Blood Mercury Levels Research Articles

Assessment of Lead and Mercury Exposure Levels in the General Population of Korea Using Integrated National Biomonitoring Data.

In Korea, the estimated values of blood lead (Pb) and mercury (Hg) levels differ between two national-level biomonitors, namely the Korean National Environmental Health Survey and the Korea National Health and Nutrition Examination Survey. The present study used integrated data from these surveys to estimate the representative values of the change in concentration and recent distribution characteristics. The yearly trend of age-standardized exposure levels in regular adults was identified, and the geometric mean (GM) adjusted according to demographic characteristics was presented. Age-standardized GM for blood Pb and Hg in the integrated data was 2.06 and 3.64 μg/L in 2008, respectively, which decreased to 1.55 and 2.92 μg/L, respectively, by 2017. Adjusted GMs from most recently conducted surveys (2015–2017) were 1.61 and 2.98 μg/L for blood Pb and Hg, respectively. In particular, the adjusted percentage of blood Hg exceeding the reference value of 5 μg/L was 20.79%. While the blood Pb and Hg exposure levels are decreasing in Korea, the levels remain high relative to those in other countries. The Hg levels exceeded the reference value in many individuals. Therefore, continued biomonitoring must be conducted, and a reduction plan and exposure management are needed for harmful metals, including Hg.

Association between Blood Mercury Levels and Non-Alcoholic Fatty Liver Disease in Non-Obese Populations: The Korean National Environmental Health Survey (KoNEHS) 2012-2014.

Mercury is widely distributed in the environment, and a plausible association between mercury exposure and hepatic damage has been reported. Non-alcoholic fatty liver disease (NAFLD), which comprises a spectrum of liver diseases, has recently been recognized in non-obese subjects. However, there have been no studies on the relationship between internal mercury levels and NAFLD in non-obese individuals. Therefore, we investigated the association between blood mercury levels and NAFLD in non-obese subjects. Cross-sectional data (n = 5919) were obtained from the Korean National Environmental Health Survey (2012–2014). NAFLD was defined using the hepatic steatosis index (HSI). Blood mercury levels were log-transformed and divided into quartiles based on a weighted sample distribution. The association between blood mercury levels and NAFLD was analyzed using a multivariate logistic analysis after body mass index stratification. The geometric mean of blood mercury in the overweight group was significantly higher than that of the non-obese group (p < 0.001). The weighted frequencies of patients with NAFLD based on the HSI were 3.0–7.2% for the non-obese subjects and 52.3–63.2% for the overweight subjects. In the multivariate analysis, blood mercury levels were positively associated with NAFLD for both the overweight and non-obese groups (all p for trend < 0.001). Increased blood mercury levels are closely associated with NAFLD. In particular, mercury could be a risk factor for NAFLD in the non-obese population.

MO894EVALUATIONS OF TOXIC HEAVY METALS LEAD AND MERCURY IN REGULAR HEMODIALYSIS SMOKER AND NONSMOKER PATIENTS BY COMPARISON WITH OTHER HEALTHY CONTROL SUBJECTS IN EGYPTIAN POPULATION

Abstract Background and Aims Around worldwide population, 10% are affected by chronic kidney diseases (CKD); hemodialysis is the common choice of renal replacement therapy. Cigarette smokers have higher Lead level than non-smoker population. As Tobacco leaves are grown on polluted soil, it is proven that Mercury poisoning depends on dose and duration of exposure. Aim of the study was to determine two important toxic heavy metals elements Lead and Mercury concentrations in regular hemodialysis patients smoker and non-smoker by comparison with normal subjects and its correlation to anemia. Method Blood samples were collected from CKD patients on maintenance hemodialysis for more than 6 months divided into non-smoker and smoker to be compared with samples from a control group of non-CKD, non-smoker persons. This study was conducted in September 2019 in Al Mokattam Insurance Hospital – Cairo and involved 60 persons of both sex. They were divided into 3 groups: CKD stage 5 patients on hemodialysis 40 patients and sub-divided into 2 groups; (smoker) 20 patients and (non-smoker) 20 patients and the history of eating fish and seafood was taken. The third group was a control group included 20 healthy non-smoker participants. Lead and Mercury were analyzed by electro thermal atomic absorption spectrophotometer in Al Borg central Laboratory. The complete blood count (CBC), kidney function tests and Iron parameters were also detected. Results duration on hemodialysis did not raise Lead or Mercury level in blood, while smoking raises Lead level in blood, and eating fish and sea food more than once per week increased Mercury level in blood. There was a relation between raised Lead level and anaemia in hemodialysis patients. Conclusion Lead Prolonged and Mercury measurement is important in hemodialysis patients with possible symptoms of heavy metal toxicity. Lead level monitoring is recommended in resistant anemia in hemodialysis patients.

Estimation of mercury levels in blood by GFAAS after administration of two variants of Shwasakuthara Rasa in human volunteers

Introduction: Mercury is in use as medicine since thousands of years in India. It is the most important raw material of medicines belonging to Rasashastra, a branch of Ayurveda. It is need of time to establish data of pharmacokinetics of mercurial medicines. This is a preliminary study to know the absorption of Shwakakuthara Rasa, a herbo-mineral formulation. Aim: The study drug viz Shwasakuthara Rasa is a complex triturated drug having herbal and mineral ingredients. In this study, bioavailability of mercury from two samples Shwaskuthar Rasa was assessed. Materials and Methods: Shwaskuthar Rasa samples [S 1 and S 2] were manufactured by two formulas from Ayurvedic literature. Ingredients of the formulation are detoxified mercury, detoxified sulfur, detoxified realgar, detoxified borax, detoxified Aconitum ferox Piper nigrum, Piper longum, and Zingiber officinalis. Detoxification of said ingredients was done by specific processes mentioned in Ayurvedic literature. Per cent amount of detoxified mercury is 7.14 % and 11.1 % in S1 and S2 respectively and amount of Piper nigrum is 60% and 22.2 %, respectively. After administration of 125 mg dose of the S1 and S2 to 8 normal volunteers, blood samples were collected at 0, 1, 1.5 and 2 hours. The blood mercury levels were assessed by Graphite Furnace Atomic Absorption Spectroscopy (GFAAS). Results: It is evident that mercury gets absorbed from both formulations. There is difference in absorption pattern. After 2 hours of administration of formulation; mercury level in blood from S1 is significantly higher than S2. Conclusions: The increased absorbance of mercury from S1 can be attributed to much higher levels of P. nigrum in it than S2. Keywords: Ayurveda, Rasashastra, Parad mercury, Shwasakuthara Rasa, Bioavailability, Pharmacokinetics.

Toxic Metals and Non-Communicable Diseases in HIV Population: A Systematic Review.

Background and Objectives: HIV has been a serious global health concern since its discovery, with about 37.9 million people living with HIV worldwide as of 2018. Sub-Saharan Africa (SSA) accounts for 68% of the infection and contributed 74% of the 1.5 million deaths in 2013 despite having only 12% of the total world population residing in the region. This systematic review has attempted to determine the association between heavy metal toxicity and the occurrence of non-communicable diseases in the HIV/AIDS population. Materials and Methods: Three databases were systematically searched: PubMed, Scopus, and Google Scholar for studies written in English and published between 1 April 2000 and 12 April 2020. Studies were excluded if the main outcomes were not measured or did not meet the inclusion criteria. Results: All the six included studies are cross-sectional in design, and therefore were evaluated using the STROBE checklist. The data extraction was done using an extraction table; the ratio of female to male participants included in the study was 1.09:1. Qualitative analysis was used due to the heterogeneity in the heavy metal biomarkers and the outcome measured by the included studies. Two studies compared the concentration of heavy metals in HIV-positive and HIV-negative participants while one compared the levels between HAART-naïve and HAART-treated participants, and three determined the association between heavy metal toxicity and non-communicable diseases (liver fibrosis, anaemia, and reproductive parameters, respectively) in HIV-positive patients. Conclusions: Blood lead, cadmium, and mercury levels were higher in HIV-seropositive than -seronegative subjects, whereas serum zinc level was lower in HIV-seropositive than -seronegative subjects, but the causal association between heavy metals and non-communicable diseases in HIV subjects is largely unknown. Interdisciplinary research between nutrition, toxicology, and human health is envisaged for primary and secondary prevention and treatment.

Risk factors and early renal effects of environmental exposure to the trace elements in Moroccan adolescents.

In Morocco, the use of leaded-gasoline is still common even after its ban in 2011, and other sources of contamination by traces elements are not regulated. We aimed to assess blood and urinary cadmium, blood lead, and total blood mercury levels in Moroccan adolescents and to identify determinants and early renal effects of exposure. The study included 149 school adolescents (12 to 18 years), from urban, industrial, and rural areas in Fez city (north of Morocco). Risk factors were investigated by interviews and questionnaires. Internal doses and early renal effects were evaluated by analyzing blood and urinary samples. The mean of blood lead levels (BLLs) in all adolescents was 47.81μg/l with no difference between boys and girls. Adolescents from the urban area had the highest BLLs mean. The means of blood cadmium levels (BCLs) and urinary cadmium levels (UCLs) were 0.29μg/l and 0.45μg/l respectively, with no differences between living areas or according to sex. The total blood mercury levels (BMLs) mean was 0.52 μg/l. BMLs mean was higher in the industrial area and among boys. This can be associated to the frequency of fish intake, the use of dental amalgams fillings, and the consumption of chewing gum. Rates of early renal effects markers were low, not correlated to the metals, and may indicate that renal effects of this environmental exposure could be limited. There is an urgent need for the limitation of trace elements' sources, particularly the strict application of the laws concerning leaded-petrol prohibition.

Association between urinary arsenic, blood cadmium, blood lead, and blood mercury levels and serum prostate-specific antigen in a population-based cohort of men in the United States.

Exposures to heavy metals have been linked to prostate cancer risk. The relationship of these exposures with serum prostate-specific antigen (PSA), a marker used for prostate cancer screening, is unknown. We examined whether total urinary arsenic, urinary dimethylarsonic acid, blood cadmium, blood lead, and total blood mercury levels are associated with elevated PSA among presumably healthy U.S. men. Prostate cancer-free men, aged ≥40 years, were identified from the 2003–2010 National Health and Nutrition Examination Survey. Logistic regression analyses with survey sample weights were used to examine the association between heavy metal levels and elevated PSA for the total population and stratified by black and white race, after adjusting for confounders. There were 5,477 men included. Approximately 7% had elevated PSA. Men with an elevated PSA had statistically significantly higher levels of blood cadmium and blood lead compared to men with a normal PSA (p-values ≤ 0.02), with black men having higher levels. After adjusting for age, race/ethnicity, body mass index, smoking, and education, there was no association found between any of the heavy metal levels and elevated PSA for the total population. In addition, there was no association found when stratified by black and white race. Further investigation is warranted in a larger cohort of men who persistently are exposed to these heavy metals.

Pre and postnatal exposure to mercury and respiratory health in preschool children from the Spanish INMA Birth Cohort Study

Effects of mercury on maturing immune system have been reported, however the association with respiratory and allergy problems during infancy remains unclear. The aim of this study is to evaluate the association between pre and postnatal mercury exposure and respiratory and allergy problems among preschool children and to examine the role of potential modifying factors. Study subjects were children participant in Spanish Childhood and Environment Project (INMA, 2003–2008). We measured total mercury levels in cord blood (n = 1868) and hair at 4 years of age (n = 1347). Respiratory outcomes (wheezing, severe wheezing, chestiness, persistent cough, eczema and otitis) were obtained by questionnaires administered to parents. Associations were investigated by logistic regression adjusted for socio-demographic and lifestyle-related variables in each cohort and subsequent meta-analysis. We tested effect modification by factors related to individual susceptibility, diet and co-exposure with other pollutants. The geometric mean of cord blood and hair total mercury was 8.20 μg/L and 0.97 μg/g, respectively. No statistically significant association between pre or postnatal mercury exposure and respiratory and allergy outcomes was found. Notwithstanding, lower maternal intake of fruits and vegetables increased the risk of some respiratory outcomes due to the prenatal exposure to mercury (pint < 0.05). Moreover, an inverse association between prenatal mercury exposure and some respiratory outcomes was observed among children with higher maternal exposure to organocholorine compounds or smoking (pint < 0.05). Also, sex and postnatal smoking exposure modulated mercury postnatal effects on persistent cough (pint < 0.05). In conclusion, no association between pre and postnatal mercury exposure and respiratory and allergy problems among the whole population at study was found. However, diet and other toxicants could modulate this relation, especially during prenatal period. More research on this topic is warranted due to the limited evidence.

Blood lead and mercury levels are associated with low resting heart rate in community adolescent boys.

While the neurotoxic effects of heavy metals at even low levels have been well-studied, few studies have examined the cardiovascular effects of heavy metals on resting heart rate and these have focused on adult populations. The present study aimed to examine the association between low-level environmental lead and mercury exposure and resting heart rate in community adolescents. As part of the China Jintan Cohort Study, 532 adolescents aged 12 years (SD=0.6) were tested for blood levels of lead (BLL) and mercury (BML) and resting heart rate (RHR). Generalized linear models were conducted to test the relationship between BLL and BML and RHR, controlling for children's sex, age, and socioeconomic status. Analyses were clustered at the preschool level when the children were recruited to adjust for standard error. The mean (SD) BLL and BML were 3.14 (SD=1.19) μg/dL and 1.26 (SD=0.68) μg/L at age 12 years, respectively. After adjusting for confounders, we found a significant interaction between BML and BLL in predicting RHR in boys (B=-1.27, SE=0.49, p<0.01, n=289). We created BLL and BML groups in boys based on median cut-offs. Boys in the High BLL/High BML group had significantly lower RHR (mean=84.22 beats per minute [bpm], SD=8.77, n=61) than boys in the Low BLL/Low BML group (mean=89.03 bpm, SD=10.75, n=69; p<0.05). BML and BLL did not interact to predict RHR in girls (B=-0.18, SE=0.88, p>0.05, n=242). Combined high BLL and BML were associated with low RHR in community adolescent boys. Low RHR is an indication of chronic under-arousal and has been implicated in psychopathology, particularly for externalizing behavior. Our findings may stimulate further communication and research in this area.

Association of lead, mercury, and cadmium with metabolic syndrome of young adults in South Korea: The Korea National Health and Nutrition Examination Survey (KNHANES) 2016.

This study examines the relations between blood lead, mercury, and cadmium levels, affect metabolic syndrome of young adults. This study is a descriptive study on verifying the relation between blood lead, mercury, cadmium level, and subcategories of metabolic syndrome. A total of 823 respondents' data of 19~29years were sampled of the Korea National Health and Nutrition Examination Survey 2016 conducted under the National Health Promotion Law. To identify the predictive risk factors of metabolic syndromes, the subcategories of metabolic syndromes and the lead, mercury, and cadmium levels were analyzed using logistic regression. Pearson's correlation was used to identify correlations among the factors. An analysis of the correlations among the metabolic syndromes and blood levels of lead, mercury, and cadmium showed significant relationships between blood lead level and systolic pressure, diastolic pressure, waist circumference, and triglyceride level; also between blood mercury level and waist measurement and triglyceride level; and between blood cadmium level and waist circumference and triglyceride level (p<.05). This study is significant in that it provides basic data on the correlation between metabolic syndromes and heavy metals among young adults.

Comparisons of zero-augmented continuous regression models from a Bayesian perspective.

The two-part model and the Tweedie model are two essential methods to analyze the positive continuous and zero-augmented responses. Compared with other continuous zero-augmented models, the zero-augmented gamma model (ZAG) demonstrates its performance on the mass zeros data. In this article, we compare the Bayesian model for continuous data of excess zeros by considering the ZAG and Tweedie model. We model the mean of both models in a logarithmic scale and the probability of zero within the zero-augmented model in a logit scale. As previous researchers employed different priors in Bayesian settings for the Tweedie model, by conducting a sensitivity analysis, we select the optimal priors for Tweedie model. Furthermore, we present a simulation study to evaluate the performance of two models in the comparison and apply them to a dataset about the daily fish intake and blood mercury levels from National Health and Nutrition Examination Survey. According to the Watanabe-Akaike information criterion and leave-one-out cross-validation criterion, the Tweedie model provides higher predictive accuracy for the positive continuous and zero-augmented data.

Levels of Mercury and Lead in Blood and Hair of Autistic Children in Tripoli

Background There are many published studies related to environmental pollutants Mercury and Lead to autism in children. One of the most environmental factors that have received significant attention is the burden of mercury, lead, and other toxic metals. However there are no studies in Libya about the levels of heavy metals in blood and hair of autistic children. Objectives This study is to investigate and compare the levels of environment pollutants Lead and Mercury in blood and hair of autistic children in Tripoli. Methods Randomly selected autistic children (males=49, females=11), born between 2000 and 2010 with average age 6.2 years old, attending an autism rehabilitation center in Tripoli, consent form had signed with the parents to take blood and hair sample in Bioscientia laboratory in Tripoli in July 2013 then samples were sent to Germany main lab to be tested using atomic absorption spectrophotometry. Results 75 percent of male children had high readings of mercury in blood compared with females whose percentages were 13. Only 8 percent of cases had high lead blood levels. With regard to hair samples, 2 percent of male children showed high mercury levels and 27 percent showed high lead levels; while in female children zero percent had high mercury levels and 3 percent had high lead levels. Conclusion On this study autistic children have shown variable high levels of mercury and lead in their body content that calls for further investigational studies. Key words: environmental pollutants, autism, mercury, lead, heavy metals, blood and hair.

The association of blood mercury levels with interference control in 6 years old children

Background: Human bodies are constantly exposed to heavy metals like mercury due to industrialization and environmental pollution. The health effects of mercury have been a common concern. In particular, children need to be more careful because they are in the stage of growth and development. However, there is no firm consensus about the effects of mercury on neurodevelopment in children. Methods: We describe the association between blood mercury concentrations in 6 years old children (N = 574) and with the Stroop color and word test(SCWT) scores based on the Environment and Development of Children (EDC) study, a prospective cohort study. In the SCWT, the color word score represents the subject's ability to control cognitive interference. Univariate analysis and multivariate analysis consisting of three models were performed with different variables and stratification of gender was also conducted. Results: There was no statistically significant association between the log-transferred prenatal and postnatal blood mercury levels and the ability of interference control in 6 years old children (N = 396). However, when stratified by gender, girl's color-word test score in Model 1 showed a decrement by -3.71 points for each log-transferred blood mercury increment (p-value = 0.0765). This trend persisted in Model2 (Beta: -3.76, p-value = 0.0766) and Model3 (Beta: -4.06, p-value = 0.0547). Conclusions: The result suggests that mercury exposure may affect interference control especially in girls. The color-word score in the SCWT is a score obtained by suppressing the automated reaction to read letters under the condition that the color of word and letter do not match and reflecting the frontal lobe suppression process. The analysis showed that the ability to control cognitive interference may decrease with an increment of log blood mercury concentration.

Identifying Multiple Exposure Burden with National Biomonitoring Data

Background The main impetus for the current assessment and management of hazardous chemicals is on its doses and health effect, but fewer studies have evaluated types of chemical mixtures, number of exposed chemicals and the vulnerable groups in general public. This study investigated exposure load through national biomonitoring program to pursue the exposure complexity over general population and to assess multipollutant exposure burden. Methods We obtained data from the Korean National Environmental Health Survey (2015-2017) and 6,167 participants were recruited including 571 preschoolers(3 to 5), 887 school-aged children(6 to 11) , 922 adolescent(12 to 18) and 3,787 adults(19 and older). All subjects were sampled for urinary levels of mercury, cadmium, polycyclic aromatic hydrocarbon(PAH) metabolites, volatile organic compound(VOC) metabolites, phthalate metabolites, parabens, environmental phenols, pyrethroid metabolite and cotinine. Additionally, blood lead and blood mercury levels were measured for ages 12 and older. In total, 26 chemicals were included in the analysis. We conducted several exposure load calculations with binary values for each individual analyte with different age groups and thresholds(limit of detection(LOD), 50th, 75th ,95th). Results Using LOD as exposure thresholds, 20% of all participants(age 3 to 86) were exposed to more than 25 chemicals. With 50th, 75th ,95th percentile thresholds, 20% of each population were exposed to more than 18, 11 and 2 chemicals, respectively. For participants who had the highest exposure to each chemical(95th percentile) cadmium was the most frequent chemical and 17.2% of all population had more than one heavy metal(mercury, lead, cadmium) exposure. For each age group, the most frequent chemical differed; cadmium for adults, bisphenol F and A for adolescent, monobenzyl phthalate for school-aged children, and 1-hydroxyphenanthrene for preschoolers. Conclusions These results can improve multipollutant exposure burden assessment, especially for the highly susceptible population and can strengthen national chemical management practice.

CONAMAD: Birth cohort to quantify the effects of in-utero metals exposure on child development in an artisanal and small-scale gold mining region of the Amazon

Research quantifying in-utero trace metals exposure and health effects have been conducted primarily in developed regions. Given the global increase of artisanal scale gold mining (ASGM), there is a critical need to quantify in-utero exposure to trace metals and related health risks in populations living in ASGM environments, characterized by high prevalence of malnutrition, infectious disease, and poverty. We describe the design and initial results of CONAMAD, a birth cohort of multiparous women (18 and over) living in an ASGM region of Madre de Dios (MDD), Peru, whose long-term goal is to quantify in-utero toxic metals exposures and subsequent child health effects during the first two years of life. 270 mothers were enrolled during pregnancy across four zones representing differential economic and development activities in MDD. At enrollment, women averaged 28 years of age, 20 weeks gestational age, and 17% were of short stature (&lt;1.45m). Half of all mothers lived near a major road and ~20% lived near mining or a gold shop, which varied by location (p&lt;0.001). We obtained biomarkers from 215 mothers and their newborns at birth, including maternal and cord blood, hair samples, and placenta for exposure assessment. The median levels of mercury and lead in cord blood were 5.8 μg/L and 10.0 μg/L, respectively, while median levels in maternal blood were 3.4 μg/L and 13.3 μg/L, respectively (USEPA BMDL is 5.8 μg/L for blood Hg, 5 μg/dL for lead). USEPA assumes cord:maternal blood mercury ratio (Hgc:Hgm) to be equal when estimating reference doses for risk quantification; however, we find higher median Hgc:Hgm of 1.67 (10th to 90th percentile: 1.13-2.42) with 93% of cord blood Hg samples exceeding maternal blood levels. Results indicate that the developing fetus may have increased health risks if standard public health recommendations are followed by pregnant women in ASGM regions.

Element profiles in blood and teeth samples of children with congenital heart diseases in comparison with healthy ones

BackgroundSome elements were claimed to play a role in the pathogenesis of congenital heart defects (CHD) and influence the general well-being and health of these children. ObjectivesWe aimed to assess the levels of some elements simultaneously in the blood and teeth samples of children with cyanotic and acyanotic CHD compared with healthy children. MethodsA total of 39 children with CHD (11 with cyanotic and 28 with acyanotic CHD) and 42 age- and sex-adjusted controls were enrolled. Levels of 13 elements, including magnesium, phosphorus, calcium, chromium, manganese, iron, copper, zinc, strontium, cadmium, lead, mercury, and molybdenum, were assessed using inductively coupled plasma mass spectrometry. ResultsChildren with cyanotic and acyanotic CHD had significantly lower teeth calcium and calcium/phosphorus ratio as compared to the controls after adjusting for confounders. The mean blood iron level was found to be significantly higher in the cyanotic CHD group compared to the other groups. In addition, children with acyanotic CHD had significantly higher teeth copper levels, higher blood molybdenum and lower blood magnesium levels compared to the healthy control group. Blood cadmium and mercury levels were found to be significantly elevated in both the cyanotic and acyanotic CHD groups compared to the healthy control group. There were no differences in toxic metal levels of teeth in cases with CHD. ConclusionMonitoring adequate and balanced gestational micronutrient intake might support not only maternal health but also fetal cardiac development and infant well-being. Supplementation of magnesium should be evaluated in patients having CHD.

Temporal variation of total mercury levels in the hair of pregnant women from the Maternal-Infant Research on Environmental Chemicals (MIREC) study

Prenatal exposure to total mercury (T-Hg) comes from both natural and anthropogenic sources. T-Hg can cross the blood-brain and placental barriers, and may be associated with future neurological and physiological dysfunctions. Scalp hair is an optimal and non-invasive indicator of chronic T-Hg exposure. As part of the Maternal-Infant Research on Environmental Chemicals (MIREC) Study, hair samples from 350 women were collected within weeks after giving birth, to determine temporal variations in T-Hg levels from preconception to delivery, and to compare these levels to corresponding levels measured in other matrices (maternal and umbilical cord blood, and infant’s meconium). A maximum of 12 one-cm hair segments were cut starting at the scalp; segments closer to the scalp reflected recent exposure (within the last month). For proper comparison, the hair segments were matched with the collection dates for other matrices. GM hair T-Hg levels greatly decreased during pregnancy, from 0.26 μg g−1 (preconception or full-length hair) to 0.18 μg g−1 (at delivery or segments closer to the scalp). A similar decreasing trend was found for T-Hg in maternal blood: 1st trimester (0.60 μg L−1) to 3rd trimester (0.47 μg L−1). The median hair-to-blood ratios of T-Hg levels varied from 364 (1st trimester), to 408 (3rd trimester), to 229 (cord blood). Very low T-Hg levels were detected in meconium. Mercury levels in blood and hair correlated with consumption of large predatory fish.

Sources and Toxicity of Mercury in the San Francisco Bay Area, Spanning California and Beyond.

This report synthesizes and evaluates published scientific literature on the environmental occurrence and biomagnification of mercury with emphasis on the San Francisco Bay Area (SFBA), California. Mercury forms various compounds, well known for their toxicity in humans and environmental ecosystems. Elemental mercury is transported and distributed by air, water, and sediments. Through the metabolic processes of algae and bacteria, mercury is converted into organic compounds, such as methylmercury (MeHg), which then bioaccumulates up through trophic levels. In fish, it is found primarily in skeletal muscle, while in humans, the primary target organs are the brain and kidneys. Health concerns exist regarding bioaccumulation of mercury in humans. This paper reviews the known anthropogenic sources of mercury contamination, including atmospheric deposition through aerial transport from coal burning power plants, cement production, and residual contaminants of mercury from gold mining, as well as mercury-containing waste from silver amalgams emitted from dental offices into waterways. Although tools exist for measuring mercury levels in hair, breast milk, urine, blood, and feces in humans, current diagnostic tools are inadequate in measuring total mercury load, including deposited mercury in tissues. Additionally, insufficient attention is being paid to potential synergistic impacts of mercury interaction with multipliers such as lead, cadmium, and aluminum. We provide specific data on methylmercury concentrations at different trophic levels, followed by recommendations for reducing the level of mercury in the SFBA in order to protect the health of humans and other species.

Link between blood mercury levels and skin cancer in the USA

British Journal of DermatologyVolume 183, Issue 3 p. e76-e76 Plain Language SummaryFree Access Link between blood mercury levels and skin cancer in the USA First published: 02 September 2020 https://doi.org/10.1111/bjd.19362AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat Abstract Non-melanoma skin cancer (NMSC), also known as keratinocyte cancer, includes squamous cell carcinoma and basal cell carcinoma and affects more than 5 million people aged over 65 years in the USA every year. We need to understand more about the causes of skin cancer in order to prevent it. Exposure to mercury is an occupational hazard in the nuclear weapons industry, some chemical plants and dentistry. Workers exposed to mercury are at greater risk of brain and lung cancers than the rest of the population, but little is known about their risk of skin cancer. In addition, few studies have focused on how mercury exposure, mainly from eating fish, affects the general population. Previous studies looked at mercury exposure in terms of occupation but did not look at actual mercury levels in the body. These public health doctors and dermatologists from the USA looked for a link between blood mercury levels and NMSC using data from the National Health and Nutrition Examination Survey (NHANES), which collected health information from a large cross-section of Americans using questionnaires and blood tests. Among 29,413 adults recruited to NHANES from 2003 to 2016, 468 reported having had NMSC. Overall those with higher blood levels of mercury were nearly twice as likely to have NMSC. The results from this study support the possibility of a role for mercury exposure in causing NMSC. Linked Article: Rhee J et al. Br J Dermatol 2020; 183:480–487. Volume183, Issue3September 2020Pages e76-e76 RelatedInformation

Adverse effects of prenatal mercury exposure on neurodevelopment during the first 3 years of life modified by early growth velocity and prenatal maternal folate level

Background and aimsPrevious studies have suggested that mercury exposure and folate levels during pregnancy may influence early childhood neurodevelopment. Rapid catch-up growth in children is associated with an increased risk of pathological nervous system development. We evaluated whether the association between prenatal folate and mercury-related neuropsychological dysfunction was modified by growth velocity during childhood. MethodsThe Mothers and Children's Environmental Health (MOCEH) birth cohort study began in 2006 and by 2010, 1751 women had been enrolled before the second trimester of their pregnancy along with their partners. Participants visited the research center at birth and 6, 12, 24, and 36 months. We measured mercury levels in maternal and cord blood and folate in maternal serum. Questionnaires to evaluate the environment and health of their child were administered and anthropometric factors including body weight and height were measured. Certified investigators used the Bayley test to measure neurobehavioral outcomes. We calculated postnatal growth change as the change in infant weight for-age z-score between birth and 3 years. Multiple linear regression and mixed models were used to examine the association between mercury exposure and children's neurodevelopment as well as the modifying effects of folate and growth velocity. ResultsA total of 30.6% of children experienced rapid growth during the first 3 years of life. Median values of mercury in the low folate group were significantly higher in rapid growers (3.41 μg/L in maternal blood and 5.63 μg/L in cord blood) than in average/slow growers (3.05 μg/L in maternal blood and 5.19 μg/L in cord blood). Rapid growers were also significantly associated with decreased psychomotor development scores during the first 3 years of life and with having mothers who had low prenatal folate levels, even after adjusting for potential confounders. ConclusionPrenatal mercury exposure adversely affects infant neurodevelopment and is associated with rapid growth during the first 3 years of life. This effect was limited to children whose mothers had low prenatal folate levels, suggesting a protective effect of folate against developmental neurotoxicity due to mercury exposure and rapid catch-up growth.