Blood levels of lead, cadmium, and mercury in the elderly living in institutionalized care in the Czech Republic

Effects of mixed heavy metals on kidney function in premenopausal and postmenopausal women

OBJECTIVE

To evaluate the relationships between heavy metals (cadmium, lead, and mercury) and their mixtures and estimated glomerular filtration rate (eGFR) in premenopausal and postmenopausal women.

METHODS

Using data from the Korean National Health and Nutrition Examination Survey (2009-2017), multivariate linear regression models, marginal effects, and weighted quantile sum regression, we assessed the associations between single heavy metals and their mixtures and eGFR among 5,372 women.

RESULTS

Risks of reduced eGFR, comorbidities, and heavy metal exposure were found to be higher in postmenopausal women than in premenopausal women. A negative association of cadmium ( β = -2.97; 95% CI, -5.10 to -0.85) and a positive association of mercury ( β = 2.97; 95% CI, 1.49 to 4.44), with eGFR in postmenopausal women. Inverse associations of lead with eGFR in both premenopausal women ( β = -4.75; 95% CI, -6.04 to -3.46) and postmenopausal women ( β = -4.54; 95% CI, -6.96 to -2.13). Interactions were identified between lead and mercury, as well as cadmium and lead for eGFR among premenopausal women ( β = -2.04; 95% CI, -2.98 to -1.10) and postmenopausal women ( β = -3.52; 95% CI, -6.04 to -1.01), respectively. There was a negative association between mixed heavy metals and eGFR in both premenopausal women ( β = -2.23; 95% CI, -3.51 to -0.96) and postmenopausal women ( β = -3.86; 95% CI, -6.89 to -0.83). Lead was found as a key chemical related to reduced eGFR. Cutoff values for each heavy metal concentration related to eGFR were provided.

CONCLUSION

Postmenopausal women were more influenced by mixed heavy metals' effects on kidney function than premenopausal women. Early interventions (eg, water filtering, heavy metal yearly screening) in women, especially postmenopausal women, are needed to reduce the incidence of chronic kidney disease.

Effects of Low-Level Organic Mercury Exposure on Oxidative Stress Profile

Background: The fish-based diet is known for its potential health benefits, but it is less known for its association with mercury (Hg) exposure, which, in turn, can lead to neurological and cardiovascular diseases through the exacerbation of oxidative stress. The aim of this study was to evaluate the correlations between Hg blood concentration and specific biomarkers for oxidative stress. Methods: We present a cross-sectional, analytical, observational study, including primary quantitative data obtained from 67 patients who presented with unspecific complaints and had high levels of blood Hg. Oxidative stress markers, such as superoxide dismutase (SOD), glutathione peroxidase (GPX), malondialdehyde (MLD), lymphocyte glutathione (GSH-Ly), selenium (Se), and vitamin D were determined. Results: We found positive, strong correlations between Hg levels and SOD (r = 0.88, p < 0.0001), GPx (r = 0.92, p < 0.0001), and MLD (r = 0.94, p < 0.0001). We also found inverted correlations between GSH-Ly and vitamin D and Hg blood levels (r = −0.86, r = −0.91, respectively, both with p < 0.0001). Se had a weak correlation with Hg plasma levels, but this did not reach statistical significance (r = −0.2, p > 0.05). Conclusions: Thus, we can conclude that low-level Hg exposure can be an inductor of oxidative stress.

Environmental Exposure to Metals, Parameters of Oxidative Stress in Blood and Prostate Cancer: Results from Two Cohorts

We studied the potential role of exposure to various metal(oid)s (As, Cd, Cr, Hg, Ni, and Pb) in prostate cancer. Two cohorts were established: the Croatian cohort, consisting of 62 cases and 30 controls, and the Serbian cohort, consisting of 41 cases and 61 controls. Blood/serum samples were collected. Levels of investigated metal(oid)s, various parameters of oxidative stress, and prostate-specific antigen (PSA) were determined in collected samples. A comparison of the measured parameters between 103 prostate cancer patients and 91 control men from both Croatian and Serbian cohorts showed significantly higher blood Hg, SOD, and GPx levels and significantly lower serum SH levels in prostate cancer patients than in controls. Correlation analyses revealed the significant relationship between certain parameters of oxidative stress and the concentrations of the measured metal(loid)s, pointing to the possible role of metal(oid)-induced oxidative stress imbalance. Furthermore, a significant inverse relationship was found between the blood Pb and the serum PSA in prostate cancer patients, but when the model was adjusted for the impacts of remaining parameters, no significant association between the serum PSA and the measured parameters was found. The results of the overall study indicate a substantial contribution of the measured metal(loid)s to the imbalance of the oxidant/antioxidant system. Although somewhat conflicting, the results of the present study point to the possible role of investigated metal(oid)s in prostate cancer, especially for Hg, since the obtained relationship was observed for both cohorts, followed by the disturbances in oxidative stress status, which were found to be correlated with Hg levels. Nevertheless, further studies in larger cohorts are warranted to explain and confirm the obtained results.

Toxic Metals and Chronic Kidney Disease: a Systematic Review of Recent Literature

PURPOSE OF REVIEW

Arsenic (As), cadmium (Cd), and lead (Pb) are ubiquitous toxicants with evidence of adverse kidney impacts at high exposure levels. There is less evidence whether environmental exposure to As, Cd, or Pb plays a role in development of chronic kidney disease (CKD). We conducted a systematic review to summarize the recent epidemiologic literature examining the relationship between As, Cd, or Pb with CKD.

RECENT FINDINGS

We included peer-reviewed studies published in English between January 2013 and April 2018 for As and Cd, and all dates prior to April 2018 for Pb. We imposed temporality requirements for both the definition of CKD (as per NKF-KDOQI guidelines) and environmental exposures prior to disease diagnosis. Our assessment included cohort, case-control or cross-sectional study designs that satisfied 5 inclusion criteria. We included a total of eight articles of which three, two, and four studies examined the effects of As, Cd, or Pb, respectively. Studies of As exposure consistently reported positive association with CKD incidence; studies of Pb exposure were mixed. We found little evidence of association between Cd exposure and CKD. Additional well-designed prospective cohort studies are needed and we present recommendations for future studies.

Complex effects of pollution on fish in major rivers in the Czech Republic

Monitoring the contamination level in aquatic environments and assessing the impact on aquatic life occurs throughout the world. In the present study, an approach based on a combination of biomarkers and the distribution of various industrial and municipal pollutants was used to investigate the effect of aquatic environmental contamination on fish. Monitoring was performed in ten rivers in the Czech Republic (Berounka, Dyje, Elbe, Lužnice, Odra, Ohře, Otava, Sázava, Svratka, and Vltava rivers, with one or two locations in each river) at the same sites that were regularly monitored within the Czech National Monitoring Program in 2007-2011. Health status, hepatic ethoxyresorufin-O-deethylase (EROD) activity, total cytochrome P450 content, and the plasma vitellogenin concentration were assessed in wild chub (Squalius cephalus) males caught at the monitored sites. The contamination level was the highest in the Svratka River downstream of Brno. Among all measured persistent organic pollutants (POPs), polychlorinated biphenyls and dichlorodiphenyltrichloroethane and its metabolites were the major contributors of POPs in fish muscle. Elbe, Odra, and Svratka rivers were identified as the most polluted. Fish from these locations showed reduced gonad size, increased vitellogenin concentration in male plasma, EROD, and total cytochrome P450 content. These biomarkers can be used for future environmental monitoring assessments. Overall, this study improves our understanding of the relationship between human activities and pollutant loads and further contributes to the decision to support local watershed managers to protect water quality in this region.

Analysis of the relationship between the blood concentration of several metals, macro- and micronutrients and endocrine disorders associated with male aging

Beyond 30 years of age, men experience a decline in the production of testosterone, yet only a few develop late-onset hypogonadism. This study was designed to determine the relationship between blood concentrations of metals, macro- and micronutrients and age-related testosterone deficiency and associated hormonal changes in aging men. The research involved 313 men aged 50-75 years. We used ELISA to determine the concentrations of total testosterone (TT), free testosterone (FT), estradiol (E2), dehydroepiandrosterone sulfate (DHEAS) and sex hormone-binding globulin (SHBG). We calculated free androgen index (FAI). With the use of emission spectrometry in inductively coupled argon plasma, we determined the whole-blood concentrations of lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As) and tungsten (W), as well as serum concentrations of magnesium (Mg), iron (Fe), calcium (Ca), copper (Cu), zinc (Zn), selenium (Se), chromium (Cr), manganese (Mn) and molybdenum (Mo). The study showed no relationship between TT and FT and the concentrations of metals. Men with TT deficiency had significantly lower concentrations of Mg and Fe and increased Mn. Men with FT deficiency had higher W and Cr levels and lower Fe. Assessing the correlation between the concentrations of hormones, SHBG and FAI, and the concentration of metals and macro- and microelements in the blood of the men, we found positive correlations between the concentrations of TT-Mg, TT-Fe, TT-Mo, FT-Fe, E2-As, SHBG-Mn, FAI-W, FAI-As, FAI-Zn and FAI-Ca, and negative correlations between the concentrations of TT-Mn, FT-Cd, FT-Cr, E2-Hg, E2-Cr, SHBG-W, SHBG-As, SHBG-Zn, SHBG-Ca, FAI-Pb and FAI-Mn. Positive correlations between As and E2 and between As and FAI may suggest a lack of association between this metal and hypogonadism in people not exposed to excess As levels. Our research indicates a positive relationship between the concentrations of Mg, Fe and Zn and endocrine system in aging men, in contrast to Mn and Cr. Toxic metals (Cd, Pb) seemed to negatively affect the level of bioavailable testosterone. In persons not exposed to As, As does not contribute late-onset hypogonadism. Heavy metals (Pb, Cd, Hg and W) may contribute to a lower concentration of DHEAS. The role of W in men with LOH was found to be ambiguous, as on the one hand its concentration was higher in men with FT deficiency, and on the other hand it positively correlated with FAI, which in turn indirectly indicates testosterone availability. Copper and selenium do not seem to play any significant role in the occurrence of TT deficiency in aging men.

Urinary stones as a novel matrix for human biomonitoring of toxic and essential elements

Monitoring of body burden of toxic elements is usually based on analysis of concentration of particular elements in blood, urine and/or hair. Analysis of these matrices, however, predominantly reflects short- or medium-term exposure to trace elements or pollutants. In this work, urinary stones were investigated as a matrix for monitoring long-term exposure to toxic and essential elements. A total of 431 samples of urinary calculi were subjected to mineralogical and elemental analysis by infrared spectroscopy and inductively coupled plasma mass spectrometry. The effect of mineralogical composition of the stones and other parameters such as sex, age and geographical location on contents of trace and minor elements is presented. Our results demonstrate the applicability of such approach and confirm that the analysis of urinary calculi can be helpful in providing complementary information on human exposure to trace metals and their excretion. Analysis of whewellite stones (calcium oxalate monohydrate) with content of phosphorus <0.6 % has been proved to be a promising tool for biomonitoring of trace and minor elements.