Blood Hg Levels Research Articles

Genotoxic effects in island populations of Cartagena de Indias, Colombia due to environmental exposure to mercury and cadmium

Background Contamination of Cartagena Bay, Colombia with heavy metals such as mercury (Hg) and cadmium (Cd) presents a major environmental and public health concern, particularly for human communities residing on nearby islands and coastal areas. These populations face enhanced exposure risks owing to their traditional fishing practices and continuous interactions with polluted marine environments. This study aimed to evaluate the genotoxic effects of environmental exposure to Hg and Cd in populations from the island zone of the Cartagena district, Bolívar. Methods Ninety-four individuals from the four island communities (study group) and 30 individuals from the urban area of Cartagena (control group) participated in this study. The blood samples were collected to measure total mercury (T-Hg) and Cd concentrations, and a Buccal Micronucleus Cytome (BMCyt) assay was used to evaluate exposure effects. Results Cadmiun levels in the blood of the study group were within the normal range and comparable to those of the control group (p > 0.05). However, the study group exhibited significantly higher T-Hg levels (7.34 μg/L) compared to the control group (2.01 μg/L), surpassing the accepted limit. Moreover, the study group showed a higher incidence of DNA damage and cell death biomarkers (p < 0.05). Additionally, significant correlations were observed between total blood Hg levels and the frequencies of micronuclei, karyorrhexis, and karyolysis. Conclusion These results suggest that island populations of Cartagena are exposed to high levels of Hg and exhibit genotoxic damage, indicating a problem that must be addressed.

Genotoxic effects in island populations of Cartagena de Indias, Colombia due to environmental exposure to mercury and cadmium

Background Contamination of Cartagena Bay, Colombia with heavy metals such as mercury (Hg) and cadmium (Cd) presents a major environmental and public health concern, particularly for human communities residing on nearby islands and coastal areas. These populations face enhanced exposure risks owing to their traditional fishing practices and continuous interactions with polluted marine environments. This study aimed to evaluate the genotoxic effects of environmental exposure to Hg and Cd in populations from the island zone of the Cartagena district, Bolívar. Methods Ninety-four individuals from the four island communities (study group) and 30 individuals from the urban area of Cartagena (control group) participated in this study. The blood samples were collected to measure total mercury (T-Hg) and Cd concentrations, and a Buccal Micronucleus Cytome (BMCyt) assay was used to evaluate exposure effects. Results Cadmiun levels in the blood of the study group were within the normal range and comparable to those of the control group (p > 0.05). However, the study group exhibited significantly higher T-Hg levels (7.34 μg/L) compared to the control group (2.01 μg/L), surpassing the accepted limit. Moreover, the study group showed a higher incidence of DNA damage and cell death biomarkers (p < 0.05). Additionally, significant correlations were observed between total blood Hg levels and the frequencies of micronuclei, karyorrhexis, and karyolysis. Conclusion These results suggest that island populations of Cartagena are exposed to high levels of Hg and exhibit genotoxic damage, indicating a problem that must be addressed.

Brain gray matter volume of reward-related structures in Inuit adolescents pre- and postnatally exposed to lead, mercury and polychlorinated biphenyls

This study aimed to assess associations between prenatal and postnatal exposure to lead (Pb), mercury (Hg) and polychlorinated biphenyls (PCBs) and gray matter volume of key regions of the brain reward circuit, namely the caudate nucleus, putamen, nucleus accumbens (nAcc), the amygdala, the orbitofrontal cortex (OFC) and the anterior cingulate cortex (ACC). Structural magnetic resonance imaging (MRI) was conducted in 77 Inuit adolescents (mean age = 18.39) from Nunavik, Canada, who also completed the Brief Sensation Seeking Scale (BSSS-4) and Sensation Seeking – 2 (SS-2), two self-report questionnaires evaluating the tendency toward sensation seeking, which is a proxy of reward-related behaviors. Exposures to Pb, Hg and PCBs were measured in cord blood at birth, in blood samples at 11 years old and at time of testing (18 years old). Multivariate linear regressions were corrected for multiple comparisons and adjusted for potential confounders, such as participants’ sociodemographic characteristics and nutrient fish intake. Results showed that higher cord blood Pb levels predicted smaller gray matter volume in the bilateral nAcc, caudate nucleus, amygdala and OFC as well as in left ACC. A moderating effect of sex was identified, indicating that the Pb-related reduction in volume in the nAcc and caudate nucleus was more pronounced in female. Higher blood Hg levels at age 11 predicted smaller right amygdala independently of sex. No significant associations were found between blood PCBs levels at all three times of exposure. This study provides scientific support for the detrimental effects of prenatal Pb and childhood Hg blood concentrations on gray matter volume in key reward-related brain structures.

Exposure to low levels of heavy metals and chronic kidney disease in the US population: A cross sectional study.

Exposure to heavy metals (cadmium, mercury, and lead) has been linked with adverse health outcomes, especially their nephrotoxic effects at high levels of exposure. We conducted a replication study to examine the association of low-level heavy metal exposure and chronic kidney disease (CKD) using a larger NHANES data set compared to previous studies. The large cross-sectional study comprised 5,175 CKD cases out of 55677 participants aged 20-85 years from the 1999-2020 National Health and Nutrition Examination Survey [NHANES]. Logistic regression analysis was applied to estimate the associations between CKD and heavy metals [Cd, Pb, Hg] measured as categorical variables after adjusting with age, race, gender, socioeconomic status, hypertension, diabetes mellitus and blood cotinine level as smoking status. Compared to the lowest quartile of blood Cd, exposures to the 2nd, 3rd and 4th quartiles of blood Cd were statistically significantly associated with higher odds of CKD after adjustment for blood Pb and Hg, with OR = 1.79, [95% CI; 1.55-2.07, p<0.0001], OR = 2.17, [95% CI; 1.88-2.51, p<0.0001] and OR = 1.52, [95% CI; 1.30-1.76, p<0.0001] respectively. The 2nd, 3rd and 4th quartiles of blood Cd remained statistically significantly associated with higher odds of CKD after adjustment for blood cotinine level, with OR = 2.06, [95% CI; 1.80-2.36, p<0.0001], OR = 3.18, [95% CI; 2.79-3.63, p<0.0001] and OR = 5.54, [95% CI; 4.82-6.37, p<0.0001] respectively. Exposure to blood Pb was statistically significantly associated with higher odds of CKD in the 2nd, 3rd and 4th quartile groups, after adjustment for all co-variates (ag, gender, race, socio-economic status, hypertension, diabetes mellitus, blood cadmium, mercury, and cotinine levels) in all the four models. Blood Hg level was statistically significantly associated with lower odds of CKD in the 2nd quartile group in model 2, 3rd quartile group in model 1, 2 and 3, and the 4th quartile group in all the four models. Our findings showed that low blood levels of Cd and Pb were associated with higher odds of CKD while low blood levels of Hg were associated with lower odds of CKD in the US adult population. However, temporal association cannot be determined as it is a cross sectional study.

Association of exposure to multiple heavy metals during pregnancy with the risk of gestational diabetes mellitus and insulin secretion phase after glucose stimulation

Association of exposure to multiple heavy metals during pregnancy with the risk of gestational diabetes mellitus and insulin secretion phase after glucose stimulation

Mediating role of systemic inflammation in the association between heavy metals exposure and periodontitis risk.

This study evaluated the mediating role of systemic inflammation in the association between exposure to heavy metals and periodontitis in a nationwide sample of adults. Pooled cross-sectional data from the National Health and Nutrition Examination Survey (NHANES 2009-2014) were used (n=8993). Periodontitis was defined by a full-mouth examination and classified as no/mild and moderate/severe (mod/sev) groups. Blood and urinary heavy metal levels were investigated, including cadmium (Cd), lead (Pb), and mercury (Hg). In addition, systemic inflammation was assessed using circulatory leukocytecounts and C-reactive protein (CRP) levels. Multivariable logistic regression analysis revealed the positive associations of blood and urinary levels of Cd and Pb with mod/sev periodontitis. In contrast,blood Hg levels did not show a significant association. The odds of having periodontitis were 1.233 and 1.311 times higher for each one-unit increment in Ln-transformed blood Cd (95% confidence interval [CI]: 1.109-1.371) and Pb (95% CI: 1.170-1.470), respectively. Mediation analysis suggested a 6.3% to 11.5% contribution of leucocyte counts in the association of blood Cd and Pb levels with periodontitis. Sensitivity analyses for urinary Cd levels yielded consistent mediating effects. However, no significant mediating effect of CRP was detected. Higher exposures to Cd and Pb were positively associated with periodontitis risk. These associations might be partially mediated by the elevated levels of leukocytes rather than CRP. Further longitudinal studies are needed to elucidate the discordant results of the systemic inflammatory biomarkers.

Antioxidant and hypercholesterolemia effects of Lagerstroemia speciosa ethanolic green and red leaf extracts against Lauric acid and ketogenic diets in female albino rats

The study investigates the therapeutic value of Lagerstroemia speciosa ethanolic green and red leaf extracts against Lauric acid (LA) and a Ketogenic diet (KGD) in Albino rats. Lauric acid is an important constituent in breast milk, forming nutritional factors and having various medicinal values. It is present in 6.2% of human breast milk, 3.1% of goat milk, and 2.9% in cow milk. It is also found in plant sources like coconut, cohune, and palm kernel oil. The Ketogenic diet uses fat, protein, and low carbohydrate for energy. The experimental groups were fed a Ketogenic diet for 21 days, with the treated groups showing a significant increase in blood cell count and Hg levels. The phytochemical profile reveals abundant phytoconstituents, including corosolic acid, lagerstroemin, and anthocyanin, at high levels. The study compared experimental groups fed with LELE Low Dose and High Dose (250 and 500 mg/kg body weight) and standard groups treated with KGD and Lauric acid. The treated groups showed significant elevations in biochemical parameters and increased blood cells and Hg levels. LELE's anti-hypercholesterolemia activity in KGD significantly reduced body weight, total lipid profile, and blood glucose in a dose-dependent manner. The study found that LELE is safe and non-toxic, with the treated group demonstrating dose dependence and decreased obesity.

Determinants affecting the blood mercury levels of preschool children in Shanghai, China: A cross-sectional study.

Infants and children are vulnerable to mercury (Hg)-induced toxicity, which has detrimental effects on their neurological development. This study measured blood Hg levels (BMLs) and identified potential factors influencing BMLs, including demographic and socioeconomic factors, lifestyle, and daily dietary habits, among 0 to 7-year-old children in Shanghai. Our study recruited 1474 participants, comprising 784 boys and 690 girls. Basic demographic and lifestyle information were obtained and blood Hg were analyzed using the Direct Mercury Analyzer 80. The blood Hg concentrations of children in Shanghai ranged from 0.01 to 17.20 μg/L, with a median concentration of 1.34 μg/L. Older age, higher familial socioeconomic status, higher residential floors, and a higher frequency of consuming aquatic products, rice, vegetables, and formula milk were identified as risk factors. Other potential influencing factors including the mother's reproductive history (gravidity and parity), smoking (passive smoking), supplementation of fish oil and calcium need to be further investigated. These findings can be useful in establishing appropriate interventions to prevent children's high blood Hg concentrations in Shanghai and other similar metropolitan cities.

Association of mercury exposure with the serum high-sensitivity C-reactive protein level in Korean adults.

Although there is evidence that mercury (Hg) exposure may be a potential risk factor for cardiovascular disease (CVD), few nationwide epidemiological researches have analyzed the association between blood Hg concentration and serum high-sensitivity C-reactive protein (hs-CRP) level as a biomarker of CVD. The present population-based national study was performed with data from the 2016-2017 National Health and Nutrition Examination Survey. In the total sample of 3,773 adults aged ≥20 years, the serum hs-CRP concentrations were 1.03 mg/L among participants in the lowest quartile of blood Hg level and 1.18 mg/L among those in highest quartile. The trend for the prevalence of a risky (>1.0 mg/L) hs-CRP level (moderate risk and high risk) was significantly related to an increased quartile blood Hg concentration. After adjustment for confounders, participants with the highest quartiles of blood Hg had increased odds of a risky (>1.0 mg/L) hs-CRP level (adjusted odds ratio = 1.34; 95% confidence interval, 1.02-1.77) compared with those with the lowest quartile of blood Hg. These findings demonstrate that a high blood Hg level increases the concentration of serum hs-CRP, a sensitive marker of chronic low-grade inflammation, and imply that the increased body burden associated with high blood Hg is a potential risk factor in the development of many inflammatory diseases, including CVD.

Maternal and fetal morbidity and mortality among pregnancies complicated by pre-eclampsia in Omdurman Maternity hospital, Sudan

Background: Maternal mortality and morbidity are one of the biggest problems worldwide. Every day approximately 830 women die from preventable causes related to pregnancy and child birth. Ninety nine percent of these deaths occur in developing countries of which more than half are in sub Saharan Africa and one third in South Asia. Preeclampsia may lead to prematurity, still birth, intrauterine growth retardation and perinatal death. Consequently early diagnosis of preeclampsia and close observation are imperative. Despite advances in medical practice pre-eclampsia still remains a leading cause of maternal and prenatal morbidity and mortality.This study was conducted at Omdurman Maternity Hospital (OMH) in Sudan to assess the mortality and morbidity among the pre-eclampsia mothers admitted for delivery and among the babies delivered to them Material and methods: It was a prospective cross sectional hospital based study conducted at Omdurman Maternity Hospital (OMH) in Sudan. All the pregnant women with preeclampsia who delivered during June – December 2020 in the hospital were the study population. Sample size was calculated by using this equation, N = Z2X P (1-P)\ e2, Where N = Sample Size. Z = Value 1.96., P = Prevalence. Total 97 women meeting the inclusion criteria was the sample size. Systematic sampling method was applied to collect the files of women admitted in preeclampsia ward. Data were retrieved from the files of the patients which consisted of sociodemographic information, medical and obstetric history, family history, factors associated with preeclampsia and the outcome of the treatment, maternal and prenatal morbidity and mortality. The data were entered and analyzed by using SPSS, version 21 .Descriptive statistics were presented using counts, proportions (%), and mean ± standard deviation whenever appropriate. The comparison study was done by using chi square. A p-value cut off point of 0.05 at 95% CI was used to determine statistical significance. Results: The data from the files of 97 patients with preeclampsia were retrieved for the analysis. Majority of them were in the age group of 20 years or less Almost fifty percent (N=48) were nulliparous while 20.6 %( N=20) were having 2 children, 12.4% having three children and 17.5% had 4 and more children. The gestational age of majority of the patients (64.9%) attending the hospital was between 36-38 weeks. Only 19.6% of the patients were having past history of pre-eclampsia. Ninety nine percent of the patients did not have the family history of preeclampsia. Thirty seven percent of the patients were suffering from severe hypertension at admission while thirty eight percent were suffering from moderate hypertension and only 24.7% were suffering from mild hypertension. The blood pressure at the time of delivery was recorded as normal among the 9.30% of the patients, while mild among 26.80% moderately high among 29.9% and very high among 33% of the patients. As far as the investigations are concerned the vast majority of the patients (96.9%) had 1+ to 3+ protein Urea while 3.1% were having more than 3+ protein Urea in the urine. The majority of the pregnant women (59.8%) had blood hemoglobin level higher than 11 gm. /dl while 35.1% had between 9-11 mg/dl and only 4.1% with blood hg level less than 9gm/dl. Most of the patients (84.5%) underwent caesarian section for delivery. Almost eighty nine percent of the mothers totally recovered after delivery while 9.3% suffered temporal disability and 2.1% by permanent disability. As far as the infant outcome is concerned 68% were born on term while 18.6% as preterm, 8.2% IUFD and 5.2% as term +A life. Thirty three percent of the baby born was of normal weight while majority of them (64.90%) were underweight and only 2.10% were overweight. Conclusion: As far as mortality and morbidity among the mothers and the newborn baby is concerned, though no mortality was reported among the baby and the mothers. Morbidity such as IUFD and low birth weight were reported among babies while majority of the patients with pre-eclampsia underwent caesarian section for delivery and very few mothers suffered from temporal and permanent disability. However the more investment must be made in women’s health needs to reduce the problem and health service providers need to give due attention to high-risk women.

Elevated blood mercury and haematological response in free ranging chicken (Gallus Gallus domesticus) from gold mining areas in Zamfara State Nigeria

Gold mining and other anthropometric activities in mining areas result in pollution. Mercury toxicosis is thus a common occurrence in chickens from gold mining areas (GMAs). The study was designed to evaluate and compare haematological response in chickens (Gallus Gallus domesticus) from Anka GMAs and Gusau Non‑gold mining areas (NGMAs) of Zamfara State, Nigeria. A total of sixty adult chickens were randomly selected in six locations (thirty each in GMAs and NGMAs). Blood mercury concentration was measured with atomic absorption spectrophotometer (AAS) with thermal decomposition. Haematological parameters which include packed cell volume (PCV), Red blood cell count (RBC), haemoglobin, heterophils, lymphocytes, total white blood cell count (TWBC), monocytes and heterophil/lymphocyte (H/L) ratio were measured using standard procedure. Both multivariate and univariate analysis were used to measure differences while correlation and regression were also used to analyse relationship between mercury and haematological parameters. Mean PCV 23.26%, RBC 2.661 × 106/L, Haemoglobin 13.70 g/dL, TWBC 5.07 × 10 9/L, Heterophils 2.00 × 109/L and Lymphocytes 2.65 × 109/L were significantly lower (p < 0.05) in chickens from GMAs when compared with 33.39%, 3.77 × 10 6/L, 19.79 g/dL, 10.13 × 109/L, 2.82 × 109/L and 4.91 × 109/L respectively from NGMAs. However, monocytes 0.44 × 109/L and H/L Ratio 0.788 were significantly higher in chicken from GMAs when compared with 0.24 × 109/L and 0.54 from NMGAs. Hameatological parameters are direct correlates of mercury concentration. A unit increase in monocytes significantly (p < 0.05) correspond to an increase in blood Hg level by 0.262 μg/mL. In conclusion, this research suggested that mining activities in GMAs exerts deleterious impacts on chicken haematological parameters. Result of this study will be of diagnostic significance in local chicken mercury toxicosis.

Selenium and Redox Enzyme Activity in Pregnant Women Exposed to Methylmercury.

Selenium (Se) is a micronutrient with essential physiological functions achieved through the production of selenoproteins. Adequate Se intake has health benefits and reduces mercury (Hg) toxicity, which is important due to its neurotoxicity. This study determined the Se status and redox enzyme, including selenoproteins', activity in pregnant women highly exposed to Hg (between 1 to 54 µg Hg/L blood) via fish consumption. A cross-sectional study enrolling 513 women between the first and third trimester of pregnancy from Madeira, Portugal was conducted, encompassing collection of blood and plasma samples. Samples were analyzed for total Se and Hg levels in whole blood and plasma, and plasma activity of redox-active proteins, such as glutathione peroxidase (GPx), thioredoxin reductase (TrxR) and thioredoxin (Trx). Enzyme activities were related to Se and Hg levels in blood. Se levels in whole blood (65.0 ± 13.1 µg/L) indicated this population had a sub-optimal Se status, which translated to low plasma GPx activity (69.7 ± 28.4 U/L). The activity of TrxR (12.3 ± 5.60 ng/mL) was not affected by the low Se levels. On the other hand, the decrease in Trx activity with an increase in Hg might be a good indicator to prevent fetal susceptibility.

Effects of mercury exposure on fetal body burden and its association with infant growth

Several studies have been conducted among South Korean to investigate effects of high blood mercury (Hg) levels. In this study fetal body burden of Hg in 344 pregnant women were estimated using a physiologically-based pharmacokinetic model (PBPK) and its associative effects on the growth of infants were analyzed. The association between cord blood Hg and growth variables at birth was analyzed based on parameters such as the sex of the newborn, living area, maternal age group, gestation day, maternal body mass index . We investigated the effects of Hg on infant growth through follow-ups, using a non-linear mixed model. The mean Hg levels in maternal and cord blood were 4.47 μg/L and 7.35 μg/L, respectively. Among the subjects, the corresponding fetal body burden for Methylmercury ranged between 26.3-86.9 mg. Cord blood Hg levels positively correlated with length at birth. Furthermore, the high cord blood group showed greater growth rates compared to the low cord blood group. Therefore, we suggest that pregnant women should make efforts to mitigate exposures to Hg, specifically from diet. Further research is suggested to investigate the relationship between the follow-up growth of the infants and Hg levels, considering fish consumption, diet information, and other environmental pollutants.

Environmental Exposure to Metals, Parameters of Oxidative Stress in Blood and Prostate Cancer: Results from Two Cohorts.

We studied the potential role of exposure to various metal(oid)s (As, Cd, Cr, Hg, Ni, and Pb) in prostate cancer. Two cohorts were established: the Croatian cohort, consisting of 62 cases and 30 controls, and the Serbian cohort, consisting of 41 cases and 61 controls. Blood/serum samples were collected. Levels of investigated metal(oid)s, various parameters of oxidative stress, and prostate-specific antigen (PSA) were determined in collected samples. A comparison of the measured parameters between 103 prostate cancer patients and 91 control men from both Croatian and Serbian cohorts showed significantly higher blood Hg, SOD, and GPx levels and significantly lower serum SH levels in prostate cancer patients than in controls. Correlation analyses revealed the significant relationship between certain parameters of oxidative stress and the concentrations of the measured metal(loid)s, pointing to the possible role of metal(oid)-induced oxidative stress imbalance. Furthermore, a significant inverse relationship was found between the blood Pb and the serum PSA in prostate cancer patients, but when the model was adjusted for the impacts of remaining parameters, no significant association between the serum PSA and the measured parameters was found. The results of the overall study indicate a substantial contribution of the measured metal(loid)s to the imbalance of the oxidant/antioxidant system. Although somewhat conflicting, the results of the present study point to the possible role of investigated metal(oid)s in prostate cancer, especially for Hg, since the obtained relationship was observed for both cohorts, followed by the disturbances in oxidative stress status, which were found to be correlated with Hg levels. Nevertheless, further studies in larger cohorts are warranted to explain and confirm the obtained results.

Impact of prenatal exposure to mercury and selenium on neurodevelopmental delay in children in the Japan environment and Children's study using the ASQ-3 questionnaire: A prospective birth cohort.

Neurodevelopmental delay is associated with neurodevelopmental disorders. Prenatal metal exposure can potentially cause neurodevelopmental delays in children. This study examines whether prenatal exposure to mercury (Hg) and selenium (Se) is associated with the risk of neurodevelopmental delays in children up to 4years of age. Children enrolled in a prospective birth cohort of the Japan Environment and Children's Study were examined. Hg and Se levels in maternal (nchild=48,731) and cord (nchild=3,083) blood were analyzed by inductively coupled plasma-mass spectrometry. Neurodevelopmental delays were assessed in children between the ages of 0.5 to 4years using the Ages and Stages Questionnaires, Third Edition. The association between exposure and outcomes was examined using the generalized estimation equation models. In maternal blood, compared to participants with Se levels in the first quartile (83.0 to<156ng/g), the odds ratio (95% confidence intervals) for problem-solving ability in children of mothers in the third (168 to<181ng/g) and fourth quartiles (181 to 976ng/g) were 1.08 (1.01 to 1.14) and 1.10 (1.04 to 1.17), respectively. Furthermore, communication, gross and fine motor skills, and problem-solving delays were also observed. However, prenatal Hg levels in maternal and cord blood and Se levels in the latter were not associated with neurodevelopmental delays in children. Thus, the findings of this study suggest an association between Se levels in maternal blood and slightly increased risks of neurodevelopmental delays in children up to the age of 4years.

Prenatal Exposure to Mercury and Adverse Birth Outcomes in Rio de Janeiro, Brazil: Rio Birth Cohort Study (PIPA Project)

Background: Mercury (Hg) is a highly toxic environmental pollutant, with studies of its prenatal exposure indicating adverse birth outcomes such as low birth weight, preterm delivery, and micro- cephaly. Therefore, we analyzed prenatal Hg exposure levels and their relationship with birth outcomes in pregnant women living in an urban area in the city of Rio de Janeiro. Subjects and Method: A cross-sectional study nested in the prospective birth cohort (PIPA Project) was conducted at the Federal University of Rio de Janeiro Maternity School from October to November 2017. A total of 117 mother-infant pairs were evaluated. The sampling technique used convenience sampling. The independent variables encompassed maternal and cord blood Hg levels, while the dependent variables were birth weight, birth length, head circumference (neonatal anthropometrics), and Apgar score at 1 and 5 minutes. The Hg levels were analyzed using induc- tively coupled plasma-mass spectrometry, and dependent variable data were obtained through medical records. Multiple regression models were applied using the SPSS. Results: The detection rate of maternal and cord blood was 100%, with medians of 0.76 and 0.91 µg/L, respectively. A strong correlation between maternal and cord blood Hg levels was observed (r= 0.70; p&lt;0.010), as well as an inverse association between cord blood Hg and Apgar score at 1 and 5 minutes (b=−0.47; p&lt;0.010; b=−0.34; p&lt;0.010) after adjusting for covariates. Conclusion: Our study provided preliminary evidence that Hg exposure was associated with a worse Apgar score at 1 and 5 minutes. However, the relevance of this finding requires further evaluations due to its potential clinical implications concerning newborn health. Keywords: Mercury, Maternal exposure, Apgar Score, Anthropometry Correspondence: Angelica dos Santos Vianna. Federal University of Rio de Janeiro (UFRJ). Avenida Horacio Macedo sem numero – Proximo a Prefeitura Universitária da UFRJ. Ilha do Fundao – Cidade Universitária. ZIP Code: 21941-598, Rio de Janeiro, RJ, Brazil. Email address: angelica- @iesc.ufrj.br

Exposure to multiple toxic metals and polycystic ovary syndrome risk: Endocrine disrupting effect from As, Pb and Ba

BackgroundPolycystic ovarian syndrome (PCOS) affects 5 % ~ 20 % of women of reproductive age and is a serious health problem. Whether exposure to lead (Pb), mercury (Hg), arsenic (As), barium (Ba) or (cadmium) Cd is associated with an increased risk of PCOS, particularly their joint effect as well as their association with the clinical phenotype of PCOS is limited and unclear. ObjectivesWe aimed to explore the associations of the blood Pb, Hg, As, Ba and Cd levels and risk of PCOS in Chinese women of reproductive age. MethodsA case–control study was used and included 369 women with PCOS and 441 controls. The levels of Pb, Hg, As, Ba and Cd were measured in fasting blood samples collected on the 2nd or 3rd day of menstruation or vaginal bleeding after drug withdrawal; basal sex hormone levels, fasting glucose and fasting insulin were measured simultaneously. Unconditional logistic regression models were used to assess the relationship of the blood Pb, Hg, As, Ba or Cd levels with PCOS risk. Bayesian kernel machine regression (BKMR) was used to assess the joint effect of Pb, Hg, As, Ba and Cd on PCOS risk and estimate which metal or metals contributed most to the association. Multiple linear regression models were used to investigate the relationships between the levels of selected metals and parameters of the clinical PCOS phenotype. ResultsThe mean ± SD ages of women in the case and control groups were 28.80 ± 3.39 and 28.97 ± 2.39 years, respectively; their mean ± SD BMIs were 23.86 ± 3.51 kg/m2 and 22.08 ± 3.14 kg/m2, respectively. The blood levels of three metals (Pb, As and Ba) were statistically associated with PCOS risk based on single-metal models. With each natural logarithm transformed (ln) unit increase in blood concentrations of Pb, higher likelihood of PCOS can be found, the adjusted odd ratio (aOR) and 95 % confidence interval (CI) was 1.83 (1.35–2.48), and these for As and Ba were 2.49 (1.86–3.33) and 1.20 (1.04–1.39), respectively. Compared with women at the first tertile group, higher likelihoods of PCOS among women in the second and third tertiles of the Pb group were observed, aORs and 95 % CIs were 1.81 (1.22–2.68) and 2.08 (1.42–3.04), respectively; and higher likelihoods of PCOS among women in the third tertiles of As and Ba group were also observed, the aORs and 95%CIs were 2.83 (1.93–4.15) and 1.89 (1.32–2.72), respectively. BKMR analysis also showed a statistically significant and positive joint effect of five metals on PCOS risk when the blood levels of five metals were all above the 55th percentile compared with their median levels, and As (100 %) and Pb (67.44 %) were the major contributors to the association. The blood As levels were positively associated with the luteinizing hormone (LH) levels and LH/FSH (follicle–stimulating hormone) ratio values, the blood Ba levels were negatively associated with the FSH levels, and the blood Pb levels were positively associated with the fasting insulin levels and homeostasis model assessment of insulin resistance (HOMA–IR) values. ConclusionsOur results suggest a positive association between exposure to multiple toxic metals (Pb, Hg, As, Ba and Cd) and PCOS risk. As and Pb were the major contributors, evaluated either as a single agent or metal mixture; and Pb, As, and Ba were associated with different parameters of the clinical PCOS phenotype. Additional studies are warranted to confirm these associations, particularly regarding the synergistic effect of toxic metals.

Total arsenic, dimethylarsinic acid, lead, cadmium, total mercury, methylmercury and hypertension among Asian populations in the United States: NHANES 2011–2018

BackgroundNon-Hispanic Asians (NHA) in USA have been reported with higher arsenic (As), lead (Pb), cadmium (Cd), mercury (Hg) and their specific species levels, comparing with non-NHA. This study aimed to investigate the associations of these metal/metalloid levels with blood pressure levels and prevalence of hypertension among general NHA using the 2011–2018 National Health and Nutrition and Examination Survey (NHANES) data. MethodsThe study included participants aged 20 years and older with determinations of As, Dimethylarsinic acid (DMA), Pb, Cd, Hg and methyl-Hg (MeHg) in blood (n = 10, 177) and urine (n = 5, 175). These metals/metalloid levels were measured by inductively coupled plasma mass spectrometry. Systolic (SBP) and diastolic blood pressure (DBP) levels were examined through a standardized protocol. Censored normal regression model and logistic regression model were employed to explore the associations of As, DMA, Pb, Cd, Hg and MeHg levels with blood pressure levels and prevalence of hypertension respectively, and potential confounders were adjusted in these regression models. Quantile-based g-computation approach was used to analysis joint effect of metals mixture on blood pressure level and hypertension. ResultsFor NHA, urinary As and Hg levels were associated with increased DBP level; Higher blood Hg and MeHg levels were related to increased blood pressure levels and hypertension; However, negative association was observed between urinary Cd and SBP level; Blood metals mixture (including blood Pb, Cd and Hg) was associated with increased DBP level, but not for hypertension. For non-NHA, urinary As and DMA levels were associated with increased SBP level, but not DBP level and prevalence of hypertension; Urinary Pb level was associated with decreased DBP level; Nevertheless, positive associations were observed between blood Pb levels and SBP and prevalence of hypertension; Blood Hg level was associated with decreased DBP level and prevalence of hypertension; Furthermore, blood MeHg level was associated with decreased DBP level; Positive association was observed between blood metals mixture and increased SBP level among non-NHA. ConclusionsHighly exposed to Hg level among NHA was associated with increased blood pressure levels and prevalence of hypertension. Urinary As level was associated with increased DBP level among NHA. Furthermore, blood metals mixture was related to increased DBP level among NHA. Further prospective studies with larger sample size should be performed to warrant the results.

Effects of chemical mixtures on liver function biomarkers in the Korean adult population: thresholds and molecular mechanisms for non-alcoholic fatty liver disease involved.

There is a scarcity of research on the effects of a mixture of chemicals on liver function biomarkers and non-alcoholic fatty liver disease (NAFLD) indices, including FSI, HIS, and FBI-4. Thus, we aimed to explore whether there is an association between chemical mixtures, including 26 chemicals found in blood and urine, liver function biomarkers, and non-alcoholic fatty liver disease (NAFLD) indices in Korean adults. The effects of exposure to chemical mixtures on liver function biomarkers and NAFLD indices were investigated using linear regression models, weighted quantile sum (WQS) regression, quantile g-computation (qgcomp), and Bayesian kernel machine regression (BKMR) among 3669 adults. In silico toxicogenomic data-mining, we evaluated molecular mechanisms associated with NAFLD, including pathways, diseases, genes, miRNAs, and biological processes. The linear regression models showed blood or urine Hg levels were the most important factors associated with AST, ALT, GGT, FSI, and HSI levels, and significant trends were observed for these chemical quartiles (p < 0.01). The WQS index was significantly associated with ALT, GGT, FSI, and HSI. The qgcomp index also found an association between chemicals and AST, ALT, GGT, and FSI. In the BKMR model, the overall effect of the mixture was significantly related to ALT, GGT, FSI, and HSI. In silico analysis, we found mixed chemicals interacted with the CYP1A2 gene and were associated with NAFLD. Seventy-eight percent of interactions were identified as physical interactions in the CYP1A2 gene related to NAFLD. Transcription factor regulation in adipogenesis and lipid metabolic processes are fundamental molecular mechanisms that could be influenced by NAFLD-related mixed chemicals. Cutoff thresholds for chemical exposure levels associated with liver function indicators and NAFLD indices were also reported. The strongest interactions and expression of miRNAs involved in NAFLD development were also identified.

Associations of maternal blood mercury with preeclampsia and birth outcomes

Background: Mercury (Hg) is a highly toxic substance, and its harmful effects on maternal and infant health have been reported. Yet, the associations of Hg exposure with preeclampsia (PE) and adverse birth outcomes are not well understood. Objective: The aim of this study was to investigate the potential effects of maternal Hg exposure on PE and birth outcomes. Methods: We conducted a case-control study with 84 participants in China. Logistic models were used to estimate odds ratios for PE risk and birth outcomes according to maternal blood Hg levels, adjusting for potential confounding factors. Results: Elevated blood Hg levels were associated with increased risks of mild PE (aOR, 7.03; 95% CI, 1.61, 30.62; P < 0.01) and severe PE (aOR, 47.55; 95% CI, 5.27, 429.05; P < 0.05). We also found that increased blood Hg levels were associated with low birth weight (aOR, 1.12; 95% CI, 1.00, 1.25; P < 0.05) and preterm birth (PTB) (aOR, 1.22; 95% CI, 1.08, 1.38; P < 0.05). Conclusions: Our study provided evidence that elevated blood Hg levels were significantly associated with an increased risk of PE. In addition, our findings support that increased blood Hg levels might be associated with low birth weight and PTB.