Trace element levels in blood and associated factors in adults living in the metropolitan area of São Paulo, Brazil

Heavy Metal and Trace Element Levels in Hair Samples from Fishermen in Turkey: The Fish/Ermen Heavy Metal Study (FHMS)

Toxic chemicals from polluted seas can enter the human body through seafood consumption and cause health problems. The aim of this study was to evaluate the levels of selected heavy metals and trace elements among fishermen who frequently consumed seafood and controls who consumed seafood less frequently in four provinces on the shores of the Sea of Marmara, which is heavily polluted by industrial activities. Fourteen elements (antimony, arsenic, cadmium, chromium, copper, iron, lead, manganese, mercury, nickel, selenium, strontium, vanadium, and zinc) were analyzed in hair samples using the inductively coupled plasma-mass spectrometer method. Levels of arsenic (0.147 ± 0.067 µg/g vs. 0.129 ± 0.070 µg/g, p = 0.025), chromium (0.327 ± 0.096 µg/g vs. 0.269 ± 0.116 µg/g, p < 0.01), nickel (0.469 ± 0.339 µg/g vs. 0.403 ± 0.368 µg/g, p = 0.015), strontium (1.987 ± 1.241 µg/g vs. 1.468 ± 1.190 µg/g, p < 0.01), and zinc (103.3 ± 43.1 µg/g vs. 92.7 ± 37.4 µg/g, p = 0.047) were higher in the fisherman group than in the control group. No difference was found between the groups in terms of other elements. The findings suggest that heavy metal-trace element contamination in the Sea of Marmara may increase the exposure levels of individuals to some chemicals through seafood consumption.

Plasma Concentration of Essential and Toxic Trace Elements After Brazil Nut Intake: Results from a Randomized Controlled Trial

Brazil nut (BN) is a good source of essential nutrients, but little is known about the content of other components, such as toxic elements. Moreover, the high consumption of BN could probably contribute to increased levels of toxic and essential elements in the blood. Thus, this study aimed to evaluate the concentration of essential and toxic trace elements in BN and their concentration in plasma of obese women after regular intake of BN. A randomized controlled clinical trial was carried out with 55 subjects that were randomly assigned to either the Brazil nut group (BN) (n = 29) or the control group (CO) (n = 26) and followed up for 2 months. The BN group consumed one unit of Brazil nut per day, and the CO group did not receive any intervention. The concentration of essential elements (zinc, copper, manganese, and cobalt) and toxic (barium, lead, and cadmium) in BN samples and plasma of obese women (before and after the intervention) were determined by inductively coupled plasma mass spectrometry. Barium followed by copper, and manganese were the trace elements present in higher amounts in Brazil nuts. After the BN intervention period was observed an increase in plasma cadmium (p = 0.002) and a reduction of plasma manganese (p < 0.001) levels. In conclusion, our findings suggest that the regular consumption of BN from the Brazilian Amazon rainforest contributes to the intake of essential trace elements and can be considered safe regarding the content of heavy metals.

Environmental exposure of the general population to cadmium as a risk factor of the damage to the nervous system: A critical review of current data

Nowadays, more and more attention has been focused on the risk of the neurotoxic action of cadmium (Cd) under environmental exposure. Due to the growing incidence of nervous system diseases, including neurodegenerative changes, and suggested involvement of Cd in their aetiopathogenesis, this review aimed to discuss critically this element neurotoxicity. Attempts have been made to recognize at which concentrations in the blood and urine Cd may increase the risk of damage to the nervous system and compare it to the risk of injury of other organs and systems. The performed overview of the available literature shows that Cd may have an unfavourable impact on the human's nervous system at the concentration >0.8 μg Cd/L in the urine and >0.6 μg Cd/L in the blood. Because such concentrations are currently noted in the general population of industrialized countries, it can be concluded that environmental exposure to this xenobiotic may create a risk of damage to the nervous system and be involved in the aetiopathogenesis of neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease, as well as worsening cognitive and behavioural functions. The potential mechanism of Cd neurotoxicity consists in inducing oxidative stress, disrupting the activity of enzymes essential to the proper functioning of the nervous system and destroying the homoeostasis of bioelements in the brain. Thus, further studies are necessary to recognize accurately both the risk of nervous system damage in the general population due to environmental exposure to Cd and the mechanism of this action.

Determinants of blood and saliva lead concentrations in adult gardeners on urban agricultural sites

Soil Pb concentrations at urban agriculture sites (UAS) commonly exceed recommended safe levels. There is a lack of evidence regarding uptake of Pb by gardeners using such sites for food crops. Our study aimed to elucidate whether gardening in soil with raised Pb levels results in Pb body burdens of concern to health, and to assess confounding factors influencing Pb body burden. Our cross-sectional case study measured Pb in saliva and blood of UAS gardeners (n = 43), soil and produce samples from their UAS, and home tap water. Blood and saliva Pb concentrations were compared with those from non-UAS gardener controls (n = 29). A health risk threshold of 5 µg dL^-1 blood Pb level (BLL) was selected in keeping with international guidance. Detailed surveys investigated individuals' anthropometrics and potential Pb exposures from diet, and historic and everyday activities. Saliva was not found to be a suitable biomarker of adult Pb exposure in this context. Predictors of higher BLLs were being older, being male and eating more root vegetables and shrub fruit. Eating more green vegetables predicted a lower BLL, suggesting a protective effect against Pb uptake. UAS gardeners' BLLs (geometric mean 1.53; range 0.6-4.1 µg dL^-1) were not significantly higher (p = 0.39) than the control group (geometric mean 1.43; range 0.7-2.9 µg dL^-1). All BLLs were below 5 µg dL^-1 except one resulting from occupational exposure. Having paired the UAS gardeners with closely matched controls, we found Pb in UAS soils (with range 62-1300 mg kg^-1from common urban sources) unlikely to pose an additional risk to adult health compared to their neighbours who did not access UAS. As such, other Pb sources may be the dominant factor controlling BLL.

Fundão tailings dam failure in Brazil: Evidence of a population exposed to high levels of Al, As, Hg, and Ni after a human biomonitoring study

BACKGROUND

On November 5th, 2015, the Fundão mine tailings dam in Minas Gerais State, Brazil, failed, releasing more than 50 million m³ of mud, rich in toxic metals. After that, a massive environmental disaster began with the mud wave flowing more than 600 km, until the mouth of Doce River, in Espírito Santo State, and finally reaching the Atlantic Ocean. A vast area was contaminated, affecting the ecosystem and several communities. Despite the tremendous environmental disaster, little is known concerning the population's exposure to toxic elements yet.

METHODS

Thus, a cross-sectional study was for the first time conducted in three communities directly affected by the disaster (Regência, Povoação, and Campo Grande) in Espírito Santo State, to evaluate the levels of 11 chemical elements (Al, As, Cd, Co, Cu, Hg, Mn, Ni, Pb, Se, and Zn) in blood. Sample analysis (n = 300) was performed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS).

RESULTS

Our data show high levels of exposure to Al, As, Hg, and Ni. Mean values in blood were 60 μg/L (ranging from 9 to 434 μg/L), 10.9 μg/L (ranging from 5.81 to 269 μg/L), 6.4 μg/L (ranging from 0.05 to 103 μg/L) and 2.7 μg/L (ranging from 0.08 to 21 μg/L) for Al, As, Hg and Ni, respectively. Moreover, after applying a multiple regression model, we found community, drinking water, fish, seafood consumption, and smoking habits associated with metal/metalloid levels in their body. Well and tap water intake were identified as important sources of exposure to aluminum and nickel.

CONCLUSIONS

Our findings represent health risks to the groups living in the areas affected by the tailings dam failure, calling for further studies to evaluate the potential health effects of high exposure to metals and remediation actions from public health Brazilian authorities.

Determination of 14 trace elements in blood, serum and urine after environmental disaster in the Doce River basin: Relationship between mining waste and metal concentration in the population

BACKGROUND

Exposure to chemical substances after an environmental disaster can cause both toxic effects and changes in the health status of people who live in or have proximity to environments of this nature, so that the concern with populations is growing.

METHODS

In this cross-sectional study, blood, serum and urine samples were collected from 100 volunteers from Santo Antônio do Rio Doce, eight from Ilha das Pimentas and 50 from the control group; and analyzed by inductively coupled plasma mass spectrometry for biomonitoring of Al, As, Ba, Cd, Co, Cu, Cr, Fe, Hg, Mn, Ni, Se, Pb, Zn. In addition, a comprehensive questionnaire was applied to collect demographic and socioeconomic information, as well as lifestyle.

RESULTS

The concentrations of As, Al, Cd, Ni and Mn were above the reference value in some biological matrices, with more pronounced exposure in Ilha das Pimentas. The concentrations of As, Cd, Cu, Co, Pb and Zn showed statistical differences regarding gender in the different biological matrices. The trace elements in the blood, serum and urine showed significant correlations when considering age and habits such as the consumption of cigarettes, alcoholic beverages and fish. The main correlations were observed between Co, Cr, Mn, Ni and Pb in the blood and cigarette consumption.

CONCLUSION

This is the first study in these regions after the environmental disaster and confirmation of the diagnosis and health care of the participants should be promoted for clinical investigation and the eventual need for treatment. Human biomonitoring demonstrated high concentrations of some toxic elements, with more accentuated exposure in Ilha das Pimentas.

Biomonitoring of Exposure to Metals in a Population Residing in an Industrial Area in Brazil: A Feasibility Study

Background: Industries are sources of environmental pollutants. However, there are few human biomonitoring (HBM) studies in the vicinity of industrial areas. Thus, we evaluate the feasibility of conducting an HBM study to assess exposure to metals in an industrial area in Rio de Janeiro, Brazil. Methodology: A cross-sectional survey was conducted near a steel factory. Adults (exposed = 775; controls = 775) were randomly selected and sex-matched. Subjects were interviewed using a questionnaire and a 24 h dietary recall. Blood samples were collected to analyze metal concentrations, blood count, biochemical parameters, and thyroid hormones. The feasibility of the survey was assessed following guidelines. The descriptive analysis was performed for the first 250 participants (pilot study). Results: Adjustments were made to the survey execution, including age-matching, fieldwork team, questionnaire, blood collection, and research awareness. The complete questionnaire was answered by ≥97% of participants; metals were measured in ≥98% and clinical parameters in ≥89%, except thyroid hormones (13–44%). The average age and family income were of 50 years and USD 575/month, respectively. The participants had equal distribution among sexes: 50% had a medium education level, and 59% were nonwhite. Conclusion: This preliminary HBM study demonstrates feasibility for the total population, with results indicating representativeness of the target population.

Determination of 11 minerals in children using inductively coupled plasma mass spectrometry

BACKGROUND

Minerals play an important role in children's growth and cognition. In this study, our aim was to establish reference intervals of mineral level in Children of Liaoning province (China) and provide a reliable basis for future preventive healthcare guidelines.

METHODS

Random samples of 2217 healthy children aged 0-15 years who were referred for routine hospital laboratory examinations in the cities of Shenyang, Fushun, Fuxin, Benxi, Chaoyang and Lingyuan were invited to participate in the study. Serum levels of Calcium (Ca), Iron (Fe), Zinc (Zn), Magnesium (Mg), Copper (Cu), Manganese (Mn), Selenium (Se), Mercury (Hg), Nickel (Ni), Cobalt (Co), and Lithium (Li) were determined by inductively coupled plasma mass spectrometer(ICP-MS).

RESULTS

Sex-related significant differences in the serum concentrations of the Mg and Cu (P < 0.05). Age-related significant differences were found in serum levels of Ca, Fe, Zn, Mg, Cu and Mn (P < 0.05) and the concentrations of 9 minerals (Ca, Mg, Cu, Mn,Se,Hg,Ni,Co and Li in serum varied from season to season (P < 0.05). The Spearman correlation matrix of 11 minerals was shown as a heat map, the correlations between Ca-Zn, Ca-Mg, Fe-Zn, Fe-Se, Mn-Ni, Se-Hg, Se-Ni, Hg-Ni, and Ni-Co, Ni-Li were the strongest compared with others.

CONCLUSIONS

The reference intervals of serum 11 minerals for children should considering the sex, age and season, which may be useful for decisive diagnoses of abnormality of the 11minerals and the related diseases.

Heavy Metals and Trace Elements in Whole-Blood Samples of the Fishermen in Turkey: The Fish/Ermen Heavy Metal Study (FHMS)

Selected heavy metal-trace element (Ag, As, Ba, Cd, Cu, Hg, Pb, Sb, Se, Sr, and V) levels were determined by the ICP-MS method in whole-blood samples of fishermen and control group who accommodate in four provinces of the Marmara Sea. Mercury (1.267 ± 1.061 µg/L to 0.796 ± 0.853 µg/L) and lead (17.8 ± 9.0 µg/L to 12.0 ± 6.83 µg/L) levels were higher in the fishermen group than that of control group (p < 0.001 for both). There was no difference between the fishermen group and the control group in terms of whole-blood levels of other elements. Total monthly fish consumption was 9340.4 gr in the fishermen group and 326.4 gr in the control group, and the difference between the groups was significant (p < 0.001). There was no difference between the groups in terms of having amalgam dental filling (p > 0.05). The results suggest that consuming high amounts of sea products caught from the Marmara Sea is a source for some heavy metals such as mercury and lead, which poses a public health risk. Unlike the control group, the positive correlation between arsenic, copper, and strontium levels and age in fishermen can also be evaluated as an indicator of chronic exposure.

Higher blood cadmium level is associated with greater cognitive decline in rural Chinese adults aged 65 or older

Cadmium (Cd) exposure has been reported to have neurotoxic effects in animal studies and associated with increased Alzheimer's Disease mortality and lower cognitive function in cross-sectional and case-control studies. However, no results from longitudinal studies on Cd and cognitive decline are available. In this prospective cohort study, we recruited 1867 participants aged 65 years or older from rural areas in China, blood Cd and cognitive function were measured at baseline (2010-2012), and 1554 participants completed cognitive function tests during a 3-year follow-up (2013-2015). Cognitive function was evaluated using nine standardized cognitive tests: The Community Screening Instrument for Dementia, the CERAD Word List Learning, Word list recall, IU Story Recall, Animal Fluency Test, Boston Naming Test, Stick Design, Delayed Stick Design and the IU Token Test. Analysis of covariance models and logistic regression models were used to determine the association between Cd and standardized cognitive decline adjusting for covariates. The median blood Cd concentration of this study population was 2.12 μg/L, and the interquartile range was 1.42-4.64 μg/L. Significant association of higher Cd levels with lower cognitive scores were observed in five individual cognitive tests (Delayed Stick Design Test, Boston Naming Test, CERAD Word List Learning Test, Word List Recall Test and IU Story Recall Test) and the composite cognitive score adjusting for multi-covariates at baseline. Higher Cd levels were significantly associated with greater 3-year cognitive decline in Delayed Stick Design Test, Boston Naming Test, IU Token Test, Word List Recall Test and Composite cognitive score. For these cognitive tests, participants in the top two Cd quartile groups had significantly greater decline than those in the lowest Cd quartile group, while the two lowest Cd quartile groups were not significantly different. Our findings suggest that higher Cd exposure is associated with greater cognitive decline in older Chinese adults.

Blood cadmium levels and sources of exposure in an adult urban population in southern Brazil

BACKGROUND

Cadmium (Cd) is a toxic metal that is widely present in the environment due to geologic and anthropogenic sources. Exposures to high Cd levels may cause nephrotoxicity, carcinogenicity, pulmonary and cardiovascular disease, among others. The goal of this study was to investigate in an adult urban population whether an association exists between sources and levels of Cd exposure and blood Cd concentrations.

METHODS

Using a census-based design, a total of 959 adults, aged 40 years or older, were randomly selected. Information on socio-demographics, dietary, and lifestyle background was obtained by household interviews. Blood Cd levels were measured by inductively coupled-plasma mass spectrometry. Geometric means (GM) (95% CI) and the 50th percentile were determined, stratified by sex, age, race, education, income class, smoking status, consumption of vegetables, red meat and milk, occupation and blood pressure. To assess the association between Cd exposure and the aforementioned variables, we estimated the geometric mean ratio (GMR) (95%CI) of blood Cd concentrations.

RESULTS AND CONCLUSION

The geometric mean (95%CI) of blood Cd levels in the total population was 0.25 (0.22, 0.27) ug/dL. In a univariate analysis, significantly higher blood Cd levels were found in men (p < 0.001), current and former smokers (p < 0.001), alcohol drinkers (p < 0.001), those who never or almost never consumed milk (p < 0.001), and in subjects with higher diastolic blood pressure (p = 0.03). Significant correlations were found between the number of cigarettes consumed daily and blood Cd levels. Multivariate analysis confirmed higher blood Cd concentrations were associated with alcohol consumption (GMR 95%CI = 1.28, 1.04-1.59) and in former and current smokers (GMR 95% IC = 1.33, 1.06-1.67 and 4.23, 3.24-5.52, respectively). Our results shed novel information on variables associated with blood Cd levels in an urban Brazilian population, and should encourage additional research to prevent environmental Cd exposure, both in Brazil and globally.

Health effects of arsenic exposure in Latin America: An overview of the past eight years of research

Studies conducted over the past eight years in Latin America (LA) have continued to produce new knowledge regarding health impacts of arsenic (As) in drinking water. We conducted a systematic review of 92 peer-reviewed English articles published between 2011 and 2018 to expand our understanding on these health effects. Majority of the LA studies on As have been conducted in Chile and Mexico. Additional data have emerged from As-exposed populations in Argentina, Bolivia, Brazil, Colombia, Ecuador, and Uruguay. The present review has documented recent data on the biomarkers of As exposure, genetic susceptibility and genotoxicity, and risk assessment to further characterize the health effects and exposed populations. Some recent findings on the associations of As with bladder and lung cancers, reproductive outcomes, and declined cognitive performance have been consistent with what we reported in our previous systematic review article. We have found highly convincing evidence of in utero As exposure as a significant risk factor for several health outcomes, particularly for bladder cancer, even at moderate level. New data have emerged regarding the associations of As with breast and laryngeal cancers as well as type 2 diabetes. We observed early life As exposure to be associated with kidney injury, carotid intima-media thickness, and various pulmonary outcomes in children. Other childhood effects such as low birth weight, low gestational age, anemia, increased apoptosis, and decreased cognitive functions were also reported. Studies identified genetic variants of As methyltransferase that could determine susceptibility to As related health outcomes. Arsenic-induced DNA damage and alteration of gene and protein expression have also been reported. While the scope of research is still vast, the substantial work done on As exposure and its health effects in LA will help direct further large-scale studies for more comprehensive knowledge and plan appropriate mitigation strategies.

A comparative study of cadmium levels in blood from exposed populations in an industrial area of the Amazon, Brazil

Chemical pollution from industrial sources is one of the main problems affecting the environment. In urban areas, the emission of toxic gases and particulates to the atmosphere can damage human health. Cadmium (Cd) is one of the most ecotoxic metals among these pollutants, even at low concentrations. In this study, environmental exposure to Cd was evaluated from the Cd blood levels (CdB) of the human populations living in two Amazonian districts. The first was Bairro Industrial (BIN), which is located next to the industrial complex in Barcarena City, while the second was Vila do Beja (VBJ), a control group located in the farthest area from industrial activities in Abaetetuba City. Sectional and comparative studies were applied for both districts. Sampling (N = 469) occurred in 2012 and 2013. Gender, age, residence time, drinking water source, alcohol consumption, and smoking were used as independent variables. CdB levels were analyzed by induced coupled plasma mass spectrometry (ICP-MS). In BIN, geometric mean and median CdB levels were 0.27 and 0.43 μg∙L^-1, respectively (range: ≤0.03-17.49 μg∙L^-1), while in VBJ these were 0.19 and 0.23 μg∙L^-1 (range: ≤0.03-2.38 μg∙L^-1). The higher CdB concentration in the blood of people from BIN was similar to levels previously found in people living near other industrial areas, and showed that the BIN residents were more exposed to Cd pollution. The studies showed the need for surveillance actions to evaluate possible routes of exposure, avoiding the future worsening of the health of the population living next to industrial areas in the Amazon.

Simultaneous analysis of 25 trace elements in micro volume of human serum by inductively coupled plasma mass spectrometry (ICP-MS)

INTRODUCTION

In recent years, trace elements have gained importance as biomarkers in many chronic diseases. Unfortunately, the requirement for sample volume increases with the extent of investigation either for diagnosis or elucidating the mechanism of the disease. Here, we describe the method development and validation for simultaneous determination of 25 trace elements (lithium [Li], beryllium [Be], magnesium [Mg], aluminium [Al], vanadium [V], chromium [Cr], manganese [Mn], iron [Fe], cobalt [Co], nickel [Ni], copper [Cu], zinc [Zn], gallium [Ga], arsenic [As], selenium [Se], rubidium [Rb], strontium [Sr], silver [Ag], cadmium [Cd], caesium [Cs], barium [Ba], mercury [Hg], thallium [Tl], lead [Pb], uranium [U]) using only 20 μL of human serum.

METHODS

Serum samples were digested with nitric acid and hydrochloric acid (ratio 1:1, v/v) and analysed by inductively coupled plasma-mass spectrometry (ICP-MS). Seronorm®, a human-derived serum control material was used as quality control samples.

RESULTS

The coefficient of variations for both intra- and inter-day precisions were consistently <15% for all elements. The validated method was later tested on 30 human serum samples to evaluate its applicability.

CONCLUSION

We have successfully developed and validated a precise and accurate analytical method for determining 25 trace elements requiring very low volume of human serum.

An overview of the current progress, challenges, and prospects of human biomonitoring and exposome studies

Human Biomonitoring (HB), the process for determining whether and to what extent chemical substances penetrated our bodies, serves as a useful tool to quantify human exposure to pollutants. In cases of nutrition and physiologic status, HB plays a critical role in the identification of excess or deficiency of essential nutrients. In pollutant HB studies, levels of substances measured in body fluids (blood, urine, and breast milk) or tissues (hair, nails or teeth) aid in the identification of potential health risks or associated adverse effects. However, even as a widespread practice in several countries, most HB studies reflect exposure to a single compound or mixtures which are measured at a single time point in lifecycle. On the other hand, throughout an individual's lifespan, the contact with different physical, chemical, and social stressors occurs at varying intensities, differing times and durations. Further, the interaction between stressors and body receptors leads to dynamic responses of the entire biological system including proteome, metabolome, transcriptome, and adductome. Bearing this in mind, a relatively new vision in exposure science, defined as the exposome, is postulated to expand the traditional practice of measuring a single exposure to one or few chemicals at one-time point to an approach that addresses measures of exposure to multiple stressors throughout the lifespan. With the exposome concept, the science of exposure advances to an Environment-Wide Association Perspective, which might exhibit a stronger relationship with good health or disease conditions for an individual (phenotype). Thus, this critical review focused on the current progress of HB and exposome investigations, anticipating some challenges, strategies, and future needs to be taken into account for designing future surveys.

Assessment of 12 Metals and Metalloids in Blood of General Populations Living in Wuhan of China by ICP-MS

Assessment of trace element levels in general population from the specific area is of importance for nutritional and occupational monitoring. In the current study, baseline blood levels of 12 toxic and/or essential metals and metalloids, including arsenic (As), cadmium (Cd), lead (Pb), mercury (Hg), chromium (Cr), thallium (Tl), manganese (Mn), copper (Cu), Zinc (Zn), calcium (Ca), iron (Fe), and magnesium (Mg), in general populations (n = 477) of Wuhan in central China were investigated by using inductively coupled plasma mass spectrometry (ICP-MS). The geometric means for As, Cd, Pb, Hg, Cr, Tl, Mn, and Cu were measured as 2.25, 0.70, 17.84, 1.90, 0.36, < 0.05, 12.40, and 783.76 μg/L, respectively. The geometric means for Zn, Ca, Fe, and Mg were 5.85, 56.66, 488.98, and 39.44 mg/L, respectively. We found the men had higher blood As, Pb, Hg, Zn, Fe, and Mg levels but had lower blood Cu and Ca levels than the women (p < 0.05). Age-related difference were found for blood Cu, Zn, Ca, Mg, Pb, Mn, As, Cd, and Hg levels (p < 0.05). Moreover, many metal concentrations were found correlated, with the strongest correlations between the pairs Fe-Mg (r = 0.57), Fe-Zn (r = 0.42), As-Hg (r = 0.46), Ca-Cu (r = 0.34), Pb-Hg (r = 0.36), Pb-Cd (r = 0.31), Pb-As (r = 0.25), and Ca-Fe (r = - 0.23). Compared with reports from other countries, most of our results were consistent, except that As Pb, Hg, Mn, and Cu showed different blood levels with European, Korea, or Beijing areas. Our study would be of importance for nutritional, environmental, and/or occupational monitoring of these metals in human.

Simultaneous determination of metabolic and elemental markers in methamphetamine-induced hepatic injury to rats using LC-MS/MS and ICP-MS

Methamphetamine (METH) is one of the most highly addictive illicit drugs abused all over the world. Much evidence indicates that METH abuse leads to major toxicity, medical consequences, and even severe public health consequences. Existing studies usually focus on the pathomechanism of METH-induced toxicity; therefore, data on metabolites and elements correlating with particular toxicity remain scarce. The objective of the present study is to develop appropriate analytical procedures to identify the differential metabolic and elemental biomarkers on METH-induced hepatic injury to rats. The rats were administrated with METH (15 mg/mL/kg, two times per day) via intraperitoneal (i.p.) injections for four consecutive days. The alanine aminotransferase and aspartate aminotransferase activity levels of in the rat serum of the METH group increase significantly compared with those of the control group, suggesting obvious hepatic injury. The results are further confirmed by the histopathological microscopic observation. A total of 18 small molecular metabolites and 19 elements are selected to perform the simultaneous quantification based on the combination of liquid chromatography coupled with tandem mass spectrometry and inductively coupled plasma mass spectrometry. Sample preparation was optimized to cover all the analytes. Both methods are optimized and validated according to developed guidelines such as limits of detection, limits of quantification, linearity, precision, and recovery. All the obtained data are within the satisfactory range. The normalized data were processed according to the partial least squares discrimination analysis (PLS-DA) model. Five differential metabolic and six elemental markers are identified in rat plasma based on the variable importance in projection (VIP) (> 1) and t test results. Overall, the results obtained in this study demonstrate the developed methods are suitable for simultaneous determination of metabolic and elemental markers in the hepatic injury to rats induced by METH. Graphical abstract.

Mercury at environmental relevant levels affects spermatozoa function and fertility capacity in bovine sperm

Over the last several years human sperm quality was found to be significantly reduced and the role environmental contaminants play in this phenomenon remain to be determined. Mercury (Hg) is one of the most widespread contaminants; however the correlation between metal exposure and adverse consequences on human and animals fertility are not completely established. The aim of this study was to determine the effects of direct exposure to inorganic Hg on male gametes using spermatozoa (bovine sperm) which characteristically resemble human sperm. Sperm were divided and incubated for 0.5, 1 or 2 h at low levels of Hg: i) Control: without exposure; ii) Hg8 nM: mercury chloride (HgCl₂) at 8 nM and iii) Hg8 μM: HgCl₂ at 8 μM. Sperm kinetics, morphology, sperm membrane integrity, and in vitro fertilization were assessed. In addition the levels of reactive oxygen species (ROS), lipid peroxidation and total antioxidant capacity were measured. Hg exposure for 2 h impaired sperm morphology and membrane integrity as well as kinetic parameters including curvilinear velocity and straight-line velocity, which are needed for fertilization as evidenced by the reduced fertilization rate in 8 μM Hg-treated gametes. Hg enhanced oxidative stress in male sperm as reflected by elevated levels of ROS and lipid peroxidation and decreased antioxidant capacity. Data demonstrated that low levels of Hg when incubated with spermatozoa are sufficient to increase oxidative stress, adversely affect sperm quality parameters, subsequently impairing sperm fertility capacity.

Home-based and informal work exposes the families to high levels of potentially toxic elements

The city of Limeira presents a relevant productive chain of jewelry and fashion jewelry, including a scenario of outsourcing informal home practices. It is highly complex to understand the potentially toxic elements (PTE: Cr, Mn, Ni, Cu, Zn, As, Cd, Sn, Sb, Hg, and Pb) exposures of the workers because this productive chain encompasses households. This study aimed to investigate the associations between blood PTE levels and informal work in the home environment. Fifty-two families divided into Exposed group (n = 112) and Control group (n = 53) were included. Families' blood (n = 165) and welder's breathing zone air samples (n = 9) were collected and PTEs concentrations were determined by ICP-MS. Questionnaires were applied to collect sociodemographic information and workplace details. Principal component analysis, Mann-Whitney test, cluster and a logistic regression analysis based on environment-wide association studies (EWAS) were carried out. Ni, Cu, Zn, Cd and Pb concentrations in the air samples were higher than occupational guidelines. Eighty percent of the workers were female, and 43.5% of those females then worked as welder. A significant difference was found for Pb concentration between the exposed and control group (p < 0.0001) and between sexes (p = 0.0046). For Cu (p < 0.0001) and Sb (p = 0.0434), differences were found between the sexes. The receiver operating characteristic of the EWAS was 0.80, providing evidence of a potential model to associate exposure levels and occupational factors. PTEs concentrations in the air samples raised concerns, particularly for children, who were in the same exposure scenario. Inadequate work conditions were observed in the houses, revealing the need of public actions to protect these families.