Relationship between serum selenium, sociodemographic variables, other trace elements and lipid profile in an adult Spanish population.

INTRODUCTION: Several studies have shown an inverse relationship between selenium status and cardiovascular health, although epidemiologic evidence yielded by the randomized trials did not find a beneficial effect of selenium administration. The aim of this study was to analyze the association between serum selenium levels and lipid profile adjusted by age, sex and other associated factors among a general adult population in Spain. MATERIALS AND METHODS: We recruited 372 hospital employee volunteers (60 men and 312 women) with a mean age of 47 (SD: 10.9), whom were given a standardized questionnaire. Serum selenium concentration was measured by electrothermal atomization atomic absorption spectrometry. Serum copper and zinc concentrations were measured using flame atomic absorption spectrometry. RESULTS: The mean of serum selenium was 79.5µg/L (SD: 11.7) with no sex-dependent differences. In the multivariate linear regression analysis, the associated factors with the mean levels of selenium were: age (ß=0.223; CI 95%: 0.101-0.345), p<0.001; widowhood (ß=-9.668; CI 95%: -17.234 to -2.102), p=0.012; calcium supplements (ß=3.949; CI 95%: 0.059-7.838), p=0.047; zinc (ß=0.126; CI 95%: 0.013-0.238), p=0.028 and glucose (ß=0.172; CI 95%: 0.062- 0.281), p=0.002; Participants with serum selenium≥79.5µg/L were 1.98 (OR=1.98; CI 95% 1.17-3.35; p=0.011) and 2.04 times (OR=2.04; CI 95% 1.06-3.97; p=0.034) more likely to have cholesterol ≥200mg/dL and LDL-c ≥100mg/dL respectively than those with serum selenium <79.5µg/L. CONCLUSIONS: Higher selenium was positively associated with increased total and LDL cholesterol but not with HDL-c and triglycerides. More studies are needed in order to confirm the lower serum selenium findings in widows.

Trace elements in bipolar disorder.

INTRODUCTION: Trace elements may play an important role in bipolar disorders. The objective of this study is to determine serum copper and zinc, blood lead and cadmium and urine lead, cadmium and thallium concentrations in patients diagnosed with bipolar disorders and to compare these levels with those of a healthy control group. MATERIALS AND METHODS: A total of 25 patients diagnosed with bipolar disorder and 29 healthy subjects participated in this study. Serum copper and zinc concentrations were measured using flame atomic absorption spectrometry; the blood lead and cadmium concentrations were measured by electrothermal atomization atomic absorption spectrometry with Zeeman background correction; urine lead, cadmium and thallium concentrations were measured by inductively coupled plasma mass spectrometry. RESULTS: Median blood and urine lead and cadmium levels were significantly higher among the bipolar patients than among the control group: Blood lead (µg/dL): patient median: 3.00 (IQR: 1.40-4.20); control median (µg/dL): 2.20 (IQR: 0.90-3.00) p=0.040. Blood cadmium (µg/L): patient median: 0.39 (IQR: 0.10-1.15); control median: 0.10 (IQR: 0.10-0.17) p<0.001. The median of cadmium (µg/L) in patients who smoked (1.20 IQR: 0.44-2.30) was higher than that in non-smokers (0.12 IQR: 0.10-0.34) p<0.001. There was a statistically significant increase (p=0.001) in zinc levels among patients in the manic phase (mean 111.28, SD: 33.36 µg/dL) with respect to the control group (mean 86.07, SD: 12.39 µg/dL). CONCLUSIONS: The results suggest that there could be higher levels of some toxic trace elements in the group of patients with bipolar disorder than in the healthy control group.

Blood lead and cadmium levels in a six hospital employee population. PESA study, 2009.

INTRODUCTION: Exposure to lead and cadmium is a public health problem due to the broad exposure to these toxic substances among the general population. The objective of this study is to determine blood lead and cadmium concentrations in a working population drawn from six university hospitals in Madrid, Getafe, Cartagena, Santiago de Compostela, Santander and Palma de Mallorca (Spain) and to identify associated factors. MATERIALS AND METHODS: 951 individuals participated in the study and were administered the standardized PESA® questionnaire regarding exposure to lead and cadmium. The blood lead and cadmium concentrations were measured by electrothermal atomization atomic absorption spectrometry with Zeeman background correction in Perkin-Elmer spectrometers, guaranteeing the transferability of the results. RESULTS: The median overall blood lead concentration was: 1.6 µg/dL (IQR: 0.9-2.7) and that of cadmium was: 0.21 µg/L (IQR: 0.10-0.50). There were significant differences in lead levels between men (2 µg/dL) and women (1.5 µg/dL), postmenopausal (2.6 µg/dL) and premenopausal women (1.1 µg/dL), and between participants who cooked in earthenware (2.1 µg/dL) and those who did not (1.5 µg/dL). The median of cadmium in women (0.24 µg/L) was higher than in men (0.11 µg/L) and was also higher in subjects who smoked (0.70 µg/L) than in non-smokers (0.13 µg/L). CONCLUSIONS: A reduction in blood lead and cadmium levels was observed with respect to previous studies carried out in Spain. Nevertheless, the results suggest there are certain factors which increase risk such as age, gender, menopause, age of housing, cooking in lead-glazed earthenware and exposure to cigarette smoke.

Measurement of cerium in human breast milk and blood samples.

The aim of this study was to evaluate the relationship between cerium content in human breast milk and blood plasma or serum. Blood samples and breast milk at various stages of lactation, from 5 days to 51 weeks post partum, were donated by 42 healthy breast-feeding mothers from Munich, Germany and by 26 lactating Spanish mothers from Madrid at 4 weeks post partum. Inductively coupled plasma mass spectrometry was applied for the determination of cerium in the biological samples. Cerium concentration in the digested milk samples from Munich showed low values and the arithmetic mean values ranged between the quantification limit of 5 ng/L up to 65 ng/L. The median value amounted to 13 ng/L. The cerium concentrations in the Spanish breast milk samples amounted to similar low values. The data were about a factor of eight lower than values found in a former study of samples from an eastern German province. All cerium concentrations in the German plasma samples, except for two, were at the quantification limit of 10 ng/L. Interestingly, the serum samples of the Spanish mothers showed cerium values ranging between 21.6 and 70.3 ng/L; these higher data could be explained by an enhanced intake of cerium by humans in Madrid. This could be caused by increased cerium concentrations in particulate matter due to a higher traffic volume in Madrid compared to Munich. The results obtained in this study contribute to setting reference baseline values of cerium in human breast milk and blood plasma/serum and indicate a varying cerium amount depending on the cerium environmental pollution. Possibly, the cerium content in plasma/serum could be an indicator for environmental cerium, which is not valid for breast milk.

Effects of angiotensin-converting enzyme inhibitors (ACE i) on zinc metabolism in patients with heart failure.

The aim of this study is to investigate the effects of angiotensin-converting enzyme (ACE) inhibitors and furosemide on zinc metabolism by assessing serum zinc and urine levels in hospitalized subjects. We recruited 11 patients with heart failure from the Internal Medicine Department; these patients had been hospitalized less than 72 h before. Heart failure was defined using clinical and radiological signs. Serum zinc concentrations were measured using an air/acetylene flame atomic absorption spectrophotometer. Urine zinc levels were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Data were obtained from the 11 patients and 24 healthy controls matched for age and sex. Results indicate higher urine zinc levels and lower concentrations of zinc in serum in heart failure patients vs matched controls (p<0.05). This study suggests that treating heart failure patients with ACE inhibitors may result in zinc deficiency.