Blood lead concentrations in children with iron deficiency anemia: a systematic review and meta-analysis.

Iron deficiency is the most common nutritional disorder detrimental to the behavior, cognitive performance, immune system, and physical growth of infants and preschool- and school-age children. Iron deficiency anemia (IDA) increases children's susceptibility to some metals, including the highly toxic lead (Pb), but the character of this relationship is still disputed. Thus, this study aimed to review and meta-analyze the association between the IDA and blood lead levels (BLL) among children, based on papers indexed by international scientific databases and published up to September 2021. A search was performed of the literature in several databases including the ISI Web of Science, PubMed, and Scopus. The final papers were assessed concerning their quality based on the Newcastle-Ottawa Scale (NOS) for cross-sectional studies. Moreover, analyses were performed using R statistical software with the "meta" package. Of the 1528 articles found, only 12 studies met the inclusion criteria and were considered in the meta-analysis. Significantly higher BLL in IDA children (SMD = 2.40; CI 95%, 0.93-3.87 µg/L; p = 0.0014) was seen when compared to non-IDA children. Moreover, the pooled OR is equal to 2.75 (CI 95%, 1.10-6.85 µg/L; p = 0.0303) suggesting a higher risk of IDA development among children with BLL > 10 µg/dL. Thus, we recommend systematic monitoring of Fe and Pb levels among children, especially in countries with limited sources of nutritious food. Since only a few studies were available for this meta-analysis, further studies are necessary to examine the association between IDA and BLL in detail.

Relationship between gestational diabetes and serum trace element levels in pregnant women from Eastern Iran: a multivariate approach.

The prevalence of gestational diabetes mellitus (GDM) has increased over the recent decades. Exposure to environmental contaminants may be a risk factor for the development of GDM, but this is heavily dependent on particular circumstances. Studies on various areas linking various factors are therefore needed. We examined the associations between serum trace element levels and incidents of GDM among 102 pregnant women (diabetic n = 60 and healthy n = 42) living in Birjand (Iran). Blood serum samples were analyzed for concentrations of elements linked to particulate matter air pollution such as As, Cd, Cu, Hg, Mn, Ni, V, and Zn. Concentrations of As (8.58 vs. 3.15 µg/L), Cd (6.74 vs. 0.52 µg/L), and Hg (2.60 vs. 0.90 µg/L) were significantly higher in women with GDM. Risk difference (RD) estimation showed that As, 0.516 (0.355, 0.677); Cd, 0.719 (0.534, 0.904); and Hg, 0.505 (0.276, 0.735) increase GDM probability, while V lower that risk, -0.139 (-0.237, -0.042). With the principal component analysis, we were able to separate subjects according to their GDM status based on element levels. Such classification revealed very high efficiency with a true positive rate of 93%, according to linear discriminant analysis. GDM subjects presented higher levels of As, Cd, and Hg, indicating that these elements may disturb insulin metabolism and promote the development of GDM. Therefore, we conclude that systematic monitoring of trace elements followed by multivariate modeling in women planning pregnancy should be carried out to prevent the development of GDM.

Metal Risk Assessment Study of Canned Fish Available on the Iranian Market.

Iran is the largest fishery producer in the region reaching nearly 1 million tons. Fish provide a good many nutrients that are beneficial for our health. Due to significant deposits of xenobiotics in the water environments, however, fish may also be a source of non-essential metals, causing a variety of disorders. The main challenges to Iranian fisheries are environmental pollution and quality control, so this study aims to estimate the concentration of cadmium (Cd), mercury (Hg), nickel (Ni), and lead (Pb) in canned tuna fish produced and consumed in Iran. We studied four popular brands (N = 4 × 20) with ICP-MS and then looked at the concentrations and calculated the risk assessment parameters. We found that the lowest concentration was observed for Cd (18 µg/kg) and the highest for Ni (132 µg/kg). Among the brands studied, Pb concentrations differed most (42.0 to 113.3 µg/kg) and Hg levels were more consistent (24.0 and 39.4 µg/kg). The concentrations of Cd, Hg, and Pb in all the brands tested were below EU permissible thresholds. The intake estimation risk assessment parameters (EDI, contribution to PTWI, and CR) and non-cancer risk assessment parameters based on reference doses (THQ and HI) demonstrated the safety of tested products in respect to all metal concentrations studied, while the parameters regarding the toxic effects (MoE, and ILCR) showed that the consumption might cause health risks in terms of Cd (ILCR), Ni (ILCR), and Pb (MoE). The consumption of the canned fish studied should therefore be maintained at a reasonable level (2-5 meals containing fish weekly), so that it may provide necessary nutrients, while avoiding the health risk due to metal content.

Cadmium and chromium levels in water and edible herbs in a risk assessment study of rural residents living in Eastern Iran.

In arid and semi-arid regions of Iran, water is supplied by qanats, underground channels where pollution is suspected, but unestablished. The aim of this study was thus to run a risk assessment study regarding the levels of cadmium (Cd) and chromium (Cr) in qanat water and edible herbs (Adiantum capillus-verenis, Chara globularis and Plantago lanceolata) growing in qanats in 14 villages in South Khorasan Province in Iran between April and August 2018. Samples were collected in qanats from the same sampling points, and after mineralization in nitric and perchloric acids were analyzed for metal concentrations by means of atomic absorption spectrometry. Concentrations of Cd and Cr found in water were not high (0.028 and 1.091 µg L-1, respectively) and contamination parameters revealed no pollution. The ingestion rate of water and the exposure frequency to metals were the most relevant variables in the model of a sensitivity analysis, but the Hazard Quotient indicated no risk of non-carcinogenic health problems to consumers of the water. The Carcinogenic Risk parameter suggested, however, that there is a risk of these consumers' developing cancer. Concentrations found in herbs were higher than in water but remained below permissible thresholds. Hazard Quotient values of three species studied in the case of children and A. capillus-verenis in the case of adults indicated a potential non-carcinogenic health risk linked with eating them. The study reveals that further research to include many of the qanats across Iran should be carried out to verify the scale of the risk suggested. Graphical abstract.

Urinary Metal Levels with Relation to Age, Occupation, and Smoking Habits of Male Inhabitants of Eastern Iran.

In low-income and middle-income countries such as Iran, smoking is becoming increasingly popular, especially among young people. This has led to additional exposure to a variety of substances, including metals which may exert a toxic influence and lead to severe diseases. In order to evaluate the influence of smoking on metal concentrations, a case-control study of levels of metal in urine was carried out in smokers (n = 64) and non-smokers (n = 35) from the city of Birjand (Iran). They were divided according to their age and socioeconomic status. Concentrations of cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), nickel (Ni), lead (Pb), and zinc (Zn) were measured using ET-AAS. We found higher concentrations of Cd (0.03 vs. 0.12 µg/L), Co (0.6 vs. 1.22 µg/L), and Cr (14.00 vs. 18.17 µg/L) in the urine of smokers. Age and occupation are factors that also influence the levels of metals. Young smokers demonstrate higher Cd and Pb levels than other age groups. It would also appear that public sector workers and self-employed are the sectors most susceptible to high levels of metals.

Metal concentrations in archaeological and contemporary mussel shells (Unionidae): Reconstruction of past environmental conditions and the present state.

Freshwater mussels are widely used in the monitoring of pollution because they are filter-feeding, long-lived animals that tend to accumulate metals in their shells. The temporal scale of such studies can reach thousands of years, since the composition of shells preserves them against decay. This allows us to reconstruct past environmental conditions and to compare current environmental conditions to those prevalent thousands of years ago. Here we assessed metal concentrations (Ca, Cd, Cr, Cu, Fe, Hg, Ni, Pb and Zn) in recently harvested mussel shells and mussel shells found by archaeologists, and tested the hypothesis that levels of some metals are higher in today's shells, reflecting increasing anthropogenic impact. We observed lower metal concentrations (with the exception of Cd) in shells found by archaeologists (n = 35) than in recently harvested mussel shells (n = 14) (Unio crassus, Unio pictorum, Unio tumidus) in the same water bodies. There were no significant differences in metal levels among species in shells found by archaeologists, while in recently harvested mussels almost all metals for which we tested were found in their highest levels in Unio crassus. The results suggest that metal concentrations in prehistoric times were lower than today, which probably reflects human impact, rather than changes in the geochemical structure of rocks. The results also revealed that metal transfer between mussel shells and surrounding deposits does not occur. We therefore suggest that they might be successfully used as independent bioindicators.

Caffeine strongly improves motility parameters of turkey spermatozoa with no effect on cell viability.

The purpose of this study was to evaluate the impact of caffeine on turkey spermatozoa during in vitro incubation. Experimental samples were prepared by diluting the raw semen with nine different concentrations of caffeine - from 0.078125 mg/mL to 10 mg/mL. The individual motility parameters were evaluated by the Computer Assisted Semen Analyser (CASA) system, and the viability of spermatozoa was evaluated using eosin-nigrosin staining. Selected parameters were recorded at six time periods: 0, 1, 2, 3, 4 and 5 h at 5 °C and 41 °C. A significantly higher motility and progressive motility of spermatozoa (P < 0.01 and P < 0.001, respectively) was detected in the samples containing caffeine ranging from 0.15625 to 7.5 mg/mL as compared to the control sample at 5 °C. At an incubation temperature of 41 °C the positive effect of caffeine on motility parameters was observed only at the beginning of incubation (at times 0 and 1). The tested caffeine concentrations showed no significant effect on the viability of turkey spermatozoa at any time period of incubation. A higher percentage of dead spermatozoa was observed for incubation at 41 °C (from 5.96% to 11.1%) in comparison to 5 °C (from 1.62% to 5.79%). The results suggest that caffeine can be used as a suitable component of turkey semen extenders and has the potential to improve fertility.

Biogenic and Risk Elements in Wines from the Slovak Market with the Estimation of Consumer Exposure.

Wine consumption delivers macroelements and microelements necessary for the proper metabolism. On the other hand, wine can be an important source of toxic metals. The aim of this study was to estimate the concentrations of Ca, Cd, Cu, Fe, Hg, Mg, Ni, Pb, and Zn in the Slovak and non-Slovak wines. The concentration of metals was evaluated with respect to the type, the alcohol content, and the age of Slovak wine. The general scheme of concentrations found was as follows Ca > Mg > Fe > Zn > Pb > Cd > Ni > Cu > Hg. The type of wine and the alcohol content do not have a significant impact on metal concentrations. Also, the age of wine has no influence on the mean concentration of metals, except for Zn. Metal concentrations in Slovak and non-Slovak wines indicate similar contents of metals, except for Ni. The contribution to both dietary reference values (DRVs) and provisional tolerable weekly intake (PTWI) evaluations in the Slovak wine suggested low dietary exposure to Ca, Cu, Fe, Mg, Ni, Zn, Cd, Hg, and Pb, respectively. However, we do not suggest that the consumption of all Slovak wines is healthy. The maximum Pb concentrations in Slovak wines exceed the maximum permitted level proposed by the European Commission. This might be proved by the results of the margin of the exposure (MOE) value evaluation in the samples containing the maximum Pb concentrations, showing a high risk of CKD and SBP in high and extreme consumption groups.

Levels of Metals in Kidney, Liver, and Muscle Tissue and their Influence on the Fitness for the Consumption of Wild Boar from Western Slovakia.

Due to environmental pollution, wild animals are exposed to various pollutants. Some game animals, such as wild boars are used by people for food, but their meat is not evaluated regarding pollution transfer, since they are unavailable on the official market. The aim of this paper is to present the concentrations of chosen metals (Cd, Co, Cu, Hg, Pb, and Zn) in the kidneys, liver, and muscles of wild boars (n = 40) hunted in eastern Slovakia, as derivatives of physiological distribution and anthropogenic pollution. We found that sex was not a statistically significant factor for metal concentrations. Tissue differences were observed for all the metals studied except for Co. Cd, Cu, and Hg showed the highest median concentrations in kidney tissue with the lowest in muscle tissue (2.73, 3.78, and 0.061 µg/g w.w., respectively). The highest Zn median concentration was noted in the liver tissue with the lowest in muscle tissue. Co and Cu concentrations varied according to the age groups. Correlations between metal concentrations in muscle and kidney tissue were not especially strong; such relationships were not found in liver tissue. Among all the potential relationships of the given metal concentrations between tissues, the only significant relationship, albeit weak, was noted for Pb in muscle and liver tissue. The concentrations found seem not to be extremely high, but according to EU maximum permitted residue levels for Cd and Pb concentrations in meat, none of the samples studied was fully fit for human consumption. TWI and risk was also excessive for both metals.

Relationship between air pollution and metal levels in cancerous and non-cancerous lung tissues.

We aimed to check the relationships between levels of metals (Ca, Cd, Cu, Fe, Hg and Zn) in cancerous and non-cancerous lung tissues and their link to air pollution, expressed as particulate matter (PM) concentrations. The study also examines the influence on metal concentration in the lung tissue of patients' sex and the distance of their homes from the nearest emitter. We found that the general pattern of ascending concentrations in tumor tissue was as follows: Hg < Cd < Cu < Ca < Zn < Fe. In non-affected lung tissue the order of concentrations of Ca and Fe was reversed. With the exception of Cd and Cu, levels of metals were found in higher accumulations in non-cancerous tissue (e.g., Fe 326.423 and Ca 302.730 µg/g d.w) than in tumorous tissue (Fe 150.735 and Ca 15.025 µg/g d.w). Neither the PM10 (PM of a diameter of 10 µm) concentration nor sex revealed any connection with metal concentrations. The shorter the distance from the emitter, the higher the metal concentrations that tended to be observed for almost all metals, but a statistically significant (but weak) relationship was noted only for Cu in tumor tissue (rs: -0.4869).

Trace element concentrations in feathers of five Anseriformes in the south of the Caspian Sea, Iran.

Birds are susceptible to environmental changes, which make them particularly important as indicators of environmental contamination, including metal concentrations. In the present study, the concentrations of arsenic (As), cadmium (Cd), chromium (Cr), iron (Fe), lead (Pb), manganese (Mn), nickel (Ni), and zinc (Zn) in the tail and flight feathers of greylag goose, mallard, pintail, pochard, and wigeon were investigated from the south of the Caspian Sea in Iran by the electrothermal atomic absorption spectrometry (ET-AAS) method. The trend of metal concentrations in both types of feathers of all the examined species was as follows: Fe < Zn < Mn < Cd ∼ Cr ∼ Ni ∼ Pb < As. The interspecies variation in concentrations of almost all the studied metals was observed, as well as the significant differences between feather types. The only exception was Ni, the medians of which were comparable in tail and primaries. Correlations of concentrations of Cd, Mn, Ni, Pb, and Zn in primaries and tail feathers were positive and statistically significant. Elevated concentrations of Cd, Cr, Mn, and Pb were noted so the possibility of environmental contamination of the area is suspected.

Cadmium, lead and mercury concentrations and their influence on morphological parameters in blood donors from different age groups from southern Poland.

Due to industrial development, environmental contamination with metals increases which leads to higher human exposure via air, water and food. In order to evaluate the level of the present exposition, the concentrations of metals can be measured in such biological materials as human blood. In this study, we assessed the concentrations of cadmium (Cd), mercury (Hg) and lead (Pb) in blood samples from male blood donors from southern Poland (Europe) born in 1994 (n=30) and between 1947 and 1955 (n=30). Higher levels of Pb were seen in the group of older men (4.48 vs 2.48µg/L), whereas the Hg levels were lower (1.78 vs 4.28µg/L). Cd concentrations did not differ between age groups (0.56µg/L). The levels of Cd and Pb in older donors were significantly correlated (Spearman R 0.5135). We also observed a positive correlation between the number of red blood cells (RBC) and Hg concentrations in the older group (Spearman R 0.4271). Additionally, we noted numerous correlations among morphological parameters. Based on our results, we can state that metals influence the blood morphology and their concentrations in blood vary among age groups.