Emission-related Heavy Metal Associated with Oxidative Stress in Children: Effect of Antioxidant Intake

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.

Aquatic assessment of the chelating ability of Silica-stabilized magnetite nanocomposite to lead nitrate toxicity with emphasis to their impact on hepatorenal, oxidative stress, genotoxicity, histopathological, and bioaccumulation parameters in Oreochromis niloticus and Clarias gariepinus

BACKGROUND

In recent years, anthropogenic activities have released heavy metals and polluted the aquatic environment. This study investigated the ability of the silica-stabilized magnetite (Si-M) nanocomposite materials to dispose of lead nitrate (Pb(NO3)2) toxicity in Nile tilapia and African catfish.

RESULTS

Preliminary toxicity tests were conducted and determined the median lethal concentration (LC50) of lead nitrate (Pb(NO3)2) to Nile tilapia and African catfish to be 5 mg/l. The sublethal concentration, equivalent to 1/20 of the 96-hour LC50 Pb(NO3)2, was selected for our experiment. Fish of each species were divided into four duplicated groups. The first group served as the control negative group, while the second group (Pb group) was exposed to 0.25 mg/l Pb(NO3)2 (1/20 of the 96-hour LC50). The third group (Si-MNPs) was exposed to silica-stabilized magnetite nanoparticles at a concentration of 1 mg/l, and the fourth group (Pb + Si-MNPs) was exposed simultaneously to Pb(NO3)2 and Si-MNPs at the same concentrations as the second and third groups. Throughout the experimental period, no mortalities or abnormal clinical observations were recorded in any of the treated groups, except for melanosis and abnormal nervous behavior observed in some fish in the Pb group. After three weeks of sublethal exposure, we analyzed hepatorenal indices, oxidative stress parameters, and genotoxicity. Values of alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), urea, and creatinine were significantly higher in the Pb-intoxicated groups compared to the control and Pb + Si-MNPs groups in both fish species. Oxidative stress parameters showed a significant decrease in reduced glutathione (GSH) concentration, along with a significant increase in malondialdehyde (MDA) and protein carbonyl content (PCC) concentrations, as well as DNA fragmentation percentage in the Pb group. However, these values were nearly restored to control levels in the Pb + Si-MNPs groups. High lead accumulation was observed in the liver and gills of the Pb group, with the least accumulation in the muscles of tilapia and catfish in the Pb + Si-MNPs group. Histopathological analysis of tissue samples from Pb-exposed groups of tilapia and catfish revealed brain vacuolation, gill fusion, hyperplasia, and marked hepatocellular and renal necrosis, contrasting with Pb + Si-MNP group, which appeared to have an apparently normal tissue structure.

CONCLUSIONS

Our results demonstrate that Si-MNPs are safe and effective aqueous additives in reducing the toxic effects of Pb (NO3)2 on fish tissue through the lead-chelating ability of Si-MNPs in water before being absorbed by fish.

The effects of active and passive smoking on selected trace element levels in human milk

Our study aimed to compare levels of six micro-elements and six potentially toxic elements in the breast milk of non-smoking women compared to those found in women who smoke tobacco and women exposed to second-hand smoke during pregnancy and lactation. This was a cross-sectional study conducted on 100 lactating women in western Iran. The studied subjects were in three groups: passive smokers, active smokers, and a control group. Concentrations of selected trace elements in breast milk (essential and non-essential metals) were determined using ICP-MS. Our results indicated that the parameters of education, fruit consumption, and cosmetics usage had a significant difference among the groups (p < 0.05). Moreover, for trace elements, the Kruskal-Wallis test was statistically significant for arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) (p < 0.05). The post hoc Dunn test revealed a significant difference in the levels of As, Cd, Hg, and Pb between non-smoker and passive/active smoker groups (p < 0.05). Our findings illustrate that exposure to cigarette smoke can cause an increase in the level of potentially toxic elements in human milk, which is dangerous for the consumption of premature newborns, but more research is needed to evaluate the potential toxic mechanisms of toxic metals.

"Assessing exposure of printing factory workers in thailand to selected heavy metals using urine and hair as non-invasive matrices"

BACKGROUND

There are few thorough studies on the extent and inter-element relationships of heavy metal contamination in printing factory workers, especially in developing countries. The objective of this study was to determine the levels of eight heavy metals, including arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni), cobalt (Co), lead (Pb), mercury (Hg), and manganese (Mn), in urine and scalp hair of printing industry workers, and assess inter-element correlations.

METHODS

We examined a total of 85 urine samples and 85 scalp hair samples (3 cm hair segments taken from near the scalp) in 85 printing workers from a printing house in Bangkok, Thailand. We used an interviewer-administered questionnaire about participants' printing techniques, work characteristics, and work environment. Urine and scalp hair samples were analyzed for levels of each element using the inductively coupled plasma optical emission spectrometry (ICP-OES) technique.

RESULTS

As, Cd, Cr, Ni, Pb were detected in urine with the geometric mean concentration range of 0.0028-0.0209 mg/L, and Hg, Pb, Ni, Cd, Co, Mn, Cr were detected in hair samples (0.4453-7.165 mg/kg dry weight) of printing workers. The geometric mean Ni level was significantly higher in the urine of production line workers than back-office personnel (0.0218 mg/L vs. 0.0132 mg/L; p = 0.0124). The other elements did not differ significantly between production line and back-office workers in either urine or hair. There was also a strong, statistically significant positive correlation between Ni and Co levels in hair samples of workers (r = 0.944, p < 0.0001).

CONCLUSIONS

Average concentrations of most of the metals in urine and hair of printing workers were found to be above the upper reference values. The significantly higher concentrations of Ni in production line workers might be due to more exposure to printed materials. A strong inter-element correlation between Ni and Co in hair samples can increase stronger health effects and should be further investigated. This study reveals possible dependencies and impact interactions of heavy metal exposure in printing factory workers.

Genotoxic Biomonitoring in Children Living near the El Fraile Mine Tailings in Northern Guerrero State, Mexico

A genotoxic study was conducted with 101 elementary school children (56 girls and 45 boys) in the 6-7, 8-9, and 10-12 age ranges from El Fraile rural community, which is located beside the El Fraile mine tailings in Taxco of Alarcon City, in northern Guerrero State, Mexico. For this, we used the alkaline comet assay in exfoliated buccal mucosa cells, scoring three genotoxic parameters: tail intensity, tail moment, and tail length. Additionally, we detected oxidative DNA damage through urinary 8-OHdG levels by enzyme-linked immunosorbent assay. We also evaluated a control group consisting of 101 children in the same age ranges from Chilpancingo City, Guerrero, who had never lived near mining zones. Genotoxic results showed that there was a significant increase in three genotoxic parameters and urinary 8-OHdG levels in the exposed children group compared with the control group. Analysis of MANOVA revealed that boys aged 8 and 9 years had higher DNA damage than girls from the same exposure group, and Spearman's analysis identified a positive correlation between DNA damage and sex and age. This study provides the first valuable genotoxic data in children living in areas with environmental pollution.

Associations of multiple metals with lung function in welders by four statistical models

BACKGROUND

Exposure to heavy metals has been related to decreased lung function in workers. However, due to limitations in statistical methods for mixtures, previous studies mainly focused on single or several toxic metals, with few studies involving metal exposome and lung function.

OBJECTIVES

The study aimed to evaluate the effects of co-exposure to the metal mixtures on multiple parameters of pulmonary function tests and to identify the elements that play an essential role in elastic-net regression (ENET), multivariate linear regression, bayesian kernel machine regression (BKMR), and quantile g-computation (QG-C) models.

METHODS

We have recruited 186 welders from Anhui (China) in 2019. And their end-of-shift urine and lung function measure data were collected with informed consent. The urinary concentrations of 23 metals were measured by inductively coupled urinary mass spectrometry. The lung function measures including forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1) and peak expiratory flow (PEF) were also detected as outcome indicators. Four statistical methods, ENET, multivariate linear regression, BKMR, and QG-C models were used to evaluate the associations of element mixtures on lung function comprehensively.

RESULTS

Lead and cadmium were negatively associated with FVC and FEV1, nickel and chromium were inversely associated with PEF, and strontium showed significant positive effects in linear regression models, which were consistent with the results in BKMR and QG-C models. Both BKMR and QG-C models showed a significantly negative overall effect of metal mixtures on lung function parameters (FVC, FEV1, and PEF). Meanwhile, BKMR showed the non-linear relationships of cadmium with FVC.

CONCLUSION

Multi-pollutant mixtures of metals were negatively associated with lung function. Lead, cadmium, nickel, and strontium might be crucial elements. Our findings highlight a need to prioritize workers' environmental health, and guide future research into the toxic mechanisms of metal-mediated lung function injury.

Metabolomic Approach for Rapid Identification of Antioxidants in Clinacanthus nutans Leaves with Liver Protective Potential

Antioxidants are currently utilized to prevent the occurrence of liver cancer in non-alcoholic fatty liver disease (NAFLD) patients. Clinacanthus nutans possesses anti-oxidative and anti-inflammatory properties that could be an ideal therapy for liver problems. The objective of this study is to determine the potential antioxidative compounds from the C. nutans leaves (CNL) and stems (CNS). Chemical- and cell-based antioxidative assays were utilized to evaluate the bioactivities of CNS and CNL. The NMR metabolomics approach assisted in the identification of contributing phytocompounds. Based on DPPH and ABTS radical scavenging activities, CNL demonstrated stronger radical scavenging potential as compared to CNS. The leaf extract also recorded slightly higher reducing power properties. A HepG2 cell model system was used to investigate the ROS reduction potential of these extracts. It was shown that cells treated with CNL and CNS reduced innate ROS levels as compared to untreated controls. Interestingly, cells pre-treated with both extracts were also able to decrease ROS levels in cells induced with oxidative stress. CNL was again the better antioxidant. According to multivariate data analysis of the 1H NMR results, the main metabolites postulated to contribute to the antioxidant and hepatoprotective abilities of leaves were clinacoside B, clinacoside C and isoschaftoside, which warrants further investigation.

Genotoxic effect of microplastics and COVID-19: The hidden threat

Microplastics (MPs) are ubiquitous anthropogenic contaminants, and their abundance in the entire ecosystem raises the question of how far is the impact of these MPs on the biota, humans, and the environment. Recent research has overemphasized the occurrence, characterization, and direct toxicity of MPs; however, determining and understanding their genotoxic effect is still limited. Thus, the present review addresses the genotoxic potential of these emerging contaminants in aquatic organisms and in human peripheral lymphocytes and identified the research gaps in this area. Several genotoxic endpoints were implicated, including the frequency of micronuclei (MN), nucleoplasmic bridge (NPB), nuclear buds (NBUD), DNA strand breaks, and the percentage of DNA in the tail (%Tail DNA). In addition, the mechanism of MPs-induced genotoxicity seems to be closely associated with reactive oxygen species (ROS) production, inflammatory responses, and DNA repair interference. However, the gathered information urges the need for more studies that present environmentally relevant conditions. Taken into consideration, the lifestyle changes within the COVID-19 pandemic, we discussed the impact of the pandemic on enhancing the genotoxic potential of MPs whether through increasing human exposure to MPs via inappropriate disposal and overconsumption of plastic-based products or by disrupting the defense system owing to unhealthy food and sleep deprivation as well as stress. Overall, this review provided a reference for the genotoxic effect of MPs, their mechanism of action, as well as the contribution of COVID-19 to increase the genotoxic risk of MPs.

Toxic metals in human milk in relation to tobacco smoke exposure

Several reports confirm the deleterious effects of tobacco smoking and exposure to second-hand smoke (SHS) resulting in changes in the composition of breast milk. The aim of our study was to compare the levels of selected essential, as well as, toxic metals found in colostrum (collected at day 1 ± 2 post-birth) and mature milk (1 month ± 7 days post-birth) of nonsmoking women (n = 52) compared to those found in women who smoke tobacco (n = 51) and women exposed to second-hand smoke during pregnancy and lactation (n = 47). Women's non-smoking or smoking status was determined by their responses to a questionnaire, including questions about others who may smoke in the home environment, and confirmed by measurement of cotinine in the blood serum by high performance liquid chromatography with diode array detector (HPLC-DAD). Inductively coupled plasma mass spectrometry (ICP-MS) and flame atomic absorption spectroscopy (F-AAS) techniques were used to determine the metal concentrations in colostrum and mature milk previously digested by a microwave mineralizer. We confirmed that exposure to tobacco smoke increases concentrations of heavy metals (cadmium and lead) in colostrum and mature milk. These increased concentrations of heavy metals may disturb the action of bioactive substances necessary for the optimal growth and development of newborns and infants. These findings support the need for increased concern and information to lactating women about preventing their exposure to cigarette smoking and SHS due to the adverse effects of tobacco smoke on breast milk with added risks to their infants.