Human biomonitoring of antimony

Biomonitoring of firefighting forces: a review on biomarkers of exposure to health-relevant pollutants released from fires

Occupational exposure as a firefighter has recently been classified as a carcinogen to humans by International Agency for Research on Cancer (IARC). Biomonitoring has been increasingly used to characterize exposure of firefighting forces to contaminants. However, available data are dispersed and information on the most relevant and promising biomarkers in this context of firefighting is missing. This review presents a comprehensive summary and critical appraisal of existing biomarkers of exposure including volatile organic compounds such as polycyclic aromatic hydrocarbons, several other persistent other organic pollutants as well as heavy metals and metalloids detected in biological fluids of firefighters attending different fire scenarios. Urine was the most characterized matrix, followed by blood. Firefighters exhaled breath and saliva were poorly evaluated. Overall, biological levels of compounds were predominantly increased in firefighters after participation in firefighting activities. Biomonitoring studies combining different biomarkers of exposure and of effect are currently limited but exploratory findings are of high interest. However, biomonitoring still has some unresolved major limitations since reference or recommended values are not yet established for most biomarkers. In addition, half-lives values for most of the biomarkers have thus far not been defined, which significantly hampers the design of studies. These limitations need to be tackled urgently to improve risk assessment and support implementation of better more effective preventive strategies.

Association between maternal antimony exposure and risk of gestational diabetes mellitus: A birth cohort study

BACKGROUND

A small number of epidemiological studies have suggested the association of antimony (Sb) exposure with type 2 diabetes risk. However, little is known about the relationship between Sb exposure during pregnancy and risk of gestational diabetes mellitus (GDM).

OBJECTIVES

To investigate the associations of urinary Sb concentrations with GDM risk and blood glucose levels in pregnant women.

METHODS

We analyzed the baseline data of 1789 pregnant women enrolled in the Birth Cohort Study on Prenatal Environments and Offspring Health (PEOH) in Guangzhou, China. Sb concentrations in urine were measured by inductively coupled plasma mass spectrometry (ICP-MS). Logistic regression and analysis of covariance were used to evaluate associations of Sb exposure with GDM risk and blood glucose levels.

RESULTS

A total of 437 (24.4%) women were diagnosed with GDM. The relative risk of GDM for women in the highest quartile of creatinine-corrected Sb (CC-Sb) concentrations was 1.55 [RR (95% CI) = 1.55 (1.12, 2.15), p-trend = 0.005], compared with women in the lowest quartile. Moreover, the women in the top quartile of CC-Sb levels had a 5.2% higher 1 h blood glucose and a 4.2% higher 2 h blood glucose than those in the bottom quartile. We also found an interactive effect between maternal age and CC-Sb on the risk of GDM (p-interaction < 0.001).

CONCLUSION

This study suggested significant positive associations of Sb exposure with increased GDM risk and impaired blood glucose homeostasis in pregnant women, and the Sb-GDM association might be modified by maternal age.

Exposure profile of mercury, lead, cadmium, arsenic, antimony, copper, selenium and zinc in maternal blood, cord blood and placenta: the Tohoku Study of Child Development in Japan

BACKGROUND

The effects of prenatal exposure to toxic elements on birth outcomes and child development have been an area of concern. This study aimed to assess the profile of prenatal exposure to toxic elements, arsenic (As), bismuth (Bi), cadmium (Cd), mercury (total mercury (THg), methylmercury (MHg), inorganic mercury (IHg)), lead (Pb), antimony (Sb) and tin (Sn), and essential trace elements, copper (Cu), selenium (Se) and zinc (Zn), using the maternal blood, cord blood and placenta in the Tohoku Study of Child Development of Japan (N = 594-650).

METHODS

Inductively coupled plasma mass spectrometry was used to determine the concentrations of these elements (except mercury). Levels of THg and MeHg were measured using cold vapour atomic absorption spectrophotometry and a gas chromatograph-electron capture detector, respectively.

RESULTS

Median concentrations (25th-75th) of As, Cd, Pb, Sb, Sn and THg in the maternal blood were 4.06 (2.68-6.81), 1.18 (0.74-1.79), 10.8 (8.65-13.5), 0.2 (0.06-0.40) and 0.2 (0.1-0.38) ng mL^-1 and 5.42 (3.89-7.59) ng g^-1, respectively. Median concentrations (25th-75th) of As, Cd, Pb, Sb, Sn and THg in the cord blood were 3.68 (2.58-5.25), 0.53 (0.10-1.25), 9.89 (8.02-12.5), 0.39 (0.06-0.92) and 0.2 (0.2-0.38) ng mL^-1 and 9.96 (7.05-13.8) ng g^-1, respectively.

CONCLUSIONS

THg and Sb levels in the cord blood were twofold higher than those in the maternal blood. Cord blood to maternal blood ratios for As, Cd and Sb widely varied between individuals. To understand the effects of prenatal exposure, further research regarding the variations of placental transfer of elements is necessary.

Maternal exposure to alkali, alkali earth, transition and other metals: Concentrations and predictors of exposure

Most studies of metals exposure focus on the heavy metals. There are many other metals (the transition, alkali and alkaline earth metals in particular) in common use in electronics, defense industries, emitted via combustion and which are naturally present in the environment, that have received limited attention in terms of human exposure. We analysed samples of whole blood (172), urine (173) and drinking water (172) for antimony, beryllium, bismuth, cesium, gallium, rubidium, silver, strontium, thallium, thorium and vanadium using ICPMS. In general most metals concentrations were low and below the analytical limit of detection with some high concentrations observed. Few factors examined in regression models were shown to influence biological metals concentrations and explained little of the variation. Further study is required to establish the source of metals exposures at the high end of the ranges of concentrations measured and the potential for any adverse health impacts in children.

Phytoavailability of antimony and heavy metals in arid regions: the case of the Wadley Sb district (San Luis, Potosí, Mexico)

This paper presents original results on the Sb and heavy metals contents in sediments and waste tailings, plants and water from the giant Wadley antimony mine district (San Luis Potosí State, Mexico). The dominant antimony phases in mining wastes are stibiconite, montroydite and minor hermimorphite. The waste tailings contain high concentrations of metals and metalloids (antimony, iron, zinc, arsenic, copper, and mercury). Manganese, copper, zinc, and antimony contents exceed the quality guidelines values for groundwater, plants and for waste tailings. Results indicate that peak accumulation is seasonal due to the concentration by high metabolism plants as Solanaceae Nicotiana. The metal phytoavailability in waste tailings is highly dependant on the metal speciation, its capability to be transported in water and, more particularly, the plant metabolism efficiency.

Health risk associated with dietary co-exposure to high levels of antimony and arsenic in the world's largest antimony mine area

Like arsenic (As), antimony (Sb) is known to be a genotoxic element in vitro and in vivo. Sb is now recognized as a global contaminant and has aroused the global concerns recently. However, knowledge is scarce concerning the transfer of Sb from the environment to humans and the related hazards to human health. In this pilot study, the health risk and main pathway of long-term human exposure to Sb and As for residents around Chinese Xikuangshan (XKS) Sb mine, the world's largest Sb mine, were evaluated by dietary exposure and hair accumulations survey. The concentrations and species of Sb and As in food samples (n=209) from three main categories and six subcategories, and in hair samples (n=89) were determined. Residents in the vicinity of XKS had an estimated dietary intake of Sb (554 μg/day) which was 1.5 times higher than the tolerable daily intake (TDI) (Sb, 360 μg/day), whereas their dietary intake of inorganic As (107 μg/day) was slightly lower than the provisional tolerable weekly intake (PTWI) of 15 μg/kg BW/week (equal to 129 μg As/day). Hair Sb and As concentrations (Sb, 15.7 mg/kg, DW; As, 3.99 mg/kg, DW) in XKS residents are both above the normal/toxic level. Rice, vegetables (especially leafy vegetable), drinking water, and meat/poultry were the dominant dietary intake sources of Sb for the residents. In contrast, rice was the uniquely dominant dietary intake source of As. Antimonate (Sb(V)) was the dominant Sb species in vegetables, drinking water and residents' hairs. This study highlighted the difference of exposure characteristics between Sb and As. The preliminary results suggested that dietary exposures to Sb, rather than As, was the dominant health risk to local residents. Nevertheless, the adverse effects of As levels on the health of residents still can not be ignored since the elevated As concentrations in human hair have reached the critical level for health risks. In addition, this pilot study did not consider the possible Sb and As combined effects.

The exposure to and health effects of antimony

CONTEXT

This minireview describes the health effects of antimony exposure in the workplace and the environment.

AIM

To collate information on the consequences of occupational and environmental exposure to antimony on physiological function and well-being.

METHODS

The criteria used in the current minireview for selecting articles were adopted from proposed criteria in The International Classification of Functioning, Disability and Health. Articles were classified from an acute and chronic exposure and toxicity thrust.

RESULTS

The proportion of utilised and non-utilised articles was tabulated. Antimony toxicity is dependent on the exposure dose, duration, route (breathing, eating, drinking, or skin contact), other chemical exposures, age, sex, nutritional status, family traits, life style, and state of health. Chronic exposure to antimony in the air at levels of 9 mg/m(3) may exacerbate irritation of the eyes, skin, and lungs. Long-term inhalation of antimony can potentiate pneumoconiosis, altered electrocardiograms, stomach pain, diarrhea, vomiting, and stomach ulcers, results which were confirmed in laboratory animals. Although there were investigations of the effect of antimony in sudden infant death syndrome, current findings suggest no link. Antimony trioxide exposure is predominant in smelters. Mining and exposure via glass working, soldering, and brazing are also important.

CONCLUSION

Antimony has some useful but undoubtedly harmful effects on health and well-being and measures need to be taken to prevent hazardous exposure of the like. Its biological monitoring in the workplace is essential.

Concentration of metals in blood of Maine children 1-6 years old

Blood lead concentrations are higher in young children than in other age groups, whereas little is known regarding concentrations of other metals in young children. We measured the concentrations of a suite of metals in the blood of children 1-6 years of age, and assessed potential differences by age, season, or region of Maine. We used blood submitted to the Maine State Health and Environmental Testing Laboratory for blood lead analysis to determine the concentrations of arsenic (As), antimony (Sb), cadmium (Cd), manganese (Mn), mercury (Hg), selenium (Se), tin (Sn), and uranium (U) in 1350 children 1-6 years of age. The essential metals Mn and Se were detected in all samples, and As and Sb were detected in >90% of samples. Hg was detected in approximately 60% of samples. U and Cd were less often detected in blood samples, at approximately 30% and 10% of samples, respectively. Sn was not detected in any sample. Concentrations of As, Hg, and Se increased with age, whereas Sb decreased with age. Concentrations also varied by season and region for some though not all metals. Significant pairwise correlations were observed for a number of metals. Blood is a reasonable compartment for measurement of most of these metals in young children. The use of convenience samples provided a cost-effective mechanism for assessing exposure of young children in Maine.

Bioaccessibility, solid phase distribution, and speciation of Sb in soils and in digestive fluids

Antimony (Sb) is a pollutant found in lead-contaminated soils and occurs mainly in oxidation states Sb(III) or Sb(V), this latter being the less toxic forms to organisms. In human health risk assessment, soil ingestion is one of a major exposure route in which Human bioavailability is not considered. The objectives of this paper were to establish a link between Sb speciation in soils and its bioaccessibility considering the possible evolution of the speciation in the digestive tract. Four soils were sampled around a former lead-extraction site. Total Sb content on these soils ranged between 26mgkg(-1) and 1150mgkg(-1). Sb bioaccessibility in the soils was measured using an in vitro Bioaccessibility Group Research Europe (BARGE) digestion test. A sequential extraction procedure and physical analyses were carried out on these samples to estimate Sb speciation in soils. Differential pulse anodic stripping voltammetry (DPASV) was also used to study the evolution of Sb speciation during the digestion process. For the four samples, Sb bioaccessibility was low, ranging between 1.5% and 12% of total Sb content. Sequential extractions and physical analysis on the most contaminated soil showed that Sb was mostly occurring in the iron oxide and sulphide phases and in the pentavalent form. No change of this speciation was occurring during the digestion process. Determination of the Sb speciation in the soil matrix is thus an accurate way to demonstrate that this metalloïd can be considered as a non major issue in the overall risk characterisation if it occurs under the pentavalent form.

Trimethylantimony dichloride causes genotoxic effects in Chinese hamster ovary cells after forced uptake

In our study, we demonstrate that trimethylantimony dichloride (TMSb) does not induce micronucleus (MN) formation, chromosome aberrations (CA) or sister chromatid exchanges (SCE) under normal conditions in Chinese hamster ovary (CHO-9) cells in vitro up to an applied concentration of 1 mM, nor is it significantly cytotoxic. TMSb is taken up by the cells in a dose-dependent manner, but the percentage uptake of incubation substrate is low (max 0.05%). Intracellular TMSb concentration is two-fold increased after electroporation and under these forced uptake conditions MN formation is also significantly elevated. These data indicate that resistance to TMSb in CHO-9 cells occurs at the uptake and not at the intracellular level.

Determination of antimony in human blood with inductively coupled plasma-mass spectrometry

A method is presented for the determination of antimony in whole human blood samples with an ICP-MS instrument using a quadrupole mass analyzer. A nitric acid/hydrogen peroxide open digestion procedure was employed for the blood sample treatment and preparation for analysis. The precision and accuracy of the method were evaluated by analyzing several Seronorm trace elements whole blood reference materials. The precision of the method at various antimony levels was better than 4% RSD and the recovery was greater than 92% at all levels. The detection limit, calculated as three times the standard deviation of the blank (3sigma, n= 12), was 0.03 microg L(-1). The method was successfully applied for the determination of antimony in blood samples from school children in rural areas of Kwazulu/Natal, South Africa and adults from Dearborn, Michigan. Blood antimony levels ranged from <0.03 to 3.82 microg L(-1) in children and 1.40 to 4.35 microg L(-1) for adults.

Antimony excretion in a patient with renal impairment during meglumine antimoniate therapy

Meglumine antimoniate was administered to a patient with visceral leishmaniasis with normal renal function. Soon after the first intramuscular administration of meglumine antimoniate 20 mg/kg, equivalent to 510 mg antimony (Sb), the patient developed septic shock with oliguria. Creatinine clearance decreased to 23 ml/minute. Treatment was discontinued, and Sb urinary excretion was measured. After the initial dose, 500.25 mg Sb was recovered in urine over 8 days, corresponding to 98% of the amount of Sb given intramuscularly (66% eliminated within first 48 hrs). Nine days after the dose, meglumine antimoniate was reintroduced at a dosage of 11.7 mg/kg (equivalent to 300 mg Sb) every 48 hours with good tolerance. At that time creatinine clearance had returned to 87.8 ml/minute. By day 14 of therapy the interval was reduced to daily administration of the same dose; the dosage was increased to 16.6 mg/kg/day (equivalent to 425 mg Sb) from day 17 to day 31. The patient eventually completely recovered and was discharged with normal renal function. Although no specific guidelines exist for dosage adjustment in renal failure, monitoring of Sb urinary excretion indicates that the kidneys are the almost exclusive route of elimination.

Comparison of representative ranges based on U.S. patient population and literature reference intervals for urinary trace elements

Reference intervals for trace elements are very hard to obtain because of the difficulty of defining a nonexposed reference population. However, representative ranges for trace elements obtained from a general patient population can provide useful information in interpreting laboratory results. We have used urine specimens submitted for trace metal analysis from patients residing in the United States to calculate representative ranges for 25 urinary trace elements, and to compare them to reference values taken from the literature. All urine analytes were measured by inductively-coupled plasma-mass spectrometry except chromium, which was measured by graphite furnace atomic absorption spectroscopy. For representative range calculation two approaches were used. In the non-parametric calculation first, the top 10% of results were discarded assuming that those specimens came from individuals with unusually high trace element exposures. Next the central 95% of the remaining data was taken as the reference interval. In the parametric calculation the specimens from exposed or not healthy individuals were assumed to appear as outliers and were discarded. The mean and S.D. were calculated, and used to determine representative ranges. The two approaches yielded very similar results, and worked remarkably well for 14 analytes. There were minor discrepancies for 7 analytes, and major for 4 analytes. All analyses of urinary trace elements included a urine creatinine value, which was used to express urinary trace element concentrations in terms of creatinine ratio. This corrects for differences in urine concentration that affects the results for random specimens.