Iranian Journal of Toxicology
Volume:15 Issue: 2, May 2021

High levels of heavy metals in food are general concerns including carcinogenic effects. According to studies, the accumulation of heavy metals in crops and consumption of these products in diet, has led to serious health concerns. This study investigated the concentrations of lead and cadmium in popular agricultural products.

In this descriptive study, some fresh agricultural products (leafy vegetables, tubers, cucurbits and seeds) were collected in the winter and summer. The samples were transferred to the laboratory and stored in a cold room. After the preparation of the samples, the lead and cadmium contents were determined by atomic absorption spectrometry. The data were analyzed statistically on SPSS v. 26 software.

The average concentrations of lead and cadmium in the winter was 37.23±4.7 and 34.77±0.5 while they were 44.12±0.02 and 56.83±0.01 μg/g in the summer. The highest amount of led content was reported in spinach at an average of 71.25 μg/g and the lowest content was found in watermelon at 30.67 μg/g. We observed a significant rise in the concentrations of the pollutants in leafy vegetables during the summer, which was also linked to the farms’ locations (P<0.05).

The results showed that the highest amount of lead accumulation was found in leafy vegetables and that of the cadmium was at permissible levels in all produces as recommended by WHO. The risk of non-cancerous diseases was also low. Future studied are warranted to assess the risk of heavy metal toxicity in people, especially in children, the elderly and pregnant women.

Trimethyltin (TMT) is a toxic agent that causes oxidative stress, a laboratory model for inducing hippocampal injuries. Pentoxifylline (PTX) inhibits phosphodiesterase, inflammation and oxidative stress. This study evaluated the neuroprotective effects of PTX on injuries induced by TMT in the hippocampus.

Sixty male Wistar rats were divided into five groups of 12 each. Group 1 received normal saline while Group 2 received a single dose of TMT (8 mg/kg). The other four groups received TMT at 8 mg/kg plus 60, 100 or 120 mg/kg PTX twice daily for six consecutive days. The rats’ working and reference memory were investigated, using radial arm maze tasks. At the end of the experiments, the rats’ brains were removed and processed for histological study of the hippocampus.

The TMT treatment prolonged the four baited arms tasks (P<0.001), while the PTX treatment at 60, 100 or 120 mg/kg significantly reduced the effects of TMT on the spatial memory (P<0.01). The working and reference memory errors significantly increased in the TMT group compared to the controls (P<0.001) while the PTX treatment significantly reduced the TMT effect (P<0.001). Also, TMT increased the number of pyknotic cells in the hippocampus (P<0.001), while PTX significantly decreased the mean number of pyknotic cells (P<0.05).

The findings suggest that PTX can protect against the memory deficit and deleterious effects on rat hippocampus induced by TMT neurotoxicity. Thus, PTX is likely to be a potential agent to prevent against the neurotoxicity induced by TMT.

Cisplatin has cytotoxic effects through free radical generation. Reports indicate that various members of Pinaceae family may have antioxidant properties. In this study we investigated the cytoprotective effects of needle volatile oil and bark extract of Pinus eldarica in Hepatoma G2 (HepG2) cell line.

Using the maceration technique, we obtained the ethanolic extract of Pinus eldarica’s bark (BHAEPE). Folin-ciocalteu reagent was used to determine the total phenolic content of BHAEPE. The Needle’s Volatile Oil of Pinus eldarica (NVOPE) was obtained by Clevenger hydrodistillation method. The main components of NVOPE were identified by Gas Chromatography and Mass Spectrophotometry (GC-MS). We used DPPH assay to investigate the antioxidant activity of both NVOPE and BHAEPE. Also, MTT assay was performed to test the protective effects of both BHAEPE and NVOPE against cisplatin.

Folin-ciocalteu test demonstrated that each gram of BHAEPE was equivalent to 371±6 mg of gallic acid. Also, GC-MS identified germacrene D as the main component of NVOPE. BHAEPE had more antioxidant capacity compared to NVOPE. When incubated solely with cells, neither BHAEPE nor NVOPE represented cytotoxicity on. Furthermore, BHAEPE demonstrated mitogenic effects on higher doses (50, 75 and 100 μg/ml). However, both NVOPE and lower doses of BHAEPE (10, 20 μg/ml) could not protect the cells against cisplatin’s cytotoxicity, but higher doses of BHAEPE provided cytoprotective effects.

The antioxidant properties of both NVOPE and lower doses of BHAEPE did not adequately protect HepG2 cells against the cisplatin’s cytotoxicity. However, BHAEPE at high concentrations demonstrated cytoprotective effects.

The toxic effect of sodium arsenate on nervous system has been shown; but the protective effects of several compounds against sodium arsenate are not clear. This study aimed to investigate the protective effects of nicotine and bucladesine, two positive modulators of neuronal function, on sodium arsenate toxicity against avoidance memory impairment.

Male mice (N=154) were assigned to 22 groups (12 experimental and 10 control) of seven animals each and were treated as follows: sodium arsenate (2.5, 5, or 10 mg/kg) for 28 days, nicotine (1 mg/kg) for either 1, 2, or 4 days, bucladesine (600 nM/mouse) for either 1, 2, or 4 days, and nicotine (1 mg/kg)+bucladesine (600 nM/mouse)+sodium arsenate (2.5 mg/kg). The last group was treated with 2.5 mg/kg sodium arsenate first, and then received the combination of nicotine and bucladesine for 1, 2, or 4-days. The corresponding control groups did not receive any drug but either saline, deionized water, or combination of deionized water and DMSO, but went through the same procedure as other animals. All mice were trained 24 h in the step-through passive avoidance task. The avoidance memory retention was assessed at 24, 48, 96, and 168 h after the training period by measuring the time they stayed in a dark chamber.

All sodium arsenate doses significantly reduced the time stayed in the dark chamber regardless of the treatment duration (24, 48, 96 & 168 h) after training. Both nicotine and bucladesine, whether used singly or combined for 1, 2, and 4 days significantly enhanced the time latency compared to the controls at all of the experimental timepoints following the training.

Nicotine and bucladesine showed synergistic effects and reversed the sodium arsenate-induced avoidance memory deficits in mice.

According to Hindu mythology, Yamuna River plays an impotent role as a holy water resource in Delhi, India. The lead and chromium concentrations were determined from the water samples collected from five different locations around this river in Delhi area. The contaminated water from this river is mostly used for drinking, agriculture, aquaculture, and storage as a holy water.

The seasonal variations of heavy metal concentrations in the water samples collected from Yamuna river were determined for the summer, monsoon and winter supplies, using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Atomic Absorption Spectroscopy (AAS).

In the summer water samples, we found greater concentrations of both heavy metals than those for the monsoon season. The concentrations of lead and chromium in the water samples were higher than the permissible limits recommended by the World Health Organization (WHO). The water quality was not safe for drinking, cleaning and agriculture, nor for the aquatic animals, such as fish, amphibians and others.

The condition of the water in Yamuna river is of great health concerns. Therefore, it is vital to take necessary actions to decontaminate the water from this river, and to draw effective strategies to minimize or prevent the current and future contaminations added to this important water resource in India.

Endocrine compounds, such as Bisphenol A (BPA), stimulate or inhibit the activities of hormones, nuclear receptors in the central nervous system, liver and other organs. They may be disposed of in the environment inadverdently around industrial sites. The aim of this study was to evaluate the cytotoxic effects of BPA on human lymphocytes in culture at varying concentrations.

0.1 mL heparinized 0.2 mL peripheral blood taken from a healthy male and a female were plated in culture media under sterile conditions. To prepare the reference dose at a concentration of 0.05 mg/mL, 0.027g BPA was dissolved in 1 L dimethyl sulfoxide and the highest dose of 50 μg/mL BPA solution was prepared. After separating the stock solution, 50 μg/mL BPA was diluted to prepare 20, 10 or 5 μg/mL doses.

After 24 h of incubation, abnormal cell±Standart Error (%)[AC±SE (%)] 1.10±1.0, chromosomal aberration/cell±Standart Error (CA/cell±SE) 0.025±0.01 was determined in control group, and AC±SE (%) 2.00±0.98 in control group. After 48 h of incubation 0.98, CA/ cell±SE was found to be 0.020±0.01. After 24 and 48 h of incubation, AC±SE (%) and CA/ cell±SE ratios were 30.00±3.24, 34.00±3.35 and 0.325±0.03, 0.430±0.04, respectively.

The cytotoxic effect of BPA on human lymphocytes was investigated in this study at reference concentration and lower doses. Our findings support the fact that BPA substitutes may not be sufficiently safe for widespread use as industrial chemicals.

One of the concerns of consumers of animal protein sources is the residues of heavy metals in meat. The accumulation of these elements in meat and the consumption by humans can cause acute and chronic disorders in the function of vital organs.

For the estimation of cadmium, zinc and silver in the poultry meat products, 100 samples of chicken breasts, thighs, hearts and livers were collected from meat markets in Isfahan Province. The tissues were digested and passed through filter paper, and the cadmium, zinc and silver contents were measured by an atomic absorption spectrophotometer.

The mean contents of cadmium in the chicken thigh, breast, liver and heart samples were 0.055±0.021, 0.048±0.023, 0.074±0.031, and 0.012±0.004 mg/kg, respectively. The mean contents of zinc in the chicken thigh, breast, liver and heart samples were 17.19±8.10, 15.70±5.75, 22.10±10.87, and 19.70±10.38 mg/kg, respectively. The concentrations of cadmium and zinc were below the international permissible limits in all samples. The mean concentrations of silver in some chicken thigh, breast, liver and heart samples were 0.0080±0.0044, 0.0048±0.0013, 0.012±0.009 and 0.0036±0.006, respectively. Of note, silver was not detected in most chicken samples.

This study did not find cadmium, zinc and silver in the chicken meat samples above the international permissible limits. However, frequent monitoring for heavy metals in poultry meat sold in public markets is warranted to prevent their transmission to the human food chain.

Among aflatoxins, the subtype aflatoxin G1 is one of the most toxic, commonly found in cereals, legumes, dairy and non-alcoholic beers. Aflatoxins have been known as nephrotoxic compounds. In this study, changes in the expression of aquaporin-1, the histopathology of renal tissue and plasma biochemical factors after exposure to aflatoxin G1 were investigated in mice.

Twenty-four adult male mice (weighing 20±2 g) were divided into four groups of six. The control group received the vehicle (0.2 ml) and the three experimental groups were injected intraperitoneally with aflatoxin G1 at 20 μg/kg for 7, 15 or 35 days, respectively. On days 7, 15 and 35, blood samples were drawn from the mice for biochemical analysis of plasma and the kidney tissues were sampled for real-time PCR and histopathological studies.

The real PCR results showed a reduction in aquaporin-1 expression in the experimental groups compared to those in the controls (P<0.05). Also, the plasma concentrations of urea and creatinine were significantly increased in the experimental groups compared to those in the controls (P<0.05). Also, the serum sodium and potassium levels had decreased significantly compared to the controls (P<0.05). Various damages were observed in the ureters and glomeruli among the experimental groups compared to those in the controls.

Aflatoxin G1 had adverse effects on the renal tissue by reducing the expression of aquaporin-1. Subsequently, there were biochemical manifestations in the serum, consisting of changes in the concentrations of urea, creatinine, sodium and potassium, confirming the histopathological toxicity of aflatoxin G1.