Teratogenicity of depleted uranium aerosols: a review from an epidemiological perspective

Enhanced uranium sequestration through selenite-modified nano-chitosan loaded with melatonin: Facilitating U(IV) conversion

The combined chemotoxicity and radiotoxicity associated with uranium, utilized in nuclear industry and military applications, poses significant threats to human health. Among uranium pollutants, uranyl is particularly concerning due to its high absorptivity and potent nephrotoxicity in its + 6 valence state. Here, we have serendipitously found Na2SeO3 facilitates the conversion of U(VI) to U(IV) precipitates. A novel approach involving nano-chitosan loaded internally with melatonin and externally modified with selenite (NPs Cs-Se/MEL) was introduced. This modification not only enhances the conversion of U(VI) to U(IV) but also preserves the spherical nanostructure and specific surface area, leading to increased adsorption of U(VI) compared to unmodified samples. Selenite modification improves lysosomal delivery in HEK-293 T cells and kidney distribution of the nanoparticles. Furthermore, NPs Cs-Se/MEL demonstrated a heightened uranium concentration in urine and exhibited remarkable efficiency in uranium removal, resulting in a reduction of uranium deposition in serum, kidneys, and femurs by up to 52.02 %, 46.79 %, and 71.04 %, respectively. Importantly, NPs Cs-Se/MEL can be excreted directly from the kidneys into urine when carrying uranium. The results presented a novel mechanism for uranium adsorption, making selenium-containing nano-materials attractive for uranium sequestration and detoxification.

Exploration of Teratogenic and Genotoxic Effects on Model Organism Drosophila melanogaster

Drosophila melanogaster is one of the crucial in vivo models in terms of analyzing the toxicity of various unknown chemicals. Every part of the fly serves as a model in metabolic and therapeutic approaches. Genotoxic and teratogenic compounds are exposed to Drosophila through the oral route. Further, the toxicity of genotoxic compounds is analyzed in Drosophila's gut, hemolymph, and phenotype. The toxicity of teratogen compounds is also analyzed using a Drosophila embryo. The current chapter summarizes several techniques that are used to detect the genotoxicity and teratogenicity of any unknown compound in this model.

US drinking water quality: exposure risk profiles for seven legacy and emerging contaminants

BACKGROUND

Advances in drinking water infrastructure and treatment throughout the 20th and early 21st century dramatically improved water reliability and quality in the United States (US) and other parts of the world. However, numerous chemical contaminants from a range of anthropogenic and natural sources continue to pose chronic health concerns, even in countries with established drinking water regulations, such as the US.

OBJECTIVE/METHODS

In this review, we summarize exposure risk profiles and health effects for seven legacy and emerging drinking water contaminants or contaminant groups: arsenic, disinfection by-products, fracking-related substances, lead, nitrate, per- and polyfluorinated alkyl substances (PFAS) and uranium. We begin with an overview of US public water systems, and US and global drinking water regulation. We end with a summary of cross-cutting challenges that burden US drinking water systems: aging and deteriorated water infrastructure, vulnerabilities for children in school and childcare facilities, climate change, disparities in access to safe and reliable drinking water, uneven enforcement of drinking water standards, inadequate health assessments, large numbers of chemicals within a class, a preponderance of small water systems, and issues facing US Indigenous communities.

RESULTS

Research and data on US drinking water contamination show that exposure profiles, health risks, and water quality reliability issues vary widely across populations, geographically and by contaminant. Factors include water source, local and regional features, aging water infrastructure, industrial or commercial activities, and social determinants. Understanding the risk profiles of different drinking water contaminants is necessary for anticipating local and general problems, ascertaining the state of drinking water resources, and developing mitigation strategies.

IMPACT STATEMENT

Drinking water contamination is widespread, even in the US. Exposure risk profiles vary by contaminant. Understanding the risk profiles of different drinking water contaminants is necessary for anticipating local and general public health problems, ascertaining the state of drinking water resources, and developing mitigation strategies.

Bacillus sp. strain MRS-1: A potential candidate for uranyl biosorption from uranyl polluted sites

The uranyl tolerance of a metal-resistant Bacillus sp. strain MRS-1, was determined in this current study. This was done due to a rise in anthropogenic activities, such as the production of uranium-based nuclear energy, which contributes to environmental degradation and poses risks to ecosystems and human health. The purpose of the research was to find effective strategies for uranium removal to minimize the contamination. In this paper, the biosorption of uranyl was investigated by batch tests. Bacteria could continue to multiply up to 350 ppm uranyl concentrations, however this growth was suppressed at 400 ppm, that generally accepted as the minimum concentration for bacterial growth inhibition. The optimal conditions for uranyl biosorption were pH 7, 20 °C, and a contact duration of 30 min with living bacteria. According to the findings of an investigation that used isotherm and kinetics models (Langmuir, Freundlich and pseudo second order), Bacillus sp. strain MRS-1 biosorption seemed to be dependent on monolayer adsorption as well as certain functional groups that had a strong affinity for uranyl confirmed by Fourier Transform Infrared Spectroscopy (FTIR) analysis. The shifts/sharping of peaks (1081-3304 cm-1) were prominent in treated samples compared to control one. These functional groups could be hydroxyl, amino, and carboxyl. Our findings showed that Bacillus sp. strain MRS-1 has an elevated uranyl biosorption ability, with 24.5 mg/g being achieved. This indicates its potential as a powerful biosorbent for dealing with uranium contamination in drinking water sources and represents a breakthrough in the cleanup of contaminated ecosystems.

Environmental and health hazards of military metal pollution

An increasing body of literature has demonstrated that armed conflicts and military activity may contribute to environmental pollution with metals, although the existing data are inconsistent. Therefore, in this paper, we discuss potential sources of military-related metal emissions, environmental metal contamination, as well as routes of metal exposure and their health hazards in relation to military activities. Emission of metals into the environment upon military activity occurs from weapon residues containing high levels of particles containing lead (Pb; leaded ammunition), copper (Cu; unleaded), and depleted uranium (DU). As a consequence, military activity results in soil contamination with Pb and Cu, as well as other metals including Cd, Sb, Cr, Ni, Zn, with subsequent metal translocation to water, thus increasing the risk of human exposure. Biomonitoring studies have demonstrated increased accumulation of metals in plants, invertebrates, and vertebrate species (fish, birds, mammals). Correspondingly, military activity is associated with human metal exposure that results from inhalation or ingestion of released particles, as well as injuries with subsequent metal release from embedded fragments. It is also notable that local metal accumulation following military injury may occur even without detectable fragments. Nonetheless, data on health effects of military-related metal exposures have yet to be systematized. The existing data demonstrate adverse neurological, cardiovascular, and reproductive outcomes in exposed military personnel. Moreover, military-related metal exposures also result in adverse neurodevelopmental outcome in children living within adulterated territories. Experimental in vivo and in vitro studies also demonstrated toxic effects of specific metals as well as widely used metal alloys, although laboratory data report much wider spectrum of adverse effects as compared to epidemiological studies. Therefore, further epidemiological, biomonitoring and laboratory studies are required to better characterize military-related metal exposures and their underlying mechanisms of their adverse toxic effects.

VALIDATED MEASUREMENT OF URANIUM IN A HUMAN URINE STANDARD REFERENCE MATERIAL BY ICP-MS WITH THE STANDARD ADDITION METHOD

The Urine Analysis Laboratory of the Korea Atomic Energy Research Institute has developed an in vitro method for measuring uranium in spot urine samples using inductively coupled plasma-mass spectrometry (ICP-MS) with microwave-assisted digestion and standard addition. To validate this procedure, the frozen human urine standard reference material (SRM 2668), such as uranium and creatinine, were analyzed. To overcome the matrix effect and thereby obtain precise measurement data, the standard addition method with extrapolation of four additional points was applied. The measured values for uranium in the SRM were within the acceptable margin of error. The results were compared and evaluated with respect to the American National Standards Institute and Heath Physics Society (ANSI/HPS) N13.30 and International Organization for Standardization 28218 standards. The relative precision (SBr), relative bias (Br), and root-mean-square error values were within the acceptable ranges for the SRM.

Weaponised uranium and adverse health outcomes in Iraq: a systematic review

Background

The US military first deployed depleted uranium (DU) weapons in Iraq during the Gulf War in 1990 and in the 2003 invasion of Iraq. Research into the health impacts of DU has been mired in debate and controversy. Research funded by the US government has denied the health risks posed by DU to the Iraqi population, while opponents have claimed that DU is responsible for increased rates of birth defects and cancers in Iraq. Others assert that the public health impacts of DU weapons remain uncertain. This systematic review identified, appraised and synthesised all human observational studies assessing adverse health outcomes associated with DU exposure among the Iraqi population. To our knowledge, no systematic review has been conducted on the topic previously.

Methods

We searched 11 electronic databases for human observational studies published between 1990 and 2020 that measured association between exposure to weaponised uranium and health outcomes (including cancer, birth defects, immune system function and mortality) among the Iraqi population. We assessed risk of bias using the Navigation Guide’s risk of bias tool and rated certainty of the evidence using the Grading of Recommendations, Assessment, Development and Evaluations approach (PROSPERO: CRD42018108225).

Results

Our searches identified 2601 records, of which 28 met our inclusion criteria. We identified five additional eligible reports from other sources. Two articles reported the results of multiple relevant studies; our final set included 33 articles reporting on 36 eligible studies. Most studies (n=30, 83%) reported a positive association between uranium exposure and adverse health outcomes. However, we found that the reviewed body of evidence suffers from a high risk of bias.

Conclusion

The available evidence suggests possible associations between exposure to depleted uranium and adverse health outcomes among the Iraqi population. More primary research and the release of missing data are needed to design meaningful health and policy interventions in Iraq.

Folic Acid Fortification Prevents Morphological and Behavioral Consequences of X-Ray Exposure During Neurulation

Previous studies suggested a causal link between pre-natal exposure to ionizing radiation and birth defects such as microphthalmos and exencephaly. In mice, these defects arise primarily after high-dose X-irradiation during early neurulation. However, the impact of sublethal (low) X-ray doses during this early developmental time window on adult behavior and morphology of central nervous system structures is not known. In addition, the efficacy of folic acid (FA) in preventing radiation-induced birth defects and persistent radiation-induced anomalies has remained unexplored. To assess the efficacy of FA in preventing radiation-induced defects, pregnant C57BL6/J mice were X-irradiated at embryonic day (E)7.5 and were fed FA-fortified food. FA partially prevented radiation-induced (1.0 Gy) anophthalmos, exencephaly and gastroschisis at E18, and reduced the number of pre-natal deaths, fetal weight loss and defects in the cervical vertebrae resulting from irradiation. Furthermore, FA food fortification counteracted radiation-induced impairments in vision and olfaction, which were evidenced after exposure to doses ≥0.1 Gy. These findings coincided with the observation of a reduction in thickness of the retinal ganglion cell and nerve fiber layer, and a decreased axial length of the eye following exposure to 0.5 Gy. Finally, MRI studies revealed a volumetric decrease of the hippocampus, striatum, thalamus, midbrain and pons following 0.5 Gy irradiation, which could be partially ameliorated after FA food fortification. Altogether, our study is the first to offer detailed insights into the long-term consequences of X-ray exposure during neurulation, and supports the use of FA as a radioprotectant and antiteratogen to counter the detrimental effects of X-ray exposure during this crucial period of gestation.

A Review of Uranium-Induced Reproductive Toxicity

As a heavy metal nuclear fuel, uranium is used in various civil and military projects, resulting in environmental pollution. Uranium can enter the body through the mouth, nose and skin, threatening human health. The reproductive organs are sensitive to uranium. For certain exposure times, doses and modes, uranium can produce toxic effects on the reproductive organs. The reproductive toxicity of uranium can be produced through different mechanisms of action, such as changing the level of sex hormones in the body, disrupting the expression of genes or proteins related to reproduction and causing oxidative stress and inflammation. Uranium thus can cause toxic effects to the reproductive system, leading to histopathological changes and decreased conception rates, and may damage the health of the body. This paper reviews the research progress on uranium reproductive toxicity in recent years and indicates a direction for future research on uranium reproductive toxicity and its mechanisms.

Living near an active U.S. military base in Iraq is associated with significantly higher hair thorium and increased likelihood of congenital anomalies in infants and children

In Iraq, war contamination is the result of dispensed bombs, bullets, detonation of chemical and conventional weapons, and burn-pit emissions by US bases. Increases in congenital anomalies were reported from Iraqi cities post-2003. These cities were heavily bombed and encircled by US bases with burn-pits. Thorium is a radioactive compound and a direct depleted-uranium decay-product. Radioactive materials, including depleted uranium, are routinely stored in US bases and they have been shown to leak into the environment. We conducted a case-control study to investigate associations of residential proximity to Tallil Air Base, a US military base near Nasiriyah, as well as levels of uranium and thorium in hair and deciduous teeth with congenital anomalies. The study was based on a sample of 19 cases and 10 controls who were recruited during late Summer and early Fall of 2016. We developed mixed effects logistic regression models with village as the random effect, congenital anomaly as the outcome and distance to the US base and hair metal levels (one at a time) as the predictor variable, controlling for child's age, sex and paternal education. We also explored the mediation of the association between proximity to the base and congenital anomalies by hair metal levels. We found an inverse association between distance to Tallil Air Base and risk of congenital anomalies and hair levels of thorium and uranium. The results of our mediation analyses were less conclusive. Larger studies are necessary to understand the scope of war contamination and its impact on congenital anomalies in Iraq.

Levels of uranium and thorium in maternal scalp hair and risk of orofacial clefts in offspring

Uranium and thorium are common radioactive elements that exist in the environment. However, few environmental epidemiological studies have focused on their possible effects on congenital malformations. Here, we explored the association between uranium and thorium concentrations in maternal scalp hair grown from 3 months before to 3 months after conception, namely during the periconceptional period and the risk of orofacial clefts (OFCs) in offspring. Our study included 153 women whose pregnancies were affected by OFCs (cases) and 601 women who delivered infants without birth defects (controls) from four provinces in China. Face-to-face interviews were used to collect sociodemographic characteristics with a structured questionnaire. Concentrations of uranium and thorium in maternal scalp hair grown during the periconceptional period were detected using inductively coupled plasma-mass spectrometry. The risk of OFCs in association with higher concentrations of the two radioactive elements was estimated using odds ratios (ORs) and 95% confidence intervals (CIs) while adjusting for potential confounding factors. The levels of uranium and thorium in maternal hair were in agreement with the published literature. After adjusting for several confounders, the ORs of thorium in the highest, upper, and lower quartile versus the lowest quartile were 2.63 (95% CI, 1.41-4.92), 1.98 (95% CI, 1.03-3.79), and 2.73 (95% CI, 1.46-5.12), respectively. No association was found between levels of uranium and the risk of OFCs. Maternal periconceptional exposure to thorium may be a risk factor for OFCs in offspring.

Human exposure to uranium in South African gold mining areas using barber-based hair sampling

Uranium (U) measurements in water, soil, and food related to gold mining activities in populated areas in Gauteng Province, South Africa, suggest the possibility of exposure levels that may lead to adverse health consequences, including cancer. Theoretical considerations on pathways of human uptake of significant exposures are plausible, but few data on directly measured human exposure are available. A cross-sectional study was conducted using human measurements to compare U levels with other settings around the globe (based on literature review), to explore potential exposure variability within the province, and to test the feasibility of recruiting subjects partially coming from vulnerable and difficult-to-reach populations. Wards of potentially high (HE) and low exposure (LE) were identified. Composite hair samples representing the respective local populations were collected from regular customers of selected barber shops over a period of 1-2 months. A total of 70 U concentrations were determined in 27 composite samples from 1332 individuals. U concentrations ranged from 31 μg/kg to 2524 μg/kg, with an arithmetic mean of 192 μg/kg (standard deviation, 310 μg/kg) and a median of 122 μg/kg. Although HE wards collectively showed higher U levels than LE wards (184 vs 134 μg/kg), differences were smaller than expected. In conclusion, detected U levels were higher than those from most other surveys of the general public. The barber-based approach was an efficient hair collection approach. Composite hair samples are not recommended, due to technical challenges in measuring U, and individual hair samples are needed in follow-up studies to determine predictors of exposure.

Hospital centered surveillance of births in Gaza, Palestine, 2011-2017 and heavy metal contamination of the mothers reveals long-term impact of wars

Prevalence of preterm, low birth weight and birth defects increased significantly since 2011 in Gaza, Palestine. No change in known co-factors of reproductive health justified this rise. Two military attacks in 2012 and 2014 introduced novel risk factors for outcomes at birth: contamination by teratogenic and carcinogenic heavy metals weapon-remnants, ongoing impoverishment, and impaired rehabilitation of waste management. It was previously shown that mothers exposed to military attacks had higher metal load than those unexposed and mother's heavy metals trans-pass placenta. We investigated association in time of heavy metal contamination and reproductive health using hospital-based surveillance (2011-2016-2017) of births, accompanied by assessment in 2016 of metal load in mother and newborn hair. Mother's housing proximal to unmanaged waste predicted preterm birth and birth defects, and these women had highest load of heavy metals. Poor diet predicted low birth weight. Circumstances prevent investigation of heavy metals molecular impact(s) during fetal development.

A Review on Toxicodynamics of Depleted Uranium

Depleted uranium (DU) is an important by product in uranium enrichment process. Due to its applications in civilian and also military activity, DU emerged as environmental pollutant. The exposure to DU can occur via external or internal pathways. In external exposure, mainly beta radiation from the decay products contributes to DU toxicity. Internal exposure to DU is more important and can occur through ingestion of DU-contaminated water and food and inhalation of DU aerosols. There is limited information about health effects and mechanism of DU after environmental exposure. Kidney is reported as the main target organ for the chemical toxicity of this metal that was reported in Persian Gulf syndrome. Alterations in behavior, some neurologic adverse effects, immunotoxicity, embryo-toxicity and hepatotoxicity were observed in chronic exposure to DU. Also, the increased risk of cancer was revealed in epidemiological and experimental studies. Several mechanisms were suggested for DU toxicity such as oxidative stress, mitochondrial toxicity and inflammation. In fact, uranium like other toxic heavy metals can induce oxidative damage and apoptosis via mitochondrial pathway and inflammatory response. In this review, we have discussed the kinetic of DU including source and exposure pathway. In addition, the health effects of DU and also its toxic mechanism have been highlighted.

A survey of uranium levels in urine and hair of people living in a coal mining area in Yili, Xinjiang, China

Recent reports have drawn attention to the uranium contamination arising from coal mining activities in the Yili region of Xinjiang, China due to the mixed distribution of uranium and coal mines, and some of the coal mines being associated with a high uranium content. In this study, we have collected water samples, solid samples such as soil, mud, coal, and coal ash, and hair and urine samples from local populations in order to evaluate the uranium level in this environment and its implications for humans in this high uranium coal mining area. Our results showed that uranium concentrations were 8.71-10.91 μg L^-1 in underground water, whereas lower levels of uranium occurred in river water. Among the solid samples, coal ash contained fairly high concentrations of uranium (33.1 μg g^-1) due to enrichment from coal burning. In addition, uranium levels in the other solid samples were around 2.8 μg g^-1 (the Earth's average background value). Uranium concentrations in hair and urine samples were 22.2-634.5 ng g^-1 (mean: 156.2 ng g^-1) and 8.44-761.6 ng L^-1 (mean: 202.6 ng L^-1), respectively, which are significantly higher than reference values reported for unexposed subjects in other areas. Therefore, these results indicate that people living in this coal mining area have been subjected to uranium exposure for long periods of time.

Asymmetrically enlarged parietal foramina in a rare case of Goldenhar syndrome with a possible etiopathogenesis

Goldenhar´s syndrome (GS) also known as oculo-auriculo-vertebral spectrum (OAVS) is a relatively rare condition. GS is of multifactorial etiology that includes environmental and/or genetic factors, in addition to teratogens that disturb the blastogenesis. A 5-year-old girl from Saudi Arabia, was a member of dizygotic twins conceived by assisted reproductive technology (ART), and born with features of GS. She had asymmetrical face, cleft lip and palate, right microphthalmia and microtia. Radiological imaging showed right maxillary and mandibular bone hypoplasia, asymmetrically enlarged parietal foramina, a persistent midline occipital foramen, abnormal bone arising from occipital bone, extending along tentorium cerebelli, and a lipoma at the right tentorium cerebelli. A rudimentary right eye with dermoid cyst and pseudotumor as well as bilateral atresia of external auditory canals were present. Karyotyping was normal. ART and the risk of manipulation of ovum/embryo, was shown to be associated with multiple gestation and an increased risk of major birth defects. Given that our patient was from Eastern-province close to the South of Iraq, where Gulf wars took place and the reported incidence of birth defects, including orofacial malformation, jumped there to about seven-folds, after war, thus, environmental contamination, and the possible teratogenic effect of depleted uranium could not be excluded. In conclusion, our case of GS, disclosed a rare radiological finding in calvarial anatomy, and asserted that, careful clinical evaluation is recommended in cases of GS. ART fertilization risk along with the possible parental environmental exposure were regarded as the potential cooperators of multifactorial etiology in our case.

(Dis)connectivities in wartime: The therapeutic geographies of Iraqi healthcare-seeking in Lebanon

The proliferation of conflicts across borders of Middle Eastern States has transformed the landscapes of health and healthcare across the region. In the case of Iraq, state healthcare has collapsed under the strain of protracted conflicts. Meanwhile, Lebanon's post-war healthcare system is booming, and becoming more privatised. In this paper, we build on an ethnographic study on the movements and experiences of Iraqi patients in Lebanon to show how one of the consequences of war is the rise of alternative forms of healthcare-seeking practices and survival strategies - a therapeutic geography that is embedded in regional economies and geopolitical relations and reconfigurations. We argue for the need to reimagine the disconnectivity and connectivity of healthcare systems under war and conflict as grounded in the empirical realities and experiences of mobility in the Middle East.

A cross sectional study of the relationship between the exposure of pregnant women to military attacks in 2014 in Gaza and the load of heavy metal contaminants in the hair of mothers and newborns

OBJECTIVE

Metal contamination of humans in war areas has rarely been investigated. Weaponry's heavy metals become environmentally stable war remnants and accumulate in living things. They also pose health risks in terms of prenatal intake, with potential long term risks for reproductive and children's health. We studied the contribution of military attacks to the load of 23 metals in the hair of Palestinian women in the Gaza Strip, who were pregnant at the time of the military attacks in 2014, and their newborns. We compared the metal load in the mothers with values for adult hair from outside the war area (RHS) as the reference. We investigated heavy metals trans-passing in utero, and assessed if the heavy metal intake could derive from sources unrelated to the war.

DESIGN

Cross sectional study.

PARTICIPANTS AND SETTING

Cross sectional convenience sample of 502 mothers delivering in the Gaza Strip and their newborns.

MAIN OUTCOME MEASURED

Measure of the load of heavy metals in mother and newborn hair by inductively coupled plasma-mass spectrometry (ICP-MS). Comparison of metal loads with the reference RHS, between groups with different exposures to attacks and house/agriculture chemicals, and between mothers and newborns. Data for birth registry and for exposures to war and other known risk factors were obtained at interview with the mothers. Photographic documentation of damage from military attacks was obtained.

RESULTS

The whole cross sectional convenience sample had a significantly higher load of heavy metals than the reference RHS. Women exposed to military attacks had a significantly higher load of heavy metals than those not exposed; the load in newborns correlated positively with the mothers' load. No significant difference was found between users/non-users of house/agriculture chemicals. No other known confounder was identified.

CONCLUSIONS

High heavy metal loads in mothers, reflected in those of their newborns, were associated with exposure to military attacks, posing a risk of immediate and long term negative outcomes for pregnancy and child health. Surveillance, biomonitoring and further research are recommended. Implications for general and public health are discussed.

Depleted and enriched uranium exposure quantified in former factory workers and local residents of NL Industries, Colonie, NY USA

BACKGROUND

Between 1958 and 1982, NL Industries manufactured components of enriched (EU) and depleted uranium (DU) at a factory in Colonie NY, USA. More than 5 metric tons of DU was deposited as microscopic DU oxide particles on the plant site and surrounding residential community. A prior study involving a small number of individuals (n=23) indicated some residents were exposed to DU and former workers to both DU and EU, most probably through inhalation of aerosol particles.

OBJECTIVES

Our aim was to measure total uranium [U] and the uranium isotope ratios: (234)U/(238)U; (235)U/(238)U; and (236)U/(238)U, in the urine of a cohort of former workers and nearby residents of the NLI factory, to characterize individual exposure to natural uranium (NU), DU, and EU more than 3 decades after production ceased.

METHODS

We conducted a biomonitoring study in a larger cohort of 32 former workers and 99 residents, who may have been exposed during its period of operation, by measuring Total U, NU, DU, and EU in urine using Sector Field Inductively Coupled Plasma - Mass Spectrometry (SF-ICP-MS).

RESULTS

Among workers, 84% were exposed to DU, 9% to EU and DU, and 6% to natural uranium (NU) only. For those exposed to DU, urinary isotopic and [U] compositions result from binary mixing of NU and the DU plant feedstock. Among residents, 8% show evidence of DU exposure, whereas none shows evidence of EU exposure. For residents, the [U] geometric mean is significantly below the value reported for NHANES. There is no significant difference in [U] between exposed and unexposed residents, suggesting that [U] alone is not a reliable indicator of exposure to DU in this group.

CONCLUSIONS

Ninety four percent of workers tested showed evidence of exposure to DU, EU or both, and were still excreting DU and EU decades after leaving the workforce. The study demonstrates the advantage of measuring multiple isotopic ratios (e.g., (236)U/(238)U and (235)U/(238)U) over a single ratio ((235)U/(238)U) in determining sources of uranium exposure.

Human exposure to environmental contaminants and congenital anomalies: a critical review

Congenital anomalies are an important cause of infant mortality and disability. Developmental exposure to environmental contaminants is thought to increase the risk for congenital anomalies. Herein, we describe a critical review of the literature conducted between February and March 2014 yielding 3057 references from which 97 unique relevant articles published from 2003 through 2014 were evaluated. Common congenital anomalies including hypospadias, cryptorchidism, anogenital distance (AGD), congenital heart defects and oral clefts were well represented in the literature whereas other outcomes such as neural tube defects, limb deficiency defects and gastroschisis were rarely described. While definitions used for congenital anomalies and methods of ascertainment were usually consistent across studies, inconsistencies were frequently found in grouping of different congenital heart defects. Despite strong links between some congenital anomalies and parental occupation, these studies are unable to provide clear insight into the specific chemicals responsible owing to lack of direct measures of exposure. In comparison, data are mixed for contaminant exposures at concentrations representative of results from contemporary biomonitoring studies. Of the environmental contaminants studied, the association between phthalate exposures and developmental abnormalities of the male reproductive tract received the greatest attention. Important limitations of the literature studied relate to adequacy of sample size, absence of or weaknesses in exposure assessment methodologies, failure to account for biological plausibility and grouping of congenital anomalies with divergent mechanisms. We conclude that the literature is inadequate at this time to support a conclusion that exposure to environmental contaminants are or are not associated with increased risks for congenital anomalies in the general population.

A new organic-silica based nanocomposite prepared for spectrophotometric determination of uranyl ions

A new organic-silica based nanocomposite has been prepared for uranyl ion (UO₂²⁺) determination based on the absorbance enhancement of tartrazine incorporated copper sodium silicate nanocomposites (T-CSS).

Estimation of the respiratory tract burden resulting from a prolonged inhalation exposure to aerosols of DU, based on the U in a 24-h urine sample taken years after exposure

A procedure is presented to estimate the respiratory tract burden from a prolonged inhalation exposure to particulate matter of depleted uranium, in cases where the rate of deposition is an unknown function. The precise range of possible values is identified. The calculations are based on the amount of depleted uranium measured in a single 24-h urine sample. In order to present an example, a simplified pharmacokinetical model is introduced. The results presented in this article are valid for any pharmacokinetical model represented by homogeneous linear differential equations with constant coefficients and non-zero initial values, and that clearly includes the International Commission on Radiological Protection model. In fact, they are applicable to any monitorable quantity measured over a short period of time, a monitorable quantity with a kinetic that can be described using a structurally similar system of differential equations to one describing these pharmacokinetical models.

Zinc protects human kidney cells from depleted uranium-induced apoptosis

Depleted uranium (DU) is a weak radioactive heavy metal, and zinc (Zn) is an effective antidote to heavy metal poisoning. However, the effect of Zn on DU-induced cytotoxicity and apoptosis is not completely understood. The purpose of this study was to evaluate the effect of Zn on DU-induced cell apoptosis in human kidney cells (HK-2) and explore its molecular mechanism. Pre-treatment with Zn significantly inhibited DU-induced apoptosis. It reduced the formation of reactive oxygen species in the cells, increased the catalase (CAT) and glutathione (GSH) concentrations, suppressed the DU-induced soluble Fas receptor (sFasR) and soluble Fas ligand (sFasL) overexpression, suppressed the release of cytochrome c and apoptosis inhibitor factor (AIF) from mitochondria to cytoplasm, inhibited the activation of caspase-9, caspase-8 and caspase-3, and induced metallothionein (MT) expression. Furthermore, exogenous MT effectively inhibited DU-induced cell apoptosis. In conclusion, mitochondrial and FasR-mediated apoptosis pathways contribute to DU-induced apoptosis in HK-2 cells. Through independent mechanisms, such as indirect antioxidant effects, inhibition of the activation of caspase-9, caspase-8 and caspase-3, and induction of MT expression, Zn inhibits DU-induced apoptosis.

Environmental pollution by depleted uranium in Iraq with special reference to Mosul and possible effects on cancer and birth defect rates

Iraq is suffering from depleted uranium (DU) pollution in many regions and the effects of this may harm public health through poisoning and increased incidence of various cancers and birth defects. DU is a known carcinogenic agent. About 1200 tonnes of ammunition were dropped on Iraq during the Gulf Wars of 1991 and 2003. As a result, contamination occurred in more than 350 sites in Iraq. Currently, Iraqis are facing about 140,000 cases of cancer, with 7000 to 8000 new ones registered each year. In Baghdad cancer incidences per 100,000 population have increased, just as they have also increased in Basra. The overall incidence of breast and lung cancer, Leukaemia and Lymphoma, has doubled even tripled. The situation in Mosul city is similar to other regions. Before the Gulf Wars Mosul had a higher rate of cancer, but the rate of cancer has further increased since the Gulf Wars.

Birth defects in Iraq and the plausibility of environmental exposure: A review

An increased prevalence of birth defects was allegedly reported in Iraq in the post 1991 Gulf War period, which was largely attributed to exposure to depleted uranium used in the war. This has encouraged further research on this particular topic. This paper reviews the published literature and provided evidence concerning birth defects in Iraq to elucidate possible environmental exposure. In addition to published research, this review used some direct observation of birth defects data from Al-Ramadi Maternity and Paediatric Hospital in Al-Anbar Governorate in Iraq from1st July 2000 through 30th June 2002. In addition to depleted uranium other war-related environmental factors have been studied and linked directly or indirectly with the increasing prevalence of birth defects. However, the reviewed studies and the available research evidence do not provide a clear increase in birth defects and a clear indication of a possible environmental exposure including depleted uranium although the country has been facing several environmental challenges since 1980.

Uranium and other contaminants in hair from the parents of children with congenital anomalies in Fallujah, Iraq

BACKGROUND

Recent reports have drawn attention to increases in congenital birth anomalies and cancer in Fallujah Iraq blamed on teratogenic, genetic and genomic stress thought to result from depleted Uranium contamination following the battles in the town in 2004. Contamination of the parents of the children and of the environment by Uranium and other elements was investigated using Inductively Coupled Plasma Mass Spectrometry. Hair samples from 25 fathers and mothers of children diagnosed with congenital anomalies were analysed for Uranium and 51 other elements. Mean ages of the parents was: fathers 29.6 (SD 6.2); mothers: 27.3 (SD 6.8). For a sub-group of 6 women, long locks of hair were analysed for Uranium along the length of the hair to obtain information about historic exposures. Samples of soil and water were also analysed and Uranium isotope ratios determined.

RESULTS

Levels of Ca, Mg, Co, Fe, Mn, V, Zn, Sr, Al, Ba, Bi, Ga, Pb, Hg, Pd and U (for mothers only) were significantly higher than published mean levels in an uncontaminated population in Sweden. In high excess were Ca, Mg, Sr, Al, Bi and Hg. Of these only Hg can be considered as a possible cause of congenital anomaly. Mean levels for Uranium were 0.16 ppm (SD: 0.11) range 0.02 to 0.4, higher in mothers (0.18 ppm SD 0.09) than fathers (0.11 ppm; SD 0.13). The highly unusual non-normal Fallujah distribution mean was significantly higher than literature results for a control population Southern Israel (0.062 ppm) and a non-parametric test (Mann Whitney-Wilcoxon) gave p = 0.016 for this comparison of the distribution. Mean levels in Fallujah were also much higher than the mean of measurements reported from Japan, Brazil, Sweden and Slovenia (0.04 ppm SD 0.02). Soil samples show low concentrations with a mean of 0.76 ppm (SD 0.42) and range 0.1-1.5 ppm; (N = 18). However it may be consistent with levels in drinking water (2.28 μgL-1) which had similar levels to water from wells (2.72 μgL-1) and the river Euphrates (2.24 μgL-1). In a separate study of a sub group of mothers with long hair to investigate historic Uranium excretion the results suggested that levels were much higher in the past. Uranium traces detected in the soil samples and the hair showed slightly enriched isotopic signatures for hair U238/U235 = (135.16 SD 1.45) compared with the natural ratio of 137.88. Soil sample Uranium isotope ratios were determined after extraction and concentration of the Uranium by ion exchange. Results showed statistically significant presence of enriched Uranium with a mean of 129 with SD5.9 (for this determination, the natural Uranium 95% CI was 132.1 < Ratio < 144.1).

CONCLUSIONS

Whilst caution must be exercised about ruling out other possibilities, because none of the elements found in excess are reported to cause congenital diseases and cancer except Uranium, these findings suggest the enriched Uranium exposure is either a primary cause or related to the cause of the congenital anomaly and cancer increases. Questions are thus raised about the characteristics and composition of weapons now being deployed in modern battlefields.

Protective effects of ion-imprinted chitooligosaccharides as uranium-specific chelating agents against the cytotoxicity of depleted uranium in human kidney cells

Occupational internal contamination with depleted uranium (DU) compounds can induce radiological and chemical toxicity, and an effective and specific uranium-chelating agent for clinical use is urgently needed. The purpose of this study was to investigate whether a series of synthesized water-soluble metal-ion-imprinted chitooligosaccharides can be used as uranium-specific chelating agents, because the chitooligosaccharides have excellent heavy metal ion chelation property and the ion-imprinting technology can improve the selective recognition of template ions. DU-poisoned human renal proximal tubule epithelium cells (human kidney 2 cells, HK-2) were used to assess the detoxification of these chitooligosaccharides. The DU-chelating capacity and selectivity of the chitooligosaccharides were determined by inductively coupled plasma-mass spectrometry (ICP-MS). Cell viability, cellular accumulation of DU, membrane damage, DNA damage, and morphological changes in the cellular ultrastructure were examined to assess the detoxification of these chitooligosaccharides. The results showed that the Cu²⁺-imprinted chitooligosaccharides, especially the Cu²⁺-imprinted glutaraldehyde-crosslinked carboxymethyl chitooligosaccharide (Cu-Glu-CMC), chelated DU effectively and specifically, and significantly reduced the loss of cell viability induced by DU and reduced cellular accumulation of DU in a dose-dependent manner, owing to their chelation of DU outside cells and their prevention of DU internalization. The ultrastructure observation clearly showed that Cu-Glu-CMC-chelated-DU precipitates, mostly outside cells, were grouped in significantly larger clusters, and they barely entered the cells by endocytosis or in any other way. Treatment with Cu-Glu-CMC also increased the activity of antioxidant enzymes, and reduced membrane damage and DNA damage induced by DU oxidant injury. Cu-Glu-CMC was more effective than the positive control drug, diethylenetriaminepentaacetic acid (DTPA), in protection of HK-2 cells against DU cytotoxicity, as a result of its chelation of UO₂²⁺ to prevent the DU internalization and its antioxidant activity.

Four polygamous families with congenital birth defects from Fallujah, Iraq

Since 2003, congenital malformations have increased to account for 15% of all births in Fallujah, Iraq. Congenital heart defects have the highest incidence, followed by neural tube defects. Similar birth defects were reported in other populations exposed to war contaminants. While the causes of increased prevalence of birth defects are under investigation, we opted to release this communication to contribute to exploration of these issues. By using a questionnaire, containing residential history and activities that may have led to exposure to war contaminants, retrospective reproductive history of four polygamous Fallujah families were documented. Our findings point to sporadic, untargeted events, with different phenotypes in each family and increased recurrence. The prevalence of familial birth defects after 2003 highlights the relevance of epigenetic mechanisms and offers insights to focus research, with the aim of reducing further damage to people's health.

T Lymphocyte Activation Profiles in Peripheral Blood of Long-Versus Short-Term Residents of Kuwait: Comparison with Asthmatics

Introduction: During the Arabian Gulf Wars of 1991 and 2003, the resident population of Kuwait sustained heavy exposure to environmental toxicants introduced by military activities. No comprehensive studies have been conducted to assess how exposure to the wartime and postwar environment may have altered the fundamental patterns of immune reactivity among Kuwaitis in ways that affect pathogenesis of disease. This present study addresses this issue by characterising immunological features of asthma and allergies in a Kuwaiti population that is unique and possibly correlates with toxicant exposures. Materials and Methods: Twenty-five long-term residents of Kuwait afflicted with bronchial asthma concurrent with rhinitis; and 2 healthy control groups: 18 long-term residents and 10 newcomers to Kuwait were evaluated by 2- and 3-colour flow cytometry for peripheral blood T cell subpopulation frequencies. Results: Relative to healthy, long-term residents, significantly elevated frequencies of all activated cell phenotypes were observed in the blood of the asthmatic group (P <0.05 to P <0.001), except for CD8+HLA-DR+ cells and a presumed T-regulatory (Treg) subpopulation: CD4+CD25high. The asthmatic group was also observed to have larger populations of CD3+ (pan-T cells), CD4+ (T helper cells) and CD8+ (cytotoxic T cells), CD3+CD56 (NKT-like cells) and CD56+CD16+ (NK cells) compared to healthy long-term residents. Compared to healthy recent immigrants, the blood of long-term residents contained elevated levels of CD3+CD56+ (NK-like), CD4+CD45RA+/CD45RO+ (Naive-to-Memory Transitional), but lower CD4+CD25+high (Treg) (P <0.05). Conclusions: Elevated representation of natural killer (NKT)-like and memory phenotypes may predispose long-term residents towards enhanced susceptibility for airway disease; while at the same time, reducing representation of Treg cells which are protective against airway disease, and this may increase vulnerability to these syndromes among the residents of Kuwait. These results may provide insight into the features of immunopathogenesis of asthma and allergies in Kuwait that arise as a result of the special environment of the country. Key words: Asthma, Immune reactivity, Kuwait, Rhinitis, T cells

Renal effects of exposure to natural and depleted uranium: a review of the epidemiologic and experimental data

Elevated levels of naturally occurring uranium in groundwater have been found in small geographic areas throughout the world. Relevant research was reviewed pertaining to natural and depleted uranium (DU) exposure and nephrotoxicity, including epidemiologic community-based and occupational studies, studies of Gulf War veterans exposed to DU, and experimental studies in animals. Occupational cohort studies do not provide evidence of an increased risk of kidney-related mortality among uranium-exposed workers. However, occupational and community-based studies of populations chronically exposed to elevated drinking-water concentrations of uranium provide some evidence of adverse renal effects, as assessed by biomarkers of proximal tubule damage such as urinary levels of glucose, calcium, and various low-molecular-weight proteins. Indications of proximal tubule effects, as evidenced by increased urinary β(2)-microglobulin and retinol binding protein levels, were also seen in the most recent follow-up surveillance study of Gulf War veterans exposed to DU. The reported β(2)-microglobulin levels in these studies were generally considered to be within normal limits, but the long-term implications of the observed variation in these levels are not established. The kidney was observed to be a target of uranium toxicity following oral and implantation exposure routes in several animal species. The interpretation and importance of the observed changes in biomarkers of proximal tubule function are important questions that indicate the need for additional clinical, epidemiological, and experimental research.

The toxicity of depleted uranium

Depleted uranium (DU) is an emerging environmental pollutant that is introduced into the environment primarily by military activity. While depleted uranium is less radioactive than natural uranium, it still retains all the chemical toxicity associated with the original element. In large doses the kidney is the target organ for the acute chemical toxicity of this metal, producing potentially lethal tubular necrosis. In contrast, chronic low dose exposure to depleted uranium may not produce a clear and defined set of symptoms. Chronic low-dose, or subacute, exposure to depleted uranium alters the appearance of milestones in developing organisms. Adult animals that were exposed to depleted uranium during development display persistent alterations in behavior, even after cessation of depleted uranium exposure. Adult animals exposed to depleted uranium demonstrate altered behaviors and a variety of alterations to brain chemistry. Despite its reduced level of radioactivity evidence continues to accumulate that depleted uranium, if ingested, may pose a radiologic hazard. The current state of knowledge concerning DU is discussed.

The British river of the future: how climate change and human activity might affect two contrasting river ecosystems in England

The possible effects of changing climate on a southern and a north-eastern English river (the Thames and the Yorkshire Ouse, respectively) were examined in relation to water and ecological quality throughout the food web. The CLASSIC hydrological model, driven by output from the Hadley Centre climate model (HadCM3), based on IPCC low and high CO(2) emission scenarios for 2080 were used as the basis for the analysis. Compared to current conditions, the CLASSIC model predicted lower flows for both rivers, in all seasons except winter. Such an outcome would lead to longer residence times (by up to a month in the Thames), with nutrient, organic and biological contaminant concentrations elevated by 70-100% pro-rata, assuming sewage treatment effectiveness remains unchanged. Greater opportunities for phytoplankton growth will arise, and this may be significant in the Thames. Warmer winters and milder springs will favour riverine birds and increase the recruitment of many coarse fish species. However, warm, slow-flowing, shallower water would increase the incidence of fish diseases. These changing conditions would make southern UK rivers in general a less favourable habitat for some species of fish, such as the Atlantic salmon (Salmo salar). Accidental or deliberate, introductions of alien macrophytes and fish may change the range of species in the rivers. In some areas, it is possible that a concurrence of different pressures may give rise to the temporary loss of ecosystem services, such as providing acceptable quality water for humans and industry. An increasing demand for water in southern England due to an expanding population, a possibly reduced flow due to climate change, together with the Water Framework Directive obligation to maintain water quality, will put extreme pressure on river ecosystems, such as the Thames.

Depleted uranium: properties, military use and health risks

This article describes uranium and depleted uranium (DU), their similar isotopic compositions, how DU arises, its use in munitions and armour-proofing, and its pathways for human exposures. Particular attention is paid to the evidence of DU's health effects from cell and animal experiments and from epidemiology studies. It is concluded that a precautionary approach should be adopted to DU and that there should be a moratorium on its use by military forces. International efforts to this end are described.

Accumulation and distribution of uranium in rats after implantation with depleted uranium fragments

PURPOSE

The aim of our study was to clarify the accumulation and distribution of uranium in depleted uranium (DU) implanted rats.

MATERIALS AND METHODS

Male Sprague-Dawley rats were surgically implanted in gastrocnemius muscle with DU fragments at 3 dose levels (low, medium and high), and biologically inert tantalum (Ta) fragments were used as controls. At 1 day and 7, 30, 90, 180 and 360 days after implantation, the rats were euthanized and tissue samples including serum and urine were collected to analyze the uranium levels by inductively coupled plasma-mass spectrometry (ICP-MS).

RESULTS

At all time points, uranium levels in all the DU implanted groups were higher than that in Ta control group, and uranium concentrations in kidney and bone were significantly greater than that in other tissues. Otherwise, uranium concentrations increased with a close correlation to the implanted DU doses and duration of exposure, with a peak at 90 days post-implantation, after which followed by a decreasing period, but still maintained at a relatively high level even at 360 days post- implantation. The uranium concentrations in bone were 6.92 +/- 0.97 microg U/g, 16.35 +/- 1.67 microg U/g and 21.64 +/- 3.68 microg U/g in the low-, medium- and high-dose group animals, while values in kidney tissues were 10.66 +/- 1.10 microg U/g, 14.06 +/- 1.28 microg U/g and 17.79 +/- 2.87 microg U/g, respectively, at 360 days post-implantation.

CONCLUSION

It was concluded that kidney and bone are the primary reservoirs for uranium redistributed from intramuscularly embedded fragments, and the accumulations in kidney, bone and many other tissues suggest the potential for unanticipated physiological consequences of chronic exposure to DU.

Two-generation reproductive toxicity study of implanted depleted uranium (DU) in CD rats

Depleted uranium (DU) munitions and armor plating have been used in several conflicts over the last 17 yr, including the Persian Gulf War and the Iraq War. Because of its effectiveness and availability, DU will continue to be used in military applications into the foreseeable future. There is much controversy over the use of DU in weapons and equipment because of its potential radiological and toxic hazards, and there is concern over the chronic adverse health effects of embedded DU shrapnel in war veterans and bystanders. This study evaluated the effects of long-term implantation of DU on the reproductive success of F0 generation adults and development and survival of subsequent F1 and F2 generations in a two-generation reproductive toxicity study. F0 generation Sprague-Dawley rats, 8 wk of age, were surgically implanted with 0, 4, 8, 12, or 20 DU pellets (1 x 2 mm). Inert implant control animals were implanted with 12 or 20 tantallum (Ta) pellets. The F0 generation was then mated at 120 d post DU implantation. In the F0 generation, when measured on postimplantation d 27 and 117, uranium was present in the urine of DU-implanted animals in a dose-dependent manner. F0 reproductive success was similar across treatment groups and the maternal retrieval test revealed no changes in maternal behavior. DU implantation exerted no effect on the survival, health, or well-being of the F0 generation. Necropsy results of F0 animals were negative with the exception of a marked inflammatory response surrounding the implanted DU pellets. For the F1 generation, measures of F1 development through postnatal day (PND) 20 were unremarkable and no gross abnormalities were observed in F1 offspring. No uranium was detected in whole-body homogenates of PND 4 or PND 20 pups. Necropsy findings of F1 PND 20 pups were negative and no instances of ribcage malformation were observed in F1 PND 20 pups. Body weight and body weight gain of F1 rats through PND 120 were similar across treatment groups. Eight of 414 F1 animals observed from PND 20 to 120 died of unknown causes; 7 were from litters of DU-implanted F0 mating pairs. F1 mating success at 10 wk of age was an overall 70% compared with 91% for F0 mating pairs. Mating success was similar between F1 animals derived from DU-implanted F0 adults and those derived from F0 implant control adults suggesting that the comparatively low mating success was not due to F1 DU exposure. The gestational index of F1 animals derived from mid-dose F0 mating pairs was found to be lower compared with F1 controls. The average gestation duration of F1 animals derived from high-dose F0 mating pairs was found to be significantly longer than F1 controls. F1 sperm motility analyses did not differ among experimental groups and no gross abnormalities were identified at necropsy among surviving F1 animals at PND 120. Histopathology of kidneys, spleen, thymus, bone marrow, ovaries, and testes of F1 high-dose animals did not differ from F1 controls. F1 high-dose females had significantly higher mean relative liver and heart weights compared with F1 controls; the biological relevance of this finding could not be determined. For the F2 generation, measures of F2 development through PND 20 were unremarkable and no gross abnormalities were observed in F2 offspring. Necropsy findings of F2 PND 20 pups were negative and no instances of ribcage malformation were observed in F2 PND 20 pups. Body weight and body weight gain of F2 rats through PND 90 were similar across treatment groups. Mean relative heart weights of males derived from high-dose F0 parents were significantly lower compared with F2 controls. Sperm motility and concentration analysis of F2 males at PND 90 were similar across F2 groups. Overall, the consistent absence of positive findings in this study seems to suggest that DU is not a significant reproductive or developmental hazard, particularly when one considers that mid- and high-dose rats were implanted with the equivalent of 0.3 and 0.5 lb of DU in a 70-kg human, respectively. However, the findings that seven of eight F1 adults that died postweaning were from DU-implanted F0 mating pairs, and that mean relative heart weights were elevated in high-dose F1 and F2 pups, suggest conservatism is warranted in characterizing the reproductive and teratogenic hazards of embedded DU until further studies are completed.

Efficacy of oral and intraperitoneal administration of CBMIDA for removing uranium in rats after parenteral injections of depleted uranium

The efficacy of oral administration of the chelating agent catechol-3,6-bis(methyleiminodiacetic acid) (CBMIDA) for removing uranium from rats after intraperitoneal (i.p.) and intramuscular (i.m.) injections of depleted uranium (DU) was examined and the results with those by the i.p. injection of CBMIDA were compared. In Experiment 1, after a single i.p. injection of 8 mg kg(-1) of DU of rat's body weight, 35 8-week-old male rats were divided into seven groups consisting of five rats each. Three groups were administered with CBMIDA 240, 720 or 1200 mg kg(-1) of rat's body weight orally once a day, and three other groups received an i.p. injection of 240, 480 or 720 mg kg(-1) CBMIDA for 3 d, starting 30 min after DU injection on the first day. One DU group received no CBMIDA. The remaining five intact rats were used as a control group. Rats were killed 6 d after DU injection. In Experiment 2, the 35 male rats that received a single i.m. injection of 8 mg kg(-1) DU were divided into seven groups, and the rats of each group received the same doses of CBMIDA on the same schedules of treatment as those described in Experiment 1. The results obtained in Experiment 1 indicated that orally administered CBMIDA significantly increased the excretion of uranium at doses of 720 and 1200 mg kg(-1) and decreased uranium concentrations, particularly in the kidney, at all the doses tested, and the effects were almost equal to those of the i.p. injection. The lack of increases in creatinine and blood urea nitrogen in serum indicated that CBMIDA is efficacious in preventing the renal dysfunction caused by uranium. In Experiment 2, oral administration of CBMIDA significantly increased uranium excretion and significantly decreased uranium concentrations, particularly in the kidneys, at all the doses tested, and the effects were almost equal to those of the i.p. injection. However, these effects of CBMIDA on the i.m.-injected DU were lower than those of the i.p.-injected DU in Experiment 1. These results indicated that oral administration of CBMIDA has almost the same efficacy as that administered by the parenteral route. Additional study is necessary to obtain satisfactory effects for the clinical use of CBMIDA, particularly for wounds contaminated accidentally with uranium.

Depleted uranium contamination by inhalation exposure and its detection after approximately 20 years: implications for human health assessment

Inhaled depleted uranium (DU) aerosols are recognised as a distinct human health hazard and DU has been suggested to be responsible in part for illness in both military and civilian populations that may have been exposed. This study aimed to develop and use a testing procedure capable of detecting an individual's historic milligram-quantity aerosol exposure to DU up to 20 years after the event. This method was applied to individuals associated with or living proximal to a DU munitions plant in Colonie New York that were likely to have had a significant DU aerosol inhalation exposure, in order to improve DU-exposure screening reliability and gain insight into the residence time of DU in humans. We show using sensitive mass spectrometric techniques that when exposure to aerosol has been unambiguous and in sufficient quantity, urinary excretion of DU can be detected more than 20 years after primary DU inhalation contamination ceased, even when DU constitutes only approximately 1% of the total excreted uranium. It seems reasonable to conclude that a chronically DU-exposed population exists within the contamination 'footprint' of the munitions plant in Colonie, New York. The method allows even a modest DU exposure to be identified where other less sensitive methods would have failed entirely. This should allow better assessment of historical exposure incidence than currently exists.

Evaluation of the effect of implanted depleted uranium (DU) on adult rat behavior and toxicological endpoints

In 2002, the Naval Health Research Center Toxicology Detachment began a study to determine the effects of surgically implanted depleted uranium (DU) pellets on adult rat (e.g., P1 generation) health and reproduction. In this report, the effect of implanted DU on adult rat behavior and health is described. Adult Sprague-Dawley (SD) rats, 8 wk of age, were surgically implanted with 0, 4, 8, 12, or 20 DU pellets (1 x 2 mm); 20 DU pellets of size 1 x 2 mm approximates to 0.22 kg (0.5 lb) of DU in a 70-kg (154 lb) person. Control animals were implanted with 12 or 20 tantallum (Ta) pellets. The animals were then housed for up to 150 d postimplantation or 20% of an assumed 2-yr life span for rats. The concentration of uranium in urine directly correlated with the number of implanted DU pellets, indicating that DU was migrating into the body from the implanted pellets. Three male and 4 female animals died during the 150-d period of causes apparently not related to DU implantation. Behavioral testing found no definitive evidence of neurobehavioral perturbations associated with DU implantation. Uranium translocated to tissues known to sequester uranium (bone, teeth, and kidneys), but uranium concentrations varied considerably within each dose group and did not follow a dose-response pattern as anticipated. Serum chemistry values were within normal ranges for the SD rat. However, alanine aminotransferase measurements were significantly lower for rats implanted with 20 DU pellets as compared to sham surgery controls but not when compared to animals implanted with Ta pellets only. Phosphate measurements were significantly lower for female rats implanted with 20 DU pellets as compared to both sham surgery controls and animals implanted with Ta pellets only. Monocyte ratios were higher in adult rats implanted with 20 DU pellets as compared to sham surgery controls but not when compared to animals implanted with 20 Ta pellets. Mean platelet volume was found to be significantly lower for rats implanted with 20 DU pellets as compared to sham surgery controls but not when compared to animals implanted with 20 Ta pellets. Gross necropsy found no obvious tissue abnormalities in implanted rats, and the weights of major tissues did not differ between Ta- and DU-implanted animals. Histopathologic analysis of major tissues from animals implanted with 0 pellets, 20 Ta pellets, or 20 DU pellets found no differences between treatment groups. The findings of this study indicate that implantation of up to 20 DU pellets in adult rats did not have a significant negative impact on their general health and neurobehavioral capacities when assessed after 150 d of pellet implantation. However, the growing body of data on the potential health effects associated with DU exposure warrants further studies involving higher embedded DU body burdens in conjunction with longer surveillance periods postimplantation.