Aluminum exposure and toxicity in neonates: a practical guide to halt aluminum overload in the prenatal and perinatal periods

Embryonic exposure to aluminum chloride blocks the onset of spermatogenesis through disturbing the dynamics of testicular tight junctions via upregulating Slc25a5 in offspring

Studies have revealed neurotoxicity, hepatotoxicity, and developmental and reproductive toxicity in mice exposed to aluminum. However, relatively few studies have been conducted to clarify the mechanism underlying the impact of embryonic exposure to aluminum on the development of the male reproductive system in offspring. Pregnant mice were administered aluminum chloride (AlCl3) by gavage from day 12.5 of gestation until birth. Our findings demonstrated that embryonic exposure to AlCl3 disrupted testicular development and spermatogenesis by impairing testicular architecture, reducing sperm count, and upregulating the expression of tight junction (TJ) protein between Sertoli cells (SCs). Further in vitro studies revealed that treatment with AlCl3 stabilized TJ proteins Occludin and ZO-1 expression by inhibiting ERK signaling pathway activation, thereby upregulating Slc25a5 expression which induced ATP production leading to disruption of cytoskeletal protein homeostasis. Therefore, the study provided a new mechanistic insight into how AlCl3 exposure interfered with testicular development and spermatogenesis while suggesting that Slc25a5 might be a target affected by AlCl3 influencing cell metabolism.

An Assessment of aluminum contamination in neonatal parenteral nutrition solutions based on measured versus labeled content

Aluminum can potentially cause toxicity in pediatrics and neonates receiving parenteral nutrition. Some PN solutions and ingredients in Saudi Arabia do not comply with US FDA regulations regarding aluminum exposure. This study aims to determine the aluminum concentration in samples of PN solutions and ingredients used to feed infants in Saudi Arabia. The aluminum in the samples was determined using inductively coupled plasma mass spectrometry. The concentration of metal contaminants in each sample was determined in triplicate. The aluminum content of 38 samples was investigated, 15 of which originated from components included in the prepared PN solutions. Among the 15 samples, the least measurable aluminum content was detected in potassium chloride solutions (0.81 mcg/L). In contrast, the greatest amount of aluminum was detected in potassium phosphate and calcium gluconate (141,64 mcg/L and 462.7 mcg/L), respectively. The results showed that the final PN solution (PNS) product contained more aluminum levels than the content ingredients; in addition, the study found a statistically significant relationship among 18 pediatric patients at KFMC who had intestinal failure and needed long-term parenteral nutrition. Specifically, their high aluminum levels, exceeding the normal range of 0.6 ng/ml, indicate that the current use of PN solutions will likely cause toxicity due to aluminum contamination in additives. Hence, reducing aluminum in PN solutions is imperative to ensure patient safety.

A review of the epidemiological and laboratory evidence of the role of aluminum exposure in pathogenesis of cardiovascular diseases

The objective of the present study was to review the epidemiological and laboratory evidence on the role of aluminum (Al) exposure in the pathogenesis of cardiovascular diseases. Epidemiological data demonstrated an increased incidence of cardiovascular diseases (CVD), including hypertension and atherosclerosis in occupationally exposed subjects and hemodialysis patients. In addition, Al body burden was found to be elevated in patients with coronary heart disease, hypertension, and dyslipidemia. Laboratory studies demonstrated that Al exposure induced significant ultrastructural damage in the heart, resulting in electrocardiogram alterations in association with cardiomyocyte necrosis and apoptosis, inflammation, oxidative stress, inflammation, and mitochondrial dysfunction. In agreement with the epidemiological findings, laboratory data demonstrated dyslipidemia upon Al exposure, resulting from impaired hepatic lipid catabolism, as well as promotion of low-density lipoprotein oxidation. Al was also shown to inhibit paraoxonase 1 activity and to induce endothelial dysfunction and adhesion molecule expression, further promoting atherogenesis. The role of Al in hypertension was shown to be mediated by up-regulation of NADPH-oxidase, inhibition of nitric oxide bioavailability, and stimulation of renin-angiotensin-aldosterone system. It has been also demonstrated that Al exposure targets cerebral vasculature, which may be considered a link between Al exposure and cerebrovascular diseases. Findings from other tissues lend support that ferroptosis, pyroptosis, endoplasmic reticulum stress, and modulation of gut microbiome and metabolome are involved in the development of CVD upon Al exposure. A better understanding of the role of the cardiovascular system as a target for Al toxicity will be useful for risk assessment and the development of treatment and prevention strategies.

Cadmium exposure exacerbates immunological abnormalities in a BTBR T+ Itpr3tf/J autistic mouse model by upregulating inflammatory mediators in CD45R-expressing cells

Autism spectrum disorder (ASD) is a neurodevelopmental illness characterized by behavior, learning, communication, and social interaction abnormalities in various situations. Individuals with impairments usually exhibit restricted and repetitive actions. The actual cause of ASD is yet unknown. It is believed, however, that a mix of genetic and environmental factors may play a role in its development. Certain metals have been linked to the development of neurological diseases, and the prevalence of ASD has shown a positive association with industrialization. Cadmium chloride (Cd) is a neurotoxic chemical linked to cognitive impairment, tremors, and neurodegenerative diseases. The BTBR T+ Itpr3tf/J (BTBR) inbred mice are generally used as a model for ASD and display a range of autistic phenotypes. We looked at how Cd exposure affected the signaling of inflammatory mediators in CD45R-expressing cells in the BTBR mouse model of ASD. In this study, we looked at how Cd affected the expression of numerous markers in the spleen, including IFN-γ, IL-6, NF-κB p65, GM-CSF, iNOS, MCP-1, and Notch1. Furthermore, we investigated the effect of Cd exposure on the expression levels of numerous mRNA molecules in brain tissue, including IFN-γ, IL-6, NF-κB p65, GM-CSF, iNOS, MCP-1, and Notch1. The RT-PCR technique was used for this analysis. Cd exposure increased the number of CD45R+IFN-γ+, CD45R+IL-6+, CD45R+NF-κB p65+, CD45R+GM-CSF+, CD45R+GM-CSF+, CD45R+iNOS+, and CD45R+Notch1+ cells in the spleen of BTBR mice. Cd treatment also enhanced mRNA expression in brain tissue for IFN-γ, IL-6, NF-κB, GM-CSF, iNOS, MCP-1, and Notch1. In general, Cd increases the signaling of inflammatory mediators in BTBR mice. This study is the first to show that Cd exposure causes immune function dysregulation in the BTBR ASD mouse model. As a result, our study supports the role of Cd exposure in the development of ASD.

Maternal and Newborn Blood Aluminum Levels and Neurodevelopment of Infants: Is there a Need for Concern?

Aluminum is a neurotoxic element that enters the human body due to its widespread usage in daily life. It has the potential to affect the neurological development of the fetus and infant adversely. This study aimed to evaluate the relationship between maternal and umbilical cord serum aluminum level and infant neurodevelopment. Over a period of March 2018 to September 2019, we conducted a prospective cohort study; 173 Mother-new-born pairs were enrolled. Aluminum levels were measured using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The correlation with Bayley Scales of Infant Development (BSID) -3rd edition score and maternal and cord serum aluminum were assessed via linear regression model. The mean concentration of maternal and cord serum aluminum was 2.58 ± 1.14 µg/dL and 1.44 ± 0.62 µg/dL, respectively. There was a significant correlation in aluminum level between maternal and umbilical cord serum (Pearson's r = 0.591, p < 0.000). There is no significant correlation between maternal and serum aluminum level, and BSID-3rd edition (cognitive, motor, language, and social-emotion) score at the average age of 6.5 months. In conclusion, maternal and cord serum aluminum levels were significantly correlated but did not correlate with infant neurodevelopment. Thus, low serum aluminum concentration and their association with child neurodevelopment deserve further investigation longitudinally in a large cohort.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s12291-021-01002-y.

Early pregnancy PM2.5 exposure and its inorganic constituents affect fetal growth by interrupting maternal thyroid function

Early pregnancy is crucial for fetal growth. Maternal thyroid hormone is critical for fetal growth and can be disturbed under exogenous exposure. However, it's uncertain whether exposure to PM_2.5 and inorganic constituents during early pregnancy can affect TH and fetal growth. We focused on the associations of early-pregnancy PM_2.5 and inorganic constituents with fetal growth and maternal THs. PM_2.5 concentration was estimated using a satellite-based spatiotemporal model. Fetal biparietal diameter (BPD), head circumference (HC), femur length (FL), and humerus length (HL) were measured by ultrasonography at median 15.6, 22.2, and 33.1 gestational weeks. Levels of 28 PM_2.5 constituents were measured in a sub-group of 329 pregnancies. Maternal serum free thyroxine (fT4), free triiodothyronine, and thyroid-stimulating hormone levels were measured at 14 weeks of gestation. Mixed-effect models and multiple linear regression were applied to evaluate the associations of PM_2.5 and its constituents with fetal growth measures. Mediation analysis was used to examine the mediating role of the THs. Results showed that each 10 μg/m³ increase in PM_2.5 was associated with 0.20 mm reductions in BPD (95%CI: 0.33, -0.01), 0.27 mm decreases in FL (95%CI: 0.40, -0.13), and 0.36 decreases in HL (95%CI: 0.49, -0.23). Per 10 μg/m³ increment in PM_2.5 was correlated with 5.82% decreases in the fT4 level (95% CI: 8.61%, -2.96%). FT4 accounted for 14.3% of PM_2.5 exposure-induced change in BPD at first follow-up. Al (β = -2.91, 95%CI: 5.17, -0.66), Si (β = -1.20, 95%CI: 2.22, -0.19), K (β = -3.09, 95%CI: 5.41, -0.77), Mn (β = -47.20, 95%CI: 83.68, -10.79) and Zn (β = -3.02, 95%CI: 5.55, -0.49) were associated with decreased fetal BPD, especially in first follow-up. Zn (β = -38.12%, 95% CI: 58.52%, -8.61%) was also associated with decreased fT4 levels. Overall, early pregnancy exposure to PM_2.5 and its constituents was associated with fetal growth restriction and decreased maternal fT4 levels might mediate the effect of PM_2.5.

Aluminum intake in the neonatal phase disrupts endochondral ossification in rodents

OBJECTIVE

This study evaluated the effects of aluminum (Al) intake on endochondral ossification during the neonatal phase.

METHOD

Twelve male newborn Gerbils (Meriones unguiculatus) were randomly divided into control (C) and aluminum (Al) groups (n = 6 animals/group). From the 1st to 15th day of life, gerbils received an AlCl₃ solution (10 mg/kg/day) via gavage. The control group received only the saline solution. On the 16th day, their tibias were processed for paraffin embedding and were submitted to histomorphometric, histochemical, and immunohistochemical analyses.

RESULTS

In the epiphyseal cartilage Al did not affect the proteoglycan content or cell proliferation; however, it increased matrix metalloprotease-2 (MMP-2) immunostaining and the hypertrophic layer thickness. In bone, Al decreased trabeculae number, trabecular width, cortical bone width, and proliferation. Furthermore, the relative frequency of bone matrix and fibrillar collagen decreased 3.9% and 16.2%, respectively. The number of osteoclasts and osteocalcin digital optical density (D.O.D) remained the same.

CONCLUSION

The results suggest that Al intake during the neonatal period impairs endochondral ossification by affecting epiphyseal cartilage and bone architecture.

Nanocurcumin, Promising Potential Protective Agent Against Histopathological Damage in the Cerebral Cortex of Mice Induced by Aluminum Chloride

&lt;b&gt;Background and Objective:&lt;/b&gt; Aluminum (Al) is widely used in many aspects of daily life, such as food packaging, cooking utensil components, food additives, cosmetics and water distillation. This study aimed to evaluate the protective role of nanocurcumin on the cerebral cortex of one and two-month-old mice exposed to 200 mg kg&lt;sup&gt;&lt;/sup&gt;&lt;sup&gt;1&lt;/sup&gt; b.wt., aluminium. &lt;b&gt;Materials and Methods:&lt;/b&gt; The Swiss Webster mice were used in this study. The control group only received sterile distilled water, the Al group was administered 200 mg kg&lt;sup&gt;&lt;/sup&gt;&lt;sup&gt;1&lt;/sup&gt; b.wt., of AlCl&lt;sub&gt;3&lt;/sub&gt; solution and the Al+Na Cur group was administered 200 mg kg&lt;sup&gt;&lt;/sup&gt;&lt;sup&gt;1&lt;/sup&gt; b.wt., AlCl&lt;sub&gt;3&lt;/sub&gt;+200 mg kg&lt;sup&gt;&lt;/sup&gt;&lt;sup&gt;1&lt;/sup&gt; nanocurcumin by intraperitoneal injection. The nanocurcumin was administered one hour after AlCl&lt;sub&gt;3 &lt;/sub&gt;exposure and then on days 0, 3, 6, 9, 12, 15, 18, 21, 24, 27 and 30. All the mice were anaesthetized and their brains were collected and fixed in a neutral formalin buffer solution for histological analysis. The paraffin method was used in this study. &lt;b&gt;Results:&lt;/b&gt; The death of granular neuron cells and karyolysis cells and the vacuolation of the pyramid cell layer of the cerebral cortex could be prevented by the intraperitoneal administration of nanocurcumin. The effect of nanocurcumin administration on the Al group at two months of age was more effective than on the Al group at one month of age. &lt;b&gt;Conclusion:&lt;/b&gt; Nanocurcumin can be a promising candidate protective agent against cerebral cortex changes after aluminium administration.

The Role of Magnesium in Pregnancy and in Fetal Programming of Adult Diseases

Magnesium is an essential trace metal and a necessary factor for multiple biochemical functions in humans. Its role in biology is fundamental in over 600 enzymatic reactions implicated in protein synthesis, mitochondrial functions, neuromuscular activity, bone formation, and immune system competence. Magnesium status is relevant in fetal development during gestation and in the newborn growth during the perinatal period. Moreover, magnesium is able to influence fetal programming and disease presentation in childhood or adulthood. The aim of this review is to focus on this metal homeostasis, analyzing its normal values, the causes of hypomagnesemia, the interaction with drugs and other conditions, and the diseases associated with magnesium value alteration during pregnancy, in order to study its role in fetal programming of adult diseases. The data here reported clearly indicated the existence of a connection between magnesium status and human pathology starting from intrauterine life and extending into childhood and adulthood.

Aluminum environmental pollution: the silent killer

The concern about aluminum (Al) toxicity has been proven in various cases. Some cases are associated with the fact that Al is a neurotoxic substance that has been found in high levels in the brain tissues of Alzheimer's disease (AD), epilepsy, and autism patients. Other cases are related to infants, especially premature infants and ones with renal failure, who are at the risk of developing the central nervous system (CNS) and bone toxicity. This risk is a result of infants' exposure to Al from milk formulas, intravenous-feeding solutions, and possibly from aluminum-containing vaccinations. Furthermore, most antiperspirants contain  aluminum compounds that raise human exposure to toxic Al. This review paper is intended to discuss in detail the above concerns associated with aluminum, and hence urges the need for more studies exploring the effects of overexposure to Al and recommending mitigation actions.

Aluminum Content of Human Milk and Antiperspirant Use

Background: Aluminum exposure may originate from numerous sources, including antiperspirants. Aluminum toxicity can cause a wide range of neurological impairments. Infants are exposed to aluminum through human milk (HM), formulas, total-parenteral-nutrition and vaccines. Due to potential risk of toxicity to both infants and women, it has been advised that lactating women decrease their use of aluminum-based products and antiperspirants. Our study aimed to determine whether the use of aluminum-based antiperspirants (ABA) affects aluminum levels in HM. Methods: This cross-sectional study included healthy mothers who exclusively breastfed infants (1 week to 5 months). Questionnaires were used to collect data on demographics, antiperspirant use and aluminum exposure. Mothers were instructed to express HM during the morning at first breastfeeding session. Aluminum levels were measured by atomic absorption spectrometry with a 5 ppb limit of detection. Results: Fifteen of the 58 (26%) recruited mothers used an aluminum-free antiperspirant (AFA) and 43 (74%) used an ABA. The range of aluminum concentration in HM was 0-100.8 μg/L (mean 11.4 ± 17.4 μg/L). The median aluminum level (Q1-Q3) was 6.5 μg/L (5.2-11.9) and 5.2 μg/L (3.46-9.4) in the AFA and ABA groups, respectively (p = 0.19). The aluminum levels were not affected by maternal age, education, diet, number of children, infant age, lactation stage or self-reported aluminum exposure. Conclusion: The data from this preliminary study demonstrate that the use of an ABA by lactating mothers does not increase their HM aluminum content. Additional studies with a larger cohort are warranted to confirm these findings.

Copper-Induced Epigenetic Changes Shape the Clinical Phenotype in Wilson's Disease

Wilson's disease is a congenital disorder of copper metabolism whose pathogenesis remains, at least in part, unknown. Subjects carrying the same genotype may show completely different phenotypes, differing for the age at illness onset or for the hepatic, neurologic or psychiatric clinical presentation. The inability to find a unequivocal correlation between the type of mutation in the ATPase copper transporting beta (ATP7B) gene and the phenotypic manifestation, has encouraged many authors to look for epigenetic factors interacting with the genetic changes. Here, the evidences regarding the ability of copper overload to change the global DNA methylation status are discussed.

Aluminum and magnesium status during pregnancy and placenta oxidative stress and inflammatory mRNA expression: China Ma'anshan birth cohort study

The aim of this study was to explore the impact of prenatal Al and Mg on placental oxidative stress and inflammatory mRNA expression. A total of 2519 pregnant women from the China Ma'anshan birth cohort participated in this study. Al and Mg levels were measured by inductively coupled plasma mass spectrometry (ICP-MS). Placental stress and inflammatory mRNA expression were assessed by RT-PCR. The median Al levels in the first and second trimesters of pregnancy and in cord blood were higher than the corresponding median Mg levels. Predictors of lower Al and Mg levels included Han ethnicity and high education according to a mixed linear model. Multiple linear regression analysis revealed that Al and Al/Mg levels had a positive association with inflammatory mRNA expression and placental oxidative stress in the second trimester of pregnancy. A negative association existed between Al and Al/Mg levels and inflammatory mRNA expression and placenta oxidative stress in the cord blood, with the exception of IL-1β expression. In conclusion, prenatal Al and Mg status was associated with placental oxidative stress and inflammatory mRNA expression. More preclinical studies are needed to confirm the relevant mechanism.

Neurotoxic effects of combined exposures to aluminum and mercury in early life (infancy)

Aluminum and mercury are environmentally ubiquitous. Individually they are both neurotoxic elements with shared neuro-pathogenic pathways: oxidative stress, altered neurotransmission, and disruption of the neuroendocrine and immune systems. In the infant, Al and Hg differ in type of exposure, absorption, distribution (brain access), and metabolism. In environmentally associated exposure (breast milk and infant formulas) their co-occurrences fluctuate randomly, but in Thimerosal-containing vaccines (TCVs) they occur combined in a proprietary ratio; in these cases, low-doses of Thimerosal-ethylmercury (EtHg) and adjuvant-Al present the most widespread binary mixture in less developed countries. Although experimental studies at low doses of the binary Hg and Al mixture are rare, when studied individually they have been shown to affect neurological outcomes negatively. In invitro systems, comparative neurotoxicity between Al and Hg varies in relation to the measured parameters but seems less for Al than for Hg. While neurotoxicity of environmental Hg (mainly fish methyl-Hg, MeHg) is associated with neurobehavioral outcomes in children, environmental Al is not associated, except in certain clinical conditions. Therefore, the issues of their neurotoxic effects (singly or combined) are discussed. In the infant (up to six months) the organic-Hg and Al body burdens from a full TCV schedule are estimated to reach levels higher than that originating from breastfeeding or from high aluminum soy-based formulas. Despite worldwide exposure to both Al and Hg (inorganic Hg, MeHg, and Thimerosal/EtHg), our knowledge on this combined exposure is insufficient to predict their combined neurotoxic effects (and with other co-occurring neurotoxicants).

Factors associated with low birthweight: a case-control study in a city of Minas Gerais

OBJECTIVE To analyze the many factors regarding socioeconomic and healthcare-related variables linked to maternal diseases and the possible impact of the environmental disaster of Mariana, given the prenatal exposure to different water sources for human consumption that were associated with low birthweight in full-term live births in the Municipal Hospital of Governador Valadares, Minas Gerais. METHODS Case-control study, carried out with live births at the Municipal Hospital of Governador Valadares, from May 2017 to July 2018. The case group consisted of full-term live births and low birthweight, and the control group consisted of full-term live births with adequate weight, matched by gender and date of birth. For each case, two controls were selected. Data collection was performed through interviews with the puerperal women, and complementary information was obtained by analyzing the prenatal card and medical records. For data analysis, logistic regression was performed. RESULTS The study included 65 live births from the case group and 130 from the control group. After the analysis was adjusted for other factors under study, we found that the higher risks of low birthweight are associated with the first childbirth (OR = 2.033; 95%CI = 1.047-3.948; p = 0.036), smoking during pregnancy (OR = 2.850; 95%CI = 1.013-8.021; p = 0.047) and consumption of water supplied by the municipalities affected by the tailings from the Fundão dam failure (RC = 2.444; 95%CI = 1.203-4.965; p = 0.013). CONCLUSIONS The variables "water consumed during pregnancy," "previous pregnancies" and "maternal smoking" were associated with low birthweight in the population studied. The importance of epidemiological studies that assess water quality and its adverse health effects is reinforced, as well as greater prenatal control of first-time pregnant women and greater support of policies against smoking, especially during pregnancy.

Occurrence, sources, and pathways of chemical contaminants in infant formulas

Infant formulas are manufactured products to meet specific nutritional requirements for infants. However, infant formulas can contain harmful substances, such as chemical contaminants and residues, normally due to possible contamination of the raw material or from the production chain. Some studies have demonstrated that veterinary drugs, pesticides, mycotoxins, heavy metals, packaging materials, within other chemicals are found in infant formulas from different sources of contamination. It is known that some of these substances can be hepatotoxic, carcinogenic, teratogenic, mutagenic, immunotoxic, contributing to antibiotic resistance, among other detrimental consequences for consumers' health. The purpose of this review is to assess the scientific evidence concerning the occurrence, sources, and pathways of contamination, as well as the detrimental impacts on infant health due to the possible presence of chemical contaminants and residues in infant formulas. Moreover, strategies to reduce the risk of contamination of infant formulas are presented to ensure the highest standards of quality of infant formulas. The entire infant formula manufacturing process should be monitored and controlled to minimize the risk of contamination during processing, storage, and distribution, besides ensuring the use of raw materials with as low as acceptable levels of harmful substances in order to assure that the final product shall comply with the maximum levels and maximum residue limits, when established, for residues and contaminants in the final product.

Neonatal exposure to aluminum chloride disrupts branching morphogenesis and hormonal signaling of the ventral male prostate and female prostate of gerbils

BACKGROUNG

Exposure to environmental pollutants in critical developmental windows may predispose the prostate to permanent changes in its homeostasis. Thus, it is essential to know the effects that environmental toxics, such as aluminum, can cause during the development of this gland. The aim of this study was to evaluate the effects of neonatal aluminum exposure on the ventral male prostate and the female prostate of 15 days old gerbils.

METHODS

Male and female gerbils were exposed orally to 10 mg/kg/day of aluminum chloride from the 1st to the 14th postnatal day life. At 15 days of life, gerbils were euthanized and their prostates were collected for biometric, morphological, morphometric, immunohistochemical and three-dimensional reconstruction analyzes.

RESULTS

Al exposure caused a reduction in body weight in males and a significant increase in serum testosterone levels in females. Prostate branching morphogenesis was intensified in males, who had greater length, number and area of prostatic epithelial buds. Additionally, Al altered the prostate hormonal regulation of males and females, causing up regulation of the androgen receptor and estrogen receptor alpha in the female prostate, and increased immunostaining of the androgen receptor in the ventral male prostate. These changes were associated with an increased rate of epithelial and stromal cell proliferation in both sexes.

CONCLUSION

Together, these results indicate that Al altered the neonatal development of the prostate and that this metal acted as an endocrine disruptor in this gland.

In Utero Exposure to Aluminium and Other Neurotoxic Elements in Urban Coastal South African Women at Delivery: An Emerging Concern

Aluminium (Al) is a non-essential neurotoxicant and there is limited information regarding exposure to Al in utero. This study sought to evaluate the in utero exposure to Al in urban South African women, its effects on birth outcomes and possible synergistic effects between Al, essential and neurotoxic elements such as lead (Pb), mercury (Hg) and arsenic (As), as well as a a potential sex-dependent response to these elements in neonates. This study has found elevated levels of Al in urban women at delivery. The Spearman’s rank correlation coefficients (p-value) of the association between maternal serum Al and birth outcomes (gestational age and parity), and between maternal serum Al and Cu, Zn and Se, were statistically significant. However, in the general and the stratified models, no association was found between any of the birth outcomes and maternal serum Al. The association between maternal serum Al and neurotoxic elements at delivery showed a significant positive correlation for Pb only (rho = 0.361; p < 0.001) which was found to be sex-dependent in neonates (males, rho = 0.285; p < 0.004 and females, rho = 0.444, p < 0.001). Our preliminary findings indicate that in utero exposure to Al is an emerging concern requiring further research and directives from public health authorities.

Acute exposure and chronic retention of aluminum in three vaccine schedules and effects of genetic and environmental variation

Like the mechanisms of action as adjuvants, the pharmacodynamics of injected forms of aluminum commonly used in vaccines are not well-characterized, particularly with respect to how differences in schedules impact accumulation and how factors such as genetics and environmental influences on detoxification influence clearance. Previous modeling efforts are based on very little empirical data, with the model by Priest based on whole-body clearance rates estimated from a study involving a single human subject. In this analysis, we explore the expected acute exposures and longer-term whole-body accumulation/clearance across three vaccination schedules: the current US Centers for Disease Control and Prevention (CDC) schedule, the current CDC schedule using low aluminum or no aluminum vaccines, and Dr. Paul Thomas' "Vaccine Friendly Plan" schedule. We then study the effects of an implicit assumption of the Priest model on whether clearance dynamics from successive doses are influenced by the current level of aluminum or modeled by the assumption that a new dose has its own whole-body dynamics "reset" on the day of injection. We model two additional factors: variation (deficiency) in aluminum detoxification, and a factor added to the Priest equation to model the potential impact of aluminum itself on cellular and whole-body detoxification. These explorations are compared to a previously estimated pediatric dose limit (PDL) of whole-body aluminum exposure and provide a new statistic: %alumTox, the (expected) percentage of days (or weeks) an infant is in aluminum toxicity, reflecting chronic toxicity. We show that among three schedules, the CDC schedule results in the highest %alumTox regardless of model assumptions, and the Vaccine Friendly Plan schedule, which avoids >1 ACV per office visit results in the lowest (expected) %alumTox. These results are conservative, as the MSL is derived from data used by FDA to estimate safety of aluminum in adult humans. These results demonstrate high potential utility of modeling variation in patient responses to aluminum. More empirical data from individuals who are suspected of being intolerant of aluminum from vaccines, evidenced by high aluminum retention, neurodevelopmental disorders and/or a myriad of chronic illnesses would help answer questions on whether the model predictions can be used to estimate parameter values tied to genetic factors including genomic sequence variation and family history of chronic illnesses tied to aluminum exposure.

Prescription Infant Formulas Are Contaminated with Aluminium

Historical and recent data demonstrate that off-the-shelf infant formulas are heavily contaminated with aluminium. The origin of this contamination remains to be elucidated though may be imported via ingredients, packaging and processing. Specialised infant formulas exist to address health issues, such as low birth weight, allergy or intolerance and medical conditions, such as renal insufficiency. The aluminium content of these prescription infant formulas is measured here for the first time. We obtained 24 prescription infant formulas through a paediatric clinic and measured their total aluminium content by transversely heated graphite furnace atomic absorption spectrometry following microwave assisted acid/peroxide digestion. The aluminium content of ready-to-drink formulas ranged from 49.9 (33.7) to 1956.3 (111.0) μg/L. The most heavily contaminated products were those designed as nutritional supplements for infants struggling to gain weight. The aluminium content of powdered formulas ranged from 0.27 (0.04) to 3.27 (0.19) μg/g. The most heavily contaminated products tended to be those addressing allergies and intolerance. Prescription infant formulas are contaminated with aluminium. Ready-made formulas available as nutritional supplements to aid infant growth contained some of the highest concentrations of aluminium in infant formulas measured in our laboratory. However, a number of prescription infant formulas contained the lowest concentrations of aluminium yet measured in our laboratory. These higher cost specialist preparations demonstrate that the contamination of infant formulas by aluminium is not inevitable. They represent what is achievable should manufacturers wish to address the threat posed to health through infant exposure to aluminium.

Association between concentrations of barium and aluminum in placental tissues and risk for orofacial clefts

Natural exposure to and increasing use of barium and aluminum in various products, such as plastics, rubber, and food additives, raise concerns for their potential health impacts on pregnant women and vulnerable fetuses. We investigated whether there are associations between barium and aluminum concentrations in placental tissues and the risk for orofacial clefts (OFCs) in offspring. In this case-control study, we recruited 103 women with OFC-affected pregnancies and 206 women who delivered healthy newborns. Concentrations of barium and aluminum in placental tissues were measured using inductively coupled plasma-mass spectrometry. Information on maternal sociodemographic characteristics and diet was collected via face-to-face interviews using a structured questionnaire. Aluminum concentrations in placental tissues were not associated with OFC risk. However, a higher concentration of barium in placental tissues was associated with an increased risk for OFCs, with an adjusted odds ratio (OR) of 2.42 (95% confidence interval [95% CI] 1.34-4.40) for total cleft lip with or without cleft palate (CL ± P), and 1.90 (95% CI 1.03-3.50) for isolated CL ± P. There was a positive dose-response relationship between placental barium concentrations and OFC risk. Maternal exposure to barium may increase the risk for OFCs in offspring.

Prenatal Exposure to Aluminum and Status of Selected Essential Trace Elements in Rural South African Women at Delivery

This study sought to evaluate the in utero exposure to aluminum and status of selected trace elements in South African women at delivery since aluminum is known to be toxic in all developmental stages even at low concentrations. Serum aluminum was negatively correlated with aluminum in urine, both uncorrected and corrected for creatinine, which suggests the retention of aluminum in body stores. Serum copper and zinc levels were found to be high in this study population. Serum copper levels were negatively correlated with aluminum in serum (β = -0.095; p = 0.05). There was a marginal negative correlation between aluminum levels in serum and manganese levels in whole blood (β = -0.087; p = 0.08). Copper levels in maternal serum were negatively correlated with birth weight and the length of neonates. There were a number of positive correlations between maternal characteristics and birth outcomes. Mothers who consumed root vegetables frequently appeared to be protected from aluminum retention and increased body burden since their serum aluminum levels were found to be significantly lower. The findings of the current study can be used as a baseline for further research on aluminum exposure and its associated interactions and outcomes in vulnerable populations.

Heavy metal contamination of prenatal vitamins

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Toxic elements are found in prenatal vitamins with lead at unacceptable levels in more than half of the products tested.

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Arsenic is also found in some products at unsafe levels.

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Thallium is present at levels in some products that are not acceptable.

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Some products have very low level, which are safer, and recommendations are made to have industry (self regulatory) and government oversight to have the least contamination of prenatal vitamins.

Prenatal vitamins are often consumed daily during gestation and postnatally for up to 18–24 months with the belief that supplementation achieves better outcomes. Detrimental effects of gestational exposure to adverse chemical agents are gathering increasing attention. This study was designed to assess toxic element contamination in prenatal supplements.

Twenty-six commonly used prenatal vitamin brands including one prescription brand were collected from Canadian health-food outlets and pharmacies, and tested for toxic element contamination. Results were compared to established endpoints.

All samples contained Lead with average amounts being (0.535 μgm), 20/51 samples exceeded established standards for lead toxicity (0.50 μgm/day), with one sample yielding 4. μgm/day. Three samples registered inorganic arsenic levels above acceptable limits. Cadmium levels did not exceed current standards. Toxic elements such as Aluminum, Nickel, Titanium and Thallium were detected in all samples.

Cumulative intake of prenatal supplement over many months may constitute a significant source of toxic element exposure to the mother and offspring. With several samples exceeding known standards for gestational toxic element exposure, guidelines for routine monitoring and reporting are required. In keeping with recommendations from the International Federation of Obstetrics and Gynecology, industry regulation would be welcomed to protect expectant mothers and their vulnerable offspring.

Mineral Homeostasis and Effects on Bone Mineralization in the Preterm Neonate

Most bone formation and mineralization occurs late in gestation. Accretion of adequate minerals is a key element of this process and is often interrupted through preterm birth. In utero, mineral transport is accomplished via active transport across the placenta and does not require fetal hormone input. Postnatal mineral homeostasis requires a balance of actions of parathyroid hormone, calcitonin, and vitamin D on target organs. Preterm birth, asphyxia, acidosis, and prolonged parenteral nutrition increase the risk of mineral imbalance and metabolic bone disease (MBD). Aggressive postnatal nutrition is key to preventing and treating MBD in preterm infants.

Gut: An underestimated target organ for Aluminum

Since World War II, several factors such as an impressive industrial growth, an enhanced environmental bioavailability and intensified food consumption have contributed to a significant amplification of human exposure to aluminum. Aluminum is particularly present in food, beverages, some drugs and airbone dust. In our food, aluminum is superimposed via additives and cooking utensils. Therefore, the tolerable intake of aluminum is exceeded for a significant part of the world population, especially in children who are more vulnerable to toxic effects of pollutants than adults. Faced with this oral aluminum influx, intestinal tract is an essential barrier, especially as 38% of ingested aluminum accumulates at the intestinal mucosa. Although still poorly documented to date, the impact of oral exposure to aluminum in conditions relevant to real human exposure appears to be deleterious for gut homeostasis. Aluminum ingestion affects the regulation of the permeability, the microflora and the immune function of intestine. Nowadays, several arguments are consistent with an involvement of aluminum as an environmental risk factor for inflammatory bowel diseases.

Association between maternal aluminum exposure and the risk of congenital heart defects in offspring

BACKGROUND

Aluminum (Al) is the third most common element in the earth' s crust and has been reported to be teratogenic. However, there is lack of understanding about the association between maternal aluminum exposure and the risks of birth defects such as congenital heart defects (CHDs).

METHODS

A multi-center, hospital-based case-control study was performed at four maternal and child tertiary hospitals in China. A total of 223 cases with CHDs and 223 controls without any abnormalities were recruited according to the inclusion and matching criteria. Hair samples were prepared and measured by inductively coupled plasma mass spectrometry (ICP-MS). The correlation between CHDs and maternal aluminum concentrations was estimated by a 1:1 conditional logistic regression.

RESULTS

The geometric mean and median of hair aluminum levels in isolated or multiple CHD cases was significantly higher than in controls (p < 0.05). A significant association was found between increased hair aluminum concentrations and the risk of total CHDs in offspring (adjusted odds ration [aOR], 2.32; 95% confidence interval [CI], 1.72-3.13), especially in some subtypes of CHDs, such as septal defects (aOR, 2.17; 95% CI, 1.15-4.10), conotruncal defects (aOR, 5.42; 95%CI, 2.43-12.10), and right ventricular outflow track obstruction (aOR, 2.43; 95% CI, 1.08-5.44). However, there was no statistically significant association with left ventricular outflow track obstruction (aOR, 1.66; 95% CI, 0.95-2.88).

CONCLUSION

A high maternal aluminum concentration may significantly increase the risk of delivering a child with a CHD, such as a septal defect, conotruncal heart defect and right-side obstruction.

Advax™, a novel microcrystalline polysaccharide particle engineered from delta inulin, provides robust adjuvant potency together with tolerability and safety

There is an ongoing need for new adjuvants to facilitate development of vaccines against HIV, tuberculosis, malaria and cancer, amongst many others. Unfortunately, the most potent adjuvants are often associated with toxicity and safety issues. Inulin, a plant-derived polysaccharide, has no immunological activity in its native soluble form but when crystallized into a stable microcrystalline particulate from (delta inulin) acquires potent adjuvant activity. Delta inulin has been shown to enhance humoral and cellular immune responses against a broad range of co-administered viral, bacterial, parasitic and toxin antigens. Inulin normally crystallizes as large heterogeneous particles with a broad size distribution and variable solubility temperatures. To ensure reproducible delta inulin particles with a consistent size distribution and temperature of solubility, a current Good Manufacturing Practice (cGMP) process was designed to produce Advax™ adjuvant. In its cCMP form, Advax™ adjuvant has proved successful in human trials of vaccines against seasonal and pandemic influenza, hepatitis B and insect sting anaphylaxis, enhancing antibody and T-cell responses while being safe and well tolerated. Advax™ adjuvant represents a novel human adjuvant that enhances both humoral and cellular immunity. This review describes the discovery and development of Advax™ adjuvant and research into its unique mechanism of action.

Comparative Safety of Vaccine Adjuvants: A Summary of Current Evidence and Future Needs

Use of highly pure antigens to improve vaccine safety has led to reduced vaccine immunogenicity and efficacy. This has led to the need to use adjuvants to improve vaccine immunogenicity. The ideal adjuvant should maximize vaccine immunogenicity without compromising tolerability or safety. Unfortunately, adjuvant research has lagged behind other vaccine areas such as antigen discovery, with the consequence that only a very limited number of adjuvants based on aluminium salts, monophosphoryl lipid A and oil emulsions are currently approved for human use. Recent strategic initiatives to support adjuvant development by the National Institutes of Health should translate into greater adjuvant choices in the future. Mechanistic studies have been valuable for better understanding of adjuvant action, but mechanisms of adjuvant toxicity are less well understood. The inflammatory or danger-signal model of adjuvant action implies that increased vaccine reactogenicity is the inevitable price for improved immunogenicity. Hence, adjuvant reactogenicity may be avoidable only if it is possible to separate inflammation from adjuvant action. The biggest remaining challenge in the adjuvant field is to decipher the potential relationship between adjuvants and rare vaccine adverse reactions, such as narcolepsy, macrophagic myofasciitis or Alzheimer's disease. While existing adjuvants based on aluminium salts have a strong safety record, there are ongoing needs for new adjuvants and more intensive research into adjuvants and their effects.

Non-human primate and rodent embryonic stem cells are differentially sensitive to embryotoxic compounds

Many industrial chemicals and their respective by-products need to be comprehensively evaluated for toxicity using reliable and efficient assays. In terms of teratogenicity evaluations, the murine-based embryonic stem cell test (EST) offers a promising solution to screen for multiple tissue endpoints. However, use of a mouse model in the EST can yield only a limited understanding of human development, anatomy, and physiology. Non-human primate or human in vitro models have been suggested to be a pharmacologically and pathophysiologically desirable alternative to murine in vitro models. Here, we comparatively evaluated the sensitivity of embryonic stem cells (ESCs) of a non-human primate to skeletal teratogens with mouse ESCs hypothesizing that inclusion of non-human primate cells in in vitro tests would increase the reliability of safety predictions for humans.

First, osteogenic capacity was compared between ESCs from the mouse and a New World monkey, the common marmoset. Then, cells were treated with compounds that have been previously reported to induce bone teratogenicity. Calcification and MTT assays evaluated effects on osteogenesis and cell viability, respectively. Our data indicated that marmoset ESCs responded differently than mouse ESCs in such embryotoxicity screens with no obvious dependency on chemical or compound classes and thus suggest that embryotoxicity screening results could be affected by species-driven response variation. In addition, ESCs derived from rhesus monkey, an Old World monkey, and phylogenetically closer to humans than the marmoset, were observed to respond differently to test compounds than marmoset ESCs. Together these results indicate that there are significant differences in the responses of non-human primate and mouse ESC to embryotoxic agents.

Systematic review of potential health risks posed by pharmaceutical, occupational and consumer exposures to metallic and nanoscale aluminum, aluminum oxides, aluminum hydroxide and its soluble salts

Abstract Aluminum (Al) is a ubiquitous substance encountered both naturally (as the third most abundant element) and intentionally (used in water, foods, pharmaceuticals, and vaccines); it is also present in ambient and occupational airborne particulates. Existing data underscore the importance of Al physical and chemical forms in relation to its uptake, accumulation, and systemic bioavailability. The present review represents a systematic examination of the peer-reviewed literature on the adverse health effects of Al materials published since a previous critical evaluation compiled by Krewski et al. (2007) . Challenges encountered in carrying out the present review reflected the experimental use of different physical and chemical Al forms, different routes of administration, and different target organs in relation to the magnitude, frequency, and duration of exposure. Wide variations in diet can result in Al intakes that are often higher than the World Health Organization provisional tolerable weekly intake (PTWI), which is based on studies with Al citrate. Comparing daily dietary Al exposures on the basis of "total Al"assumes that gastrointestinal bioavailability for all dietary Al forms is equivalent to that for Al citrate, an approach that requires validation. Current occupational exposure limits (OELs) for identical Al substances vary as much as 15-fold. The toxicity of different Al forms depends in large measure on their physical behavior and relative solubility in water. The toxicity of soluble Al forms depends upon the delivered dose of Al(+3) to target tissues. Trivalent Al reacts with water to produce bidentate superoxide coordination spheres [Al(O2)(H2O4)(+2) and Al(H2O)6 (+3)] that after complexation with O2(•-), generate Al superoxides [Al(O2(•))](H2O5)](+2). Semireduced AlO2(•) radicals deplete mitochondrial Fe and promote generation of H2O2, O2 (•-) and OH(•). Thus, it is the Al(+3)-induced formation of oxygen radicals that accounts for the oxidative damage that leads to intrinsic apoptosis. In contrast, the toxicity of the insoluble Al oxides depends primarily on their behavior as particulates. Aluminum has been held responsible for human morbidity and mortality, but there is no consistent and convincing evidence to associate the Al found in food and drinking water at the doses and chemical forms presently consumed by people living in North America and Western Europe with increased risk for Alzheimer's disease (AD). Neither is there clear evidence to show use of Al-containing underarm antiperspirants or cosmetics increases the risk of AD or breast cancer. Metallic Al, its oxides, and common Al salts have not been shown to be either genotoxic or carcinogenic. Aluminum exposures during neonatal and pediatric parenteral nutrition (PN) can impair bone mineralization and delay neurological development. Adverse effects to vaccines with Al adjuvants have occurred; however, recent controlled trials found that the immunologic response to certain vaccines with Al adjuvants was no greater, and in some cases less than, that after identical vaccination without Al adjuvants. The scientific literature on the adverse health effects of Al is extensive. Health risk assessments for Al must take into account individual co-factors (e.g., age, renal function, diet, gastric pH). Conclusions from the current review point to the need for refinement of the PTWI, reduction of Al contamination in PN solutions, justification for routine addition of Al to vaccines, and harmonization of OELs for Al substances.