentrations analyzed using ICP-MS. Identification of Staphylococcus aureus and vancomycin resistance testing were conducted through culture and the Kirby-Bauer method. This study investigates the relationship between resistance and heavy metal levels, revealing that 8.75% of milk samples contained Staphylococcus aureus, with 28.58% exhibiting vancomycin resistance. Significant variations in arsenic, iron, zinc, sodium, and aluminum concentrations were observed between resistant and sensitive samples (p < 0.01). The increase in arsenic, iron, and aluminum, along with the decrease in zinc, demonstrated a significant association with vancomycin resistance (p < 0.001). Levels of lead, cadmium, mercury, zinc, and iron exceeded permissible limits (p < 0.05). The Target Hazard Quotient (THQ) for cadmium indicated a high non-carcinogenic risk, while the Target Risk (TR) for arsenic fell within the carcinogenic range. Accumulation of heavy metals has the potential to impact antibiotic resistance in milk, underscoring the imperative to control arsenic residues for national safety.

The Concentration and Risk Assessment of Potentially Toxic Elements (PTEs) in Farmed and Wild Carps (Cyprinus carpio) in Hamadan Province of Iran

This study focuses on measuring potentially toxic elements (PTEs) including mercury (Hg), lead (Pb), cadmium (Cd), arsenic (As), iron (Fe), copper (Cu), zinc (Zn), manganese (Mn) in farmed and wild carp by inductively coupled plasma-optical emission spectrometry (ICP-OES) and their intake amount and risk assessment. Estimated Daily Intake (EDI), Target Hazard Quotient (THQ) and the total THQ (TTHQ) were calculated for each element. In the present research, the concentration of As in farmed and wild carp samples was below the detection limit of ICP-OES (< 0.005 mg/kg). The mean concentrations of Pb, Cd, Fe, and Cu in farmed carp samples were significantly higher than that in wild carp samples, while Zn level was higher in the wild carp samples (P < 0.05). There is no significant difference between Hg and Mn in both fish (P > 0.05). The Monte Carlo simulation (MCS) results showed that the ranking order of PTEs based on their THQ was Hg > Pb > Zn > Cu > Fe > Cd > Mn. In the worst-case scenario (in the top 95 percentile) for both wild and farmed carp, the THQ of measured metals was less than one except Hg in children. Overall, this study demonstrated that the levels of PTEs in farmed and wild common carp had a potential non-carcinogenic risk for children (TTHQ > 1).