Analysis of Mercury Content in Various Types of Tea (Camellia sinensis) and Yerba Mate (Ilex paraguariensis)

Environmental and genetic predictors of whole blood mercury and selenium concentrations in pregnant women in a UK birth cohort

There is evidence that tissue concentrations of mercury (Hg) and selenium (Se) are predicted by numerous dietary, sociodemographic, environmental, and genetic factors. This study aimed to estimate the relative importance of predictors of Hg and Se concentrations in blood samples taken from pregnant women. The Avon Longitudinal Study of Parents and Children (ALSPAC) in the UK measured whole blood Hg and Se concentrations in 3,972 pregnant women. We identified 30 potential predictors of Hg and 24 of Se, which were evaluated using cross-validated random forests to identify the optimal models for predictive power. The relative importance of individual variables was estimated by averaging the added-R2 per predictor. Linkage disequilibrium score regression was used to estimate the variance explained by genotype. A multivariable model of 14 predictors explained 22.4% of Hg variance (95% CI: 13.0 to 37.1), including 6.9% from blood Se and 3.2% from white fish consumption. There were 11 predictors which explained 15.3% of Se variance (CI: 8.9 to 25.9), including 6.4% from blood Hg, 1.3% from blood lead, and 1.3% from oily fish. Measured genetic variation explained 30% of Hg variance (CI: 8.4 to 51.5) and 37.5% of Se (CI: 10.4 to 64.5). A high proportion of Hg and Se variance could be explained from dietary, sociodemographic, metabolic, and genetic factors. Seafood consumption was less predictive of Hg than may be expected and other factors should be considered when determining risk of exposure. There was tentative evidence that genotype is a major contributor to Hg and Se variation, possibly by modifying the efficacy of internal metabolism.

Do You Know What You Drink? Comparative Research on the Contents of Radioisotopes and Heavy Metals in Different Types of Tea from Various Parts of the World

The aim of this study was to assess the potential health risks of radioactive elements and heavy metals ingested through the consumption of various types of tea imported to the Polish market (black, green, red, oolong and white). The concentrations [Bq/kg] of radionuclides (40K, 137Cs, 226Ra, 210Pb and 228Th) in tea leaves before and after brewing were measured using γ-ray spectrometry with high-purity germanium (HPGe). The concentrations [mg/kg] of the studied elements (Fe, Cr, Cu, Mo, Al, Mn, Ni, P, V, Cd and Pb) were determined using a microwave-induced plasma optical emission spectrometer (MIP-OES). The results presented here will help to expand the database of heavy metals and radioactivity in teas. With regard to the potential health risk, the percentage of leaching of individual elements in different types of tea infusions was determined, and the assessment of the consumption risk was estimated. Since the calculated exposure factors, namely the HQ (Hazard Quotient) and THQ (Target Hazard Quotient), do not exceed critical levels, teas can still be considered health-beneficial products (most of the radionuclides as well as elements remain in the leaves (65-80%) after brewing).

Integrated genomics and transcriptomics reveal the extreme heavy metal tolerance and adsorption potentiality of Staphylococcus equorum

In this study, we successfully isolated 11 species of cadmium-tolerant bacterium from Pu-erh rhizosphere soil, of which Staphylococcus equorum PU1 showed the highest cadmium tolerance, with a minimum inhibitory concentration (MIC) value of 500 mg/L. The cadmium removal efficiency of PU1 in 400 mg/L cadmium medium reached 58.7 %. Based on the Nanopore PromethION and Illumina NovaSeq platforms, we successfully obtained the complete PU1 genome with a size of 2,705,540 bp, which encoded 2729 genes. We further detected 82 and 44 indel mutations in the PU1 genome compared with the KS1039 and KM1031 genomes from the database. Transcriptional analysis showed that the expression of 11 genes in PU1 increased with increasing cadmium concentrations (from 0 to 200, then to 400 mg/L), which encoded cadmium resistance, cadmium transport, and mercury resistance genes. In addition, some genes showed differential expression patterns with changes in cadmium concentration, including quinone oxidoreductase-like protein, ferrous iron transport protein, and flavohemoprotein. Gene Ontology (GO) functions, including oxidation reduction process and oxidoreductase activity functions, and KEGG pathways, including glycolysis/gluconeogenesis and biosynthesis of secondary metals, were also considered closely related to the extreme cadmium tolerance of PU1. This study provides novel insight into the cadmium tolerance mechanism of bacteria.

Long-term tea consumption reduces the risk of frailty in older Chinese people: Result from a 6-year longitudinal study

Background

Vast accumulative evidence suggests that the consumption of tea and its components have various potential health benefits. This study used a longitudinal study to examine the causality between tea consumption and frailty in older Chinese people.

Methods

This study employed the longitudinal data from 2008 to 2014 of the Chinese Longitudinal Healthy Longevity Survey (CLHLS), which were systematically collected through face-to-face interviews. Two thousand four hundred and seventy three participants completed six-follow-up surveys in 2014 and were analyzed in this study. The frailty index recommended by Searle and co-authors, including 44 health deficits, was used. A Generalized Estimating Equation (GEE) was applied to determine the risk ratio (RR) with a 95% confidence interval (CI) for frailty, and further subgroup analyses were conducted to investigate whether the risk differed stratified by age, sex, and socioeconomic status. Additionally, the interaction between tea consumption with sex and frailty was tested.

Results

Of the 2,473 participants, 14.1% were consistent daily tea drinkers, and 22.6% reported frailty at the 6-year follow-up. Compared to non-tea drinkers, consistent daily tea drinkers reported a significantly lower ratio of having frailty [risk ratio (RR) = 0.54, 95% confidence interval (CI): 0.38-0.78], adjusting for sociodemographic characteristics, health behavior, socioeconomic status, and chronic illnesses. In further subgroup analyses, consistent daily tea consumption significantly reduced the risk of frailty for males (RR = 0.53, 95% CI: 0.32-0.87) but not females (RR = 0.65, 95% CI: 0.37-1.12); in the young (RR = 0.40, 95% CI: 0.22-0.74) but not in the oldest (aged ≥ 80) (RR = 0.66, 95% CI: 0.40-1.06); informal education (RR = 0.48, 95% CI: 0.28-0.84) but not formal education (RR = 0.62, 95% CI: 0.37-1.03); financial dependence (RR = 0.42, 95% CI: 0.25-0.71) but not financial independence (RR = 0.71, 95% CI: 0.41-1.23). Additionally, females showed a lower tea-mediated risk of frailty in occasional tea consumers (RR = 0.51, 95% CI: 0.29-0.89) and inconsistent tea drinkers (RR = 0.58, 95% CI: 0.37-0.93).

Conclusions

Habitual tea consumption can reduce the risk of frailty in older Chinese, and the benefit varied by age, sex, education, and financial support.