Mercury Levels in Hair of Pregnant Women in Tumbes, Peru: A Cross-Sectional Study.

Mercury, a potent toxin that poses serious risks to human health, particularly for pregnant women and young children, is widely present due to artisanal and small-scale gold mining (ASGM), which impacts water quality. The objective of this study was to evaluate methylmercury exposure among pregnant women in communities downstream from ASGM sites. We characterized hair total mercury (THg) concentrations among 148 pregnant women across 24 communities in the Tumbes region of Peru, downstream from ASGM sites in Ecuador.

Hair mercury isotopes, a noninvasive biomarker for dietary methylmercury exposure and biological uptake.

. Fish and rice are the main dietary sources of methylmercury (MeHg); however, rice does not contain the same beneficial nutrients as fish, and these differences can impact the observed health effects of MeHg. Hence, it is important to validate a biomarker, which can distinguish among dietary MeHg sources.

Associations between urogenital carcinoma and DECA-BDE (BDE-209) among wild California Sea lions (Zalophus californianus) and Steller Sea lions (Eumetopias jubatus).

Urogenital carcinoma (UGC) is prevalent among California sea lions (Zalophus californianus), while less is known concerning UGC among Steller sea lions (Eumetopias jubatus). Our objective was to investigate associations between UGC and polybrominated diphenyl ethers (PBDEs) among both sea lion species. Twenty-nine California sea lions and 20 Steller sea lions were lethally removed from the Columbia River Basin, Oregon, USA between 2020 and 2021, under Section 120 of the Marine Mammal Protection Act.

Distribution and accumulation of mercury in pot-grown African rice cultivars (Oryza glaberrima Steud. and Oryza sativa L.) determined via LA-ICP-MS.

There is limited information concerning the distribution of mercury in rice, particularly in African rice. The objective was to compare the distribution of total mercury (THg) and methylmercury (MeHg) in African rice (Oryza glaberrima Steud.) and Asian rice (O.

Fecal Methylmercury Correlates With Gut Microbiota Taxa in Pacific Walruses ().

Objectives: Methylmercury metabolism was investigated in Pacific walruses () from St. Lawrence Island, Alaska, United States.

Methods: Total mercury and methylmercury concentrations were measured in fecal samples and paired colon samples ( = 16 walruses).

Maternal methylmercury exposure through rice ingestion and child neurodevelopment in the first three years: a prospective cohort study in rural China.

Background: Rice is an important dietary source for methylmercury; however, rice does not contain the same beneficial nutrients as fish. Our main objective was to assess associations of prenatal methylmercury exposure through rice ingestion with child neurodevelopment in rural China.

Methods: Eligible peripartum women were enrolled (n = 391), provided peripartum hair samples, and children's neurodevelopment was assessed at 12 months (n = 264, 68%) and 36 months (n = 190, 48%) using the Bayley Scales of Infant Development, 2nd Edition, including the Mental Developmental Index (MDI) and the Psychomotor Developmental Index (PDI).

Neurodevelopment correlates with gut microbiota in a cross-sectional analysis of children at 3 years of age in rural China.

We investigated cross-sectional associations between children's neurodevelopment and their gut microbiota composition. Study children (36 months of age) lived in rural China (n = 46). Neurodevelopment was assessed using the Bayley Scales of Infant Development, 2nd Edition, yielding the Mental Developmental Index (MDI) and Psychomotor Developmental Index (PDI).

Community Approaches for Integrating Environmental Exposures into Human Models of Disease.

Background: A critical challenge in genomic medicine is identifying the genetic and environmental risk factors for disease. Currently, the available data links a majority of known coding human genes to phenotypes, but the environmental component of human disease is extremely underrepresented in these linked data sets. Without environmental exposure information, our ability to realize precision health is limited, even with the promise of modern genomics.

Sewage spills are a major source of titanium dioxide engineered (nano)-particles into the environment.

Sanitary sewer overflows (SSOs) are a common problem across the United States. An estimated 23,000-75,000 SSOs occurred annually in 2004 discharging between 11 and 38 billion liters of untreated wastewater to receiving waters. SSOs release many contaminants, including engineered nanomaterials (ENMs), to receiving water bodies.

Longitudinal changes during pregnancy in gut microbiota and methylmercury biomarkers, and reversal of microbe-exposure correlations.

Objective: Gut microorganisms contribute to the metabolism of environmental toxicants, including methylmercury (MeHg). Our main objective was to investigate whether associations between biomarkers for prenatal MeHg exposure and maternal gut microbiota differed between early and late gestation.

Methods: Maternal blood and stool samples were collected during early (8.

Enrichments of Metals, Including Methylmercury, in Sewage Spills in South Carolina, USA.

Exposure to microbial pathogens is the primary concern of sanitary sewer overflows; however, sewage spills may also be a significant source of toxic metals, including methylmercury (MeHg). Between November 2015 and January 2017, after Hurricane Joaquin, surface water samples were collected routinely from three creeks in Columbia, SC. Routine sampling coincided with six sewage spills.

Blood total mercury and methylmercury among pregnant mothers in Charleston, South Carolina, USA.

Background: Maternal blood total mercury (THg) is a biomarker for prenatal methylmercury (MeHg) exposure. Few studies have quantified both blood THg and MeHg during pregnancy, and few studies have reported longitudinal trends.

Objectives: We analyzed blood THg and MeHg in a cohort of pregnant mothers in Charleston, South Carolina (n = 83), and investigated whether blood THg or MeHg changed between early and late gestation.

Co-exposure to methylmercury and inorganic arsenic in baby rice cereals and rice-containing teething biscuits.

Background: Rice is an important dietary source for methylmercury (MeHg), a potent neurotoxin, and inorganic arsenic (As), a human carcinogen. Rice baby cereals are a dietary source of inorganic As; however, less is known concerning MeHg concentrations in rice baby cereals and rice teething biscuits.

Methods: MeHg concentrations were measured in 36 rice baby cereals, eight rice teething biscuits, and four baby cereals manufactured with oats/wheat (n = 48 total).

Stable Mercury Isotopes in Polished Rice (Oryza sativa L.) and Hair from Rice Consumers.

Mercury (Hg) isotopic signatures were characterized in polished rice samples from China, U.S., and Indonesia (n = 45).

Maternal methylmercury exposure through rice ingestion and offspring neurodevelopment: A prospective cohort study.

Background: Dietary methylmercury intake can occur not only through fish ingestion but also through rice ingestion; however, rice does not contain the same beneficial micronutrients as fish.

Objectives: In rural China, where rice is a staple food, associations between prenatal methylmercury exposure (assessed using maternal hair mercury) and impacts on offspring neurodevelopment were investigated.

Methods: A total of 398 mothers were recruited at parturition at which time a sample of scalp hair was collected.

Water management impacts rice methylmercury and the soil microbiome.

Rice farmers are pressured to grow rice using less water. The impacts of water-saving rice cultivation methods on rice methylmercury concentrations are uncertain. Rice (Oryza sativa L.

Low-level methylmercury exposure through rice ingestion in a cohort of pregnant mothers in rural China.

Background: Rice ingestion is an important dietary exposure pathway for methylmercury. There are few studies concerning prenatal methylmercury exposure through rice ingestion, yet the health risks are greatest to the developing fetus, and thus should be investigated.

Objectives: Our main objective was to quantify dietary methylmercury intake through rice and fish/shellfish ingestion among pregnant mothers living in southern China, where rice was a staple food and mercury contamination was considered minimal.

Spatiotemporal patterns of mercury accumulation in lake sediments of western North America.

For the Western North America Mercury Synthesis, we compiled mercury records from 165 dated sediment cores from 138 natural lakes across western North America. Lake sediments are accepted as faithful recorders of historical mercury accumulation rates, and regional and sub-regional temporal and spatial trends were analyzed with descriptive and inferential statistics. Mercury accumulation rates in sediments have increased, on average, four times (4×) from 1850 to 2000 and continue to increase by approximately 0.

The role of gut microbiota in fetal methylmercury exposure: Insights from a pilot study.

Purpose: The mechanisms by which gut microbiota contribute to methylmercury metabolism remain unclear. Among a cohort of pregnant mothers, the objectives of our pilot study were to determine (1) associations between gut microbiota and mercury concentrations in biomarkers (stool, hair and cord blood) and (2) the contributions of gut microbial mercury methylation/demethylation to stool methylmercury.

Methods: Pregnant women (36-39 weeks gestation, n=17) donated hair and stool specimens, and cord blood was collected for a subset (n=7).

The influence of obesity on blood mercury levels for U.S. non-pregnant adults and children: NHANES 2007-2010.

Background: In animal studies obesity is associated with higher blood and tissue mercury concentrations; however human studies are lacking. Although the mechanism underlying this association is uncertain, obesity may alter the metabolism and distribution of methylmercury.

Objectives: We determined whether obesity influenced blood mercury levels, the majority of which was methylmercury, for U.

Retrospective study of methylmercury and other metal(loid)s in Madagascar unpolished rice (Oryza sativa L.).

The rice ingestion rate in Madagascar is among the highest globally; however studies concerning metal(loid) concentrations in Madagascar rice are lacking. For Madagascar unpolished rice (n = 51 landraces), levels of toxic elements (e.g.

Rice methylmercury exposure and mitigation: a comprehensive review.

Rice cultivation practices from field preparation to post-harvest transform rice paddies into hot spots for microbial mercury methylation, converting less-toxic inorganic mercury to more-toxic methylmercury, which is likely translocated to rice grain. This review includes 51 studies reporting rice total mercury and/or methylmercury concentrations, based on rice (Orzya sativa) cultivated or purchased in 15 countries. Not surprisingly, both rice total mercury and methylmercury levels were significantly higher in polluted sites compared to non-polluted sites (Wilcoxon rank sum, p<0.

Prenatal methylmercury exposure through maternal rice ingestion: insights from a feasibility pilot in Guizhou Province, China.

Maternal hair and blood were investigated as biomarkers for prenatal methylmercury (MeHg) exposure among seventeen mothers recruited at parturition in Wanshan, Guizhou Province, China, where rice ingestion was the primary MeHg exposure pathway and atmospheric mercury (Hg) levels were elevated. For all three trimesters (n = 51), hair total Hg (THg) and MeHg concentrations ranged from 0.27 to 4.