Assessment of 12 Essential and Toxic Elements in Whole Blood of Pregnant and Non-pregnant Women Living in Wuhan of China

Predictors of urinary heavy metal concentrations among pregnant women in Jinan, China

BACKGROUND

Toxic heavy metal exposure and insufficiency or excess of essential heavy metals may have negative effects on pregnant women's health and fetal growth. To date, the predictors of pregnant women's heavy metal exposure levels remain unclear and vary with different regions. The study intended to explore potential predictors of exposure to heavy metals individually and high co-exposure to heavy metal mixtures.

METHODS

We recruited 298 pregnant women in first trimester from prenatal clinics in Jinan, Shandong Province, China, and collected spot urine samples and questionnaire data on their demographic characteristics, lifestyle habits, consumption of food and dietary supplement, and residential environment. All urine samples were analyzed for seven heavy metals: cobalt (Co), molybdenum (Mo), strontium (Sr), arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg).

RESULTS

Factors associated with single heavy metal concentration were as follows: a) urinary As, Sr and Cd increased with women's age respectively; b) pregnant women with higher monthly household income per capita had lower Sr and Mo levels; c) pregnant women with intermittent folic acid supplementation and those not taking tap water as domestic drinking water had lower Sr concentrations; d) Cd was positively linked with consumption frequency of rice; e) Hg was adversely related to consumption frequency of egg and the women who took purified water as domestic drinking water had lower Hg exposure. In addition, pregnant women's age was positively associated with odds of high co-exposure to Co, As, Sr, Mo, Cd and Pb; while those with an educational level of college had lower odds of high exposure to such a metal mixture compared with those whose educational levels were lower than high school.

CONCLUSION

Predictors of single urinary heavy metal concentration included pregnant women's age (As, Sr and Cd), monthly household income per capita (Sr and Mo), folic acid supplementation (Sr), rice consumption frequency (Cd), egg consumption frequency (Hg) and the type of domestic drinking water (Sr and Hg). Pregnant women with older age, lower educational level tended to have high co-exposure to Co, As, Sr, Mo, Cd and Pb.

Environmental exposure and child health in China

Chinese children are exposed to broad environmental risks ranging from well-known hazards, such as pesticides and heavy metals, to emerging threats including many new man-made chemicals. Although anecdotal evidence suggests that the exposure levels in Chinese children are substantially higher than those of children in developed countries, a systematic assessment is lacking. Further, while these exposures have been linked to a variety of childhood diseases, such as respiratory, endocrine, neurological, behavioral, and malignant disorders, the magnitude of the associations is often unclear. This review provides a current epidemiologic overview of commonly reported environmental contaminants and their potential impact on children's health in China. We found that despite a large volume of studies on various topics, there is a need for more high-quality research and better-coordinated regional and national data collection. Moreover, prevention of such diseases will depend not only on training of environmental health professionals and enhanced research programs, but also on public education, legislation, and networking.

Role of mineral nutrients other than iron in pregnancy: under recognized opportunities to improve maternal/fetal outcomes: a literature review

BACKGROUND

Anemia during pregnancy is an important global health concern, affecting 40% of women worldwide, and iron deficiency shares a significant proportion of the burden. From conception to birth, pregnancy is a period when women undergo metabolic and physiological changes. The nutritional needs are higher during pregnancy; thus, adequate nutrition is essential to maintain fetal growth and development. However, adverse effects due to deficiency in nutrition during pregnancy can result in maternal, fetal and neonatal complications. Despite the multifactorial etiology of anemia, iron deficiency is assumed as the primary cause of anemia during pregnancy and hence, mitigation strategy pivots around it for anemia management. Therefore, excluding other contributors, a single-micronutrient approach with iron supplements remains a myopic approach and this can exacerbate iron deficiency anemia. Micronutrient deficiencies are of particular concern as they may pose a silent threat to the survival and well-being of reproductive-age women and their infants.

AIM

Micronutrients, especially trace minerals, play a myriad of roles in pregnancy, and the lack of each one causes adverse complications to both the mother and the fetus. In this review paper, we attempt to piece together available information regarding the adverse effects of abnormal trace mineral levels along with iron deficiency on the mother and the fetus.

METHOD

A non-systematic literature search in PubMed, Google Scholar, and the Cochrane databases, for publications on minerals and vitamins during pregnancy and the possible influence of supplements on pregnancy outcomes.

CONCLUSION

Micronutrient deficiency exacerbates the pregnancy-induced anemia and other adverse birth outcomes. Micronutrient supplementation during pregnancy can combat anemia as well as reduce a number of adverse pregnancy outcomes in a comprehensive manner.

Variations in Blood Copper and Possible Mechanisms During Pregnancy

Copper (Cu), an essential trace element, is crucial for both the mother and fetus. Currently, an increasing number of studies have focused on blood copper levels during pregnancy. Studies have found that blood copper levels in pregnant women are higher than those in reproductive-age women, but the trend, mainly in the 2nd and 3rd trimester, is still controversial. Most studies showed that blood copper levels gradually increased during pregnancy, while some studies found that blood copper levels remained stable or even decreased in the 3rd trimester. The possible mechanisms of variations in blood copper during pregnancy include the influence of estrogen (hepatic uptake and excretion, ceruloplasmin synthesis, maternal-fetal transport, etc.), the interaction of other trace elements (Fe, Zn, etc.) and other factors. Among them, maternal-fetal copper transport caused by elevated estrogen may be the main reason for the inconsistencies observed in the 2nd and 3rd trimester during pregnancy. However, there are some mechanisms require further investigation. In the future, the trend and mechanisms of blood copper during pregnancy should be explored more deeply to help doctors better monitor copper status and detect copper abnormalities in time.

Assessment of 13 essential and toxic trace elements in tumor and peritumoral brain tissues from human glioblastoma

Trace elements within the brain are important for proper neurological function, but their imbalance has been rarely investigated in glioblastoma. This study enrolled a total of 14 patients with glioblastoma, and the tumor and peritumoral brain tissues were collected while undergoing surgery. The concentrations of Mg, Ca, Cr, Mn, Fe, Co, Cu, Zn, Se, As, Cd, Tl and Pb were determined using a well-evaluated ICP-MS method. The Cu- and Cd-binding proteomes were further analyzed using the anatomic transcriptional atlas from Ivy GAP. Histological evaluation was based on rubeanic acid staining and immunohistochemistry, respectively. The 13 trace element concentrations were obtained, and the highest were Ca, Mn, Fe, Zn and Cu, ranging from a few to dozens of ug/g. Correlation analysis suggested the existence of two intra-correlated clusters: essential metals (Cu-Ca-Zn-Mg) and heavy metals (Pb-As-Cd-Tl-Co-Cr-Mn). Compared to the tumor samples, significantly higher levels of Cu and Cd were observed in the peritumoral region. Further analysis of the Cu- and Cd-binding proteins from the anatomic view suggested that DBH and NOS1 were obviously increased in the leading edge than the central tumor region. Consistent with the above findings, histological evaluation of Cu and DBH further confirmed more copper and DBH expressions in the peritumoral area compared to the tumor core. Trace elements differ in tumor and peritumoral brain zone in glioblastoma, which may associate with tumor angiogenesis.

Associations of plasma manganese with adverse pregnancy outcomes: Nested case-control studies in a Chinese birth cohort

Both insufficient and excessive manganese exposure are associated with adverse pregnancy outcomes. However, no systematic research has established a standardized reference range for manganese levels with the consideration of the associated health risks during pregnancy. To verify the associations of prenatal manganese exposure with adverse outcomes and to identify a proper reference range for manganese based on health risks, we designed three nested case-control studies on three adverse outcomes including hypertensive disorders of pregnancy (HDP), preterm birth (PTB), and low birth weight (LBW) to investigate the associations with manganese levels. Plasma manganese concentrations in early pregnancy were measured. Conditional logistic regression analyses were used to estimate the associations of manganese levels with adverse outcomes. Restricted cubic spline (RCS) models were used to characterize the dose-response relationship of manganese and each outcome. Nonlinear associations were observed for manganese and adverse outcomes. Compared with women in the middle tertile of plasma manganese, we found that those in the highest tertile had a significantly higher risk of HDP (OR = 1.72, 95% CI: 1.02 to 2.89), that women in the lowest tertile had almost a tripled risk of delivering LBW infants (OR = 2.93, 95% CI: 1.67 to 5.17), and that women both in the lowest and the highest tertiles had significantly higher risks of PTB [OR = 1.83 (95% CI: 1.14 to 2.95); OR = 1.70 (95% CI: 1.05 to 2.76)]. U-shaped associations were found between plasma manganese and risk of PTB and infant LBW. Based on the results of RCS models, we identified a proper plasma manganese range of 1.72-3.18 μg/L, with relatively lower risks of adverse pregnancy outcomes. In conclusion, our study found U-shaped associations between manganese exposure and adverse pregnancy outcomes, and provided an optimal range of manganese concentration for pregnant women, based on health risk considerations.

Early-life manganese exposure during multiple developmental periods and adolescent verbal learning and memory

BACKGROUND

Manganese (Mn) is both an essential and toxic metal, and associations with neurodevelopment depend on exposure timing. Prospective data examining early life Mn with adolescent cognition are sparse.

METHODS

We enrolled 140 Italian adolescents (10-14 years old) from the Public Health Impact of Metals Exposure study. Mn in deciduous teeth was measured using laser ablation-mass spectrometry to represent prenatal, postnatal and early childhood exposure. The California Verbal Learning Test for Children (CVLT-C) was administered to assess adolescent verbal learning and memory. Multivariable regression models estimated changes in CVLT-C scores and the odds of making an error per doubling in dentine Mn in each exposure period. Multiple informant models tested for differences in associations across exposure periods.

RESULTS

A doubling in prenatal dentine Mn levels was associated with lower odds of making an intrusion error (OR = 0.23 [95% CI: 0.09, 0.61]). This beneficial association was not observed in other exposure periods. A doubling in childhood Mn was beneficially associated with short delay free recall: (ß = 0.47 [95% CI: -0.02, 0.97]), which was stronger in males (ß = 0.94 [95% CI: 0.05, 1.82]). Associations were null in the postnatal period.

CONCLUSION

Exposure timing is critical for understanding Mn-associated changes in cognitive function.

Trimester-specific effects of maternal exposure to single and mixed metals on cord serum inflammatory cytokines levels: A prospective birth cohort study

BACKGROUND

Cord blood inflammatory cytokines are vital in early-life programming. An increasing number of studies concern the effect of maternal exposure to different metal elements during pregnancy on inflammatory cytokines, but limited studies have explored the association between maternal exposure to mixed metals and cord blood inflammatory cytokine levels.

METHODS

We measured serum concentrations of vanadium (V), copper (Cu), arsenic (As), cadmium (Cd), and barium (Ba) in the first, second, and third trimesters and eight cord serum inflammatory cytokines (IFN-γ, IL-1β, IL-6, IL-8, IL-10, IL-12p70, IL-17A, and TNF-α) in 1436 mother-child dyads from the Ma'anshan Birth Cohort. Generalized linear models and Bayesian kernel machine regression (BKMR) were performed to assess the association of single and mixed metal exposure during each trimester with cord serum inflammatory cytokine levels, respectively.

RESULTS

Regarding metal exposure in the first trimester, V was positively associated with TNF-α (β = 0.33, 95 % CI: 0.13, 0.53); Cu was positively associated with IL-8 (β = 0.23, 95 % CI: 0.07, 0.39); Ba was positively associated with IFN-γ and IL-6; As was negatively associated with IFN-γ and IL-17A; and Cd was negatively associated with IFN-γ, IL-1β, IL-12p70, IL-17A, and TNF-α. BKMR revealed that exposure to metal mixtures in the first trimester was positively associated with IL-8 and TNF-α but negatively associated with IL-17A. Moreover, V contributed the most to these associations. Interaction effects were observed between Cd and As and between Cd and Cu with IL-8, and between Cd and V with IL-17A. Among males, As decreased inflammatory cytokines; among females, Cu increased inflammatory cytokine levels, whereas Cd decreased inflammatory cytokine concentrations.

CONCLUSIONS

Maternal exposure to metal mixtures in the first trimester interfered with cord serum inflammatory cytokine levels. The associations of maternal exposure to As, Cu and Cd with inflammatory cytokines showed sex differences. Further studies are warranted to support the findings and explore the mechanism of the susceptibility window and sex-specific disparity.

Maternal blood concentrations of toxic metal(loid)s and trace elements from preconception to pregnancy and transplacental passage to fetuses

Intrauterine exposure to heavy metals may adversely affect the developing fetus and health later in life, while certain trace elements may be protective. There is limited data on their dynamic fluctuation in circulating concentration of women from preconception to pregnancy and the degree of transplacental passage to fetus. Such information is critically needed for an optimal design of research studies and intervention strategies. In the present study, we profiled the longitudinal patterns and trajectories of metal(loid)s and trace elements from preconception to late pregnancy and in newborns. We measured whole blood metal(loid)s in women at preconception, 16, 24 and 32 weeks of gestation and in cord blood in 100 mother-newborn pairs. Our data showed that the mean concentrations of mercury (Hg), lead (Pb), rubidium (Rb), manganese (Mn), and iron (Fe) were lower during early-, mid-, and late-pregnancy than at preconception. Copper (Cu), and calcium (Ca) concentrations increased after pregnancy (Cu 798 versus 1353, 1488, and 1464 μg/L). Concentrations at preconception were correlated with those during pregnancy for all examined metal(loid)s. Maternal Hg, Pb, and Se concentrations at late-pregnancy were correlated with those in newborn cord blood in various degrees (correlation coefficients: Hg 0.66, Pb 0.29, Se 0.39). The estimated placental transfer ratio for toxic metal(loid)s ranging from 1.68 (Hg) to 0.18 (Cd). Two trajectory groups were identified for Hg, Pb, Cd, Se concentrations. Hg concentrations may be correlated with maternal education levels. The study is the first to present longitudinal circulating concentration trajectories of toxic metal(loid)s and trace elements from preconception to pregnancy stages. A high degree of transplacental passage was observed in toxic metals Pb and Hg which may pose hazards to the developing fetus.

The Long-Term Effect of Maternal Iron Levels in the Second Trimester on Mild Thinness among Preschoolers: The Modifying Effect of Small for Gestational Age

The supplementation of multiple micronutrients throughout pregnancy can reduce the risk of adverse birth outcomes and various diseases in children. However, the long-term effect of maternal multiple micronutrient levels in the second trimester on the overall development of preschoolers remains unknown. Therefore, 1017 singleton mother-infant pairs and 6-year-old preschoolers were recruited based on the China-Wuxi Birth Cohort Study. Meanwhile, information on the demographic characteristics of pregnant women and preschoolers, maternal copper, calcium, iron, magnesium, and zinc levels in whole blood during the second trimester, and neonatal outcomes, were collected. We aimed to investigate the long-term impact of maternal copper, calcium, iron, magnesium, and zinc levels in the second trimester on mild thinness among 6-year-old preschoolers, and the modifying effect of small for gestational age (SGA), within the Chinese population. Multiple logistic regression models revealed that high-level maternal iron in the second trimester reduced the risk of mild thinness [adjusted OR: 0.46 (95% CI: 0.26, 0.80)] among 6-year-old preschoolers. However, no significant association was found for the remaining four maternal essential metal elements. Additionally, the restricted cubic spline function showed that the risk of mild thinness decreased when maternal iron concentration exceeded 7.47 mmol/L in whole blood during the second trimester. Furthermore, subgroup analysis indicated that the long-term protective effect of high-level maternal iron on mild thinness was only observed in SGA infants. Summarily, high-level maternal iron in the second trimester distinctly lowers the risk of mild thinness among 6-year-old preschoolers, especially in preschoolers with birth outcomes of SGA. Our findings offer evidence for the implementation of iron supplementation in the second trimester as a preventive measure against mild thinness in children.

Association between whole blood essential trace elements and cognitive function in older adults

BACKGROUND

Essential trace elements (ETEs) are essential nutrients for keeping the nervous system functioning. Associations between ETEs and cognitive function are still inconclusive and limited.

OBJECTIVES

We aimed to investigate the individual and joint associations between ETEs and cognitive function among older adults.

METHODS

A population (N = 2181) at an average age≥ 65 from Yiwu cohort in China was available for this study. Whole blood chromium (Cr), selenium (Se), manganese (Mn), and copper (Cu) concentrations were measured by inductively coupled plasma mass spectrometry (ICP-MS). Cognitive function was assessed using the Mini-Mental State Examination (MMSE), consisting of five specific cognitive domains: orientation, registry, attention and calculation, recall, and language and praxis. Linear regression, restricted cubic spline (RCS) analysis, and Bayesian kernel machine regression (BKMR) were used to analyze the individual and joint associations between ETEs and cognitive function.

RESULTS

The association between Cr and MMSE score presented an inverted-U shape (Q3 versus Q1: β = 0.774, 95 % CI: 0.297, 1.250; Q4 versus Q1: β = 0.481, 95 % CI: 0.006, 0.956); and Cr was especially associated with the registry, recall, and language and praxis. Per IQR (36.32 μg/L) increase of Se was positively associated with the MMSE score (β = 0.497, 95 % CI: 0.277, 0.717) and all five cognitive domains. The BKMR showed that the dose-response association between Se and cognitive function increased initially and then decreased with increasing Se concentration when fixed the other ETEs in median. ETEs mixture was positively associated with cognitive function, and Se (posterior inclusion probabilities, PIPs = 0.915) was the most important contributor within the ETEs mixture.

CONCLUSIONS

The nonlinear association between Cr and cognitive function suggested further exploration of an appropriate concentration range for ETEs. A positive association between mixed ETEs and cognitive function is a reminder that their joint association should be considered. Further prospective studies or intervention studies are warranted to validate our findings in the future.

Association of Maternal Plasma Manganese with the Risk of Spontaneous Preterm Birth: A Nested Case–Control Study Based on the Beijing Birth Cohort Study (BBCS) in China

We performed this study to clarify the dynamic changes in maternal manganese (Mn) concentration during pregnancy and its association with spontaneous preterm birth (SPB). A nested case–control study was conducted based on the Beijing Birth Cohort Study (BBCS) from 2018 to 2020. Singleton pregnancy women aged 18–44 (n = 488) were involved in the study, including 244 cases of SPB and 244 controls. All of the participants provided blood samples twice (in their first and third trimesters). Inductively coupled plasma mass spectrometry (ICP-MS) was used for the laboratory analysis, and unconditional logistic regression was used for the statistical analysis. We found that the maternal Mn levels were significantly higher in the third trimester than those in the first trimester (median: 1.23 vs. 0.81 ng/mL). The SPB risk was increased to 1.65 (95% CI: 1.04–2.62, p = 0.035) in the highest Mn level (third tertile) in the third trimester, especially in normal-weight women (OR: 2.07, 95% CI: 1.18–3.61, p = 0.011) or non-premature rupture of membrane (PROM) women (OR: 3.93, 95% CI: 2.00–7.74, p < 0.001). Moreover, a dose-dependent relationship exists between the SPB risk and maternal Mn concentration in non-PROM women (P trend < 0.001). In conclusion, dynamic monitoring of maternal Mn level during pregnancy would be helpful for SPB prevention, especially in normal-weight and non-PROM women.

Association between prenatal metals exposure and blood pressure in 5-6 years children: A birth cohort study

BACKGROUND

The trajectory of blood pressure (BP) from childhood to early middle age suggested that individuals with elevated BP in early childhood were more likely to be affected by cardiovascular disease in adulthood. Exposure to metals may affect BP in children, and pregnancy is a sensitive time for metal exposure. This study assessed the relationship between different stages of prenatal exposure to metals or metal mixtures and BP in children aged 5-6 years.

METHODS

The study included 2535, 2680, 2534 mother-child pairs in three trimesters, from the Ma'anshan birth cohort study (MABC). We collected maternal blood samples during pregnancy and measured the serum levels of four metals (arsenic, selenium, cadmium, and mercury). BP was measured in children aged 5-6 years. A linear regression model and Bayesian kernel machine regression (BKMR) were used to explore associations between prenatal exposure to metals at different stages and multiple metal exposure with BP in children aged 5-6 years.

RESULTS

Associations were observed between the arsenic in the third trimester and children's diastolic blood pressure (DBP) (β = 0.88, 95% CI: 0.44, 1.33), systolic blood pressure (SBP) (β = 0.72, 95% CI: 0.19, 1.24) and mean arterial pressure (MAP) (β = 0.83, 95% CI: 0.42, 1.23), as well as between the mercury and children's DBP (β = 0.65, 95% CI: 0.13, 1.16) and MAP (β = 0.60, 95% CI: 0.14, 1.07). The BKMR analysis showed that multiple metals had a significant positive joint effect on children's DBP, SBP and MAP. A potential interaction between arsenic and mercury was observed (β = -0.85, 95% CI: -1.62, -0.08).

CONCLUSIONS

Exposure to arsenic and mercury during pregnancy was associated with altered BP in children. The third trimester may represent an important window of opportunity to reduce the effects of metal exposure on children's blood pressure and long-term health.

An Insight into the Impact of Serum Tellurium, Thallium, Osmium and Antimony on the Antioxidant/Redox Status of PCOS Patients: A Comprehensive Study

Humans exploit heavy metals for various industrial and economic reasons. Although some heavy metals are essential for normal physiology, others such as Tellurium (Te), Thallium (TI), antimony (Sb), and Osmium (Os) are highly toxic and can lead to Polycystic Ovarian Syndrome (PCOS), a common female factor of infertility. The current study was undertaken to determine levels of the heavy metals TI, Te, Sb and Os in serum of PCOS females (n = 50) compared to healthy non-PCOS controls (n = 56), and to relate such levels with Total Antioxidant Capacity (TAC), activity of key antioxidant enzymes, oxidative stress marker levels and redox status. PCOS serum samples demonstrated significantly higher levels of TI, Te, Sb and Os and diminished TAC compared to control (p < 0.001). Furthermore, there was significant inhibition of SOD, CAT and several glutathione-related enzyme activities in sera of PCOS patients with concurrent elevations in superoxide anions, hydrogen and lipid peroxides, and protein carbonyls, along with disrupted glutathione homeostasis compared to those of controls (p < 0.001 for all parameters). Additionally, a significant negative correlation was found between the elevated levels of heavy metals and TAC, indicative of the role of metal-induced oxidative stress as a prominent phenomenon associated with the pathophysiology of the underlying PCOS. Data obtained in the study suggest toxic metals as risk factors causing PCOS, and thus protective measures should be considered to minimize exposure to prevent such reproductive anomalies.

Associations Between Mild Cognitive Impairment and Whole Blood Zinc and Selenium in the Elderly Cohort

Some studies have shown that an imbalance in trace element homeostasis can lead to cognitive dysfunction, but data are lacking. The purpose of this study was to investigate the association between whole blood zinc (Zn), selenium (Se), copper-zinc ratio (Cu/Zn), copper-selenium ratio (Cu/Se), and zinc-selenium ratio (Zn/Se) and mild cognitive impairment (MCI) in elderly Chinese individuals. The study was based on the Elderly Health and Controlled Environmental Factors Cohort in Lu'an, Anhui Province, China, from June to September 2016. The cognitive function of the elderly was determined by the Mini-Mental State Examination (MMSE) and activities of daily living (ADL) scales. The concentrations of Zn, Cu, and Se in the whole blood were measured by inductively coupled plasma-mass spectrometry (ICP-MS). Binary logistic regression was used to analyze the associations between trace elements and MCI. A total of 1006 participants with an average age of 71.70 years old were included in this study. Compared with healthy people, MCI patients had higher whole blood Zn levels and lower Se levels, and Cu/Zn, Cu/Se, and Zn/Se were also significantly different. Binary logistic regression analysis showed that Zn, Cu/Se, and Zn/Se exposure in the third tertile was associated with an increased risk of MCI, while Se exposure in the third tertile was associated with a reduced risk of MCI. After adjustment for sex, age, marital status, BMI, and living status, whole blood Zn, Se, Cu/Zn, Cu/Se, and Zn/Se were significantly associated with MCI risk, especially in elderly women.

Association of whole blood metals/metalloids with severity in sepsis patients: A prospective, single-center, pilot study

BACKGROUND

Trace metals/metalloids were important for the biological functions of both the eukaryotic host and the microorganism. Their concentrations and variations may associate with the critical illness in sepsis, which still needs to be investigated.

METHODS

We performed a prospective cohort study on the patients with sepsis admitted to Tongji hospital (Wuhan, China) from Jul 01 to Dec 31, 2021. Sepsis was diagnosed in accordance with the third international consensus definitions for sepsis and septic shock (Sepsis-3). The concentrations of metals/metalloids including magnesium (Mg), calcium (Ca), chromium (Cr), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), mercury (Hg), thallium (Tl) and lead (Pb) in whole blood were analyzed by ICP-MS based methods.

RESULTS

Compared to the healthy controls, patients with sepsis showed higher levels of Ca, Cr and Cu, and lower levels of Mg, Mn, Fe, Zn, As, Hg and Pb. Further analysis between the critical illness and noncritical illness, revealed the Mn, Fe were significantly lower in the critically-ill sepsis. The longitudinal profile of the two metals show the differences appeared to exist almost throughout the clinical course. By performing the binary regression logistic analysis, we determined the Fe, Mn as independently risk factors for critical illness in sepsis, with effect sizes (β) of 17.14 (95%CI: 1.79-163.81) and 10.83 (1.96-59.83), respectively, which collectively discriminated 83.3% of all cases between critical-illness and non-critically illness.

CONCLUSIONS

The variations of whole blood metals/metalloids were associated with the critically-ill sepsis.

The associations of serum metals concentrations with the intermediate and pregnancy outcomes in women undergoing in vitro fertilization (IVF)

BACKGROUND

Toxic and essential trace elements are reported to have impact on female fertility. However, studies on the potential synergistic or antagonistic effects of metal mixtures on IVF outcomes remain limited.

OBJECTIVE

To evaluate whether serum concentrations of metals, individually and as mixtures, are associated with pregnancy outcomes in women undergoing IVF.

METHODS

In a prospective birth cohort study about IVF from the First Affiliated Hospital of Anhui Medical University (n = 1184), we measured the concentrations of serum metals by ICP-MS according to a previously established method. Oocyte/embryo development indicators and follow-up results were also collected. The individual and joint effects of metals were estimated using logistic regressions and Bayesian kernel machine regressions (BKMR).

RESULTS

At embryonic stage, we found negative associations between the serum lead (Pb) (β = -0.14, 95%CI: -0.32, -0.04) and cadmium (Cd) (β = -0.24, 95%CI: -0.39, -0.09) concentrations and the high-quality embryos rate; and positive associations between the serum cobalt (Co) (β = 0.18, 95%CI: 0.05, 0.31) and selenium (Se) (β = 0.17, 95%CI: 0.06, 0.41) concentrations and the MII rate. Regarding to the pregnancy outcomes, the serum Pb was negatively related with successful implantation (OR=0.85, 95%CI: 0.77, 0.94) and clinical pregnancy (OR=0.95, 95%CI: 0.91, 0.99); and positively associated with spontaneous abortion (OR=1.39, 95% CI: 1.02, 1.91). The BKMR analysis showed linear or parabolic associations between the metal mixtures and pregnancy outcomes, with Pb showing the highest posterior inclusion probabilities.

CONCLUSIONS

The toxic (Pb, Cd) and essential (Co, Se) metals could be incorporated as simultaneous predictors of IVF outcomes including potential antagonistic effects, in which Pb exhibits major contributions.

Influence of Dietary Compounds on Arsenic Metabolism and Toxicity. Part II-Human Studies

Exposure to various forms of arsenic (As), the source of which may be environmental as well as occupational exposure, is associated with many adverse health effects. Therefore, methods to reduce the adverse effects of As on the human body are being sought. Research in this area focuses, among other topics, on the dietary compounds that are involved in the metabolism of this element. Therefore, the aim of this review was to analyze the influence of methionine, betaine, choline, folic acid, vitamin B2, B6, B12 and zinc on the efficiency of inorganic As (iAs) metabolism and the reduction in the severity of the whole spectrum of disorders related to As exposure. In this review, which included 62 original papers (human studies) we present the current knowledge in the area. In human studies, these compounds (methionine, choline, folic acid, vitamin B2, B6, B12 and zinc) may increase iAs metabolism and reduce toxicity, whereas their deficiency may impair iAs metabolism and increase As toxicity. Taking into account the results of studies conducted in populations exposed to As, it is reasonable to carry out prophylactic activities. In particular nutritional education seems to be important and should be focused on informing people that an adequate intake of those dietary compounds potentially has a modulating effect on iAs metabolism, thus, reducing its adverse effects on the body.

Study on Reference Range of Zinc, Copper and Copper/Zinc Ratio in Childbearing Women of China

Background: Copper and zinc are both essential elements in humans, that play various biological roles in body functions. Population-based reference values have not yet been established in China especially in childbearing women. The aim of this study is to establish a reference value of Zn, Cu and Cu/Zn ratios in childbearing women aged 18-44 from a representative population in China. Method: A total of 191 healthy childbearing women aged 18-44 years old were enrolled from the China Adult Chronic Disease and Nutrition Surveillance (2015) in this study with a series strict inclusion criteria. Basic biological indicators (weight, height, waist, blood pressure, high-density lipoprotein cholesterol, low-density lipoprotein, total cholesterol, triglyceride, fast glycose, HbA1c, blood pressure, uric acid) and elements levels in plasma and whole blood were collected. The 2.5th to 97.5th was used to represent the reference range of Cu, Zn and Cu/Zn ratio. Results: The reference range of Zn, Cu and Cu/Zn ratio in plasma were 70.46-177.53 µg/dL, 74.30-170.68 µg/dL and 0.54-1.68, respectively. The reference range of Zn, Cu and Cu/Zn ratios in whole blood were 402.49-738.05, 74.63-124.52 and 0.13-0.25 µg/dL, respectively. Conclusion: The reference range of Zn, Cu and Cu/Zn ratios in plasma and whole blood of healthy Chinese childbearing women could be used as an indicator to evaluate the status of element deficiency and overload.