Μg Day Research Articles

Investigation of thallium as a contaminant in dietary supplements marketed for weight loss and physical fitness

Dietary supplements are drastically growing as a category of consumer products all over the world. The abuse of supplements marketed for slimming purposes and physical fitness has been observed worldwide in recent years, which raises concerns in terms of public health. In this study, different types of dietary supplements marketed and delivered through the e-commerce were studied for the determination of thallium as a hazardous inorganic contaminant. The total content of thallium was determined by a sensitive voltammetric method after a microwave-assisted oxidative digestion of the sample. In addition, a comparative spectrometric method was applied for validation of the results in the samples. The maximum concentration found for thallium was found to be 2.89 mg kg−1, which well agree with the comparative measurement. Considering the 32 studied formulations, it can be pointed out that ∼24% of the of dietary supplements presented Tl concentrations at concentrations higher than 1 mg kg−1. The results permitted the assessment of the health risk related to thallium from contaminated samples, based on the calculation of the estimated daily intake (EDI) and the risk quotient (HQ). The highest daily intake of thallium was calculated as 82.0 µg day−1 in a protein-based supplement, which is equivalent to an EDI of 1.17 µg kg−1 day−1. This work highlights the need to develop regulations on the limits of toxic elements such as thallium in widely consumed dietary supplements, as well as an in-depth look at the adverse effects caused by this element in the human body.

Concentrations and probable health risks of potentially toxic metals (Pb, Cd and Cr) in some Nigerian lipstick products

BackgroundLipstick is one of the widely used cosmetic items that are produced from both natural and processed materials and they are one of the sources of metals and metalloids released among the users. This study measured concentrations of Pb, Cd and Cr in some brands of Nigerian lipstick products and assessed their probable health risks to the users. MethodsA total of twenty (L1 - L20) brands of lipstick products were purchased from the central cosmetic stores and the samples were prepared, digested and concentrations of Pb, Cd and Cr were determined using Atomic Absorption Spectrometry (AAS). The probable health risk was assessed via average daily dose (ADD) by ingestion route, hazard quotient (HQ), hazard index (HI), cancer risks (CR), and relative intake index (RII). ResultsThe ranges of concentrations of Pb, Cd and Cr were 5.6 - 25.1, 2.5 - 21.5 and 5.0 - 61.7 μg g−1, respectively. The ranges of ADD values of Pb, Cr and Cd were 1.2 × 10−3 - 5.7 × 10−3; 1.3 × 10−3 - 5.7 × 10−3 and 5.1 × 10−3 - 1.4 × 10−3 µg day−1, respectively. Among the samples Cr had HQ values 1.3 to 9.6. The HQ values of Cd for L2, L6, L12 and L14 ranges between 1.1 and 1.5. Then HQ values of Pb for L1 -L20 were 1.0 - 4.1. The HI values of Pb, Cr and Cd in each lipstick brands range from 2.8 to 12.5, indicating a non-carcinogenic health risk. The CR values for Cr and Cd are from 6.6 × 10−4 to 6.9 × 10−4 and from 2.0 × 10−2 to 2.5 × 10−2, respectively and they were within the acceptable limit value of 1.0 × 10−4. The RII of Pb, Cd and Cr were 4.50 - 20.1, 2.0 – 19.2 and 1.9 – 23.0 %, respectively. ConclusionAll the health indices indicated non-carcinogenic health risks. The continuous exposure and unintentional ingestion of such lipstick products can pose high risks to the users due to bioaccumulation of Pb, Cd and Cr which may lead to negative health conditions.

Nutritional profile and risk assessment of inorganic elements in enteral and parenteral nutrition formulas

The contents of essential (Ca, Fe, K, Na, P, and Zn) and potentially toxic inorganic elements (As, Al, Cd, Cr, Cu, Mn, and Pb) in enteral and parenteral nutrition formulas were evaluated by inductively coupled plasma optical emission spectrometry (ICP OES) and graphite furnace atomic absorption spectrometry (GFAAS). A total of 30 enteral formulas, 23 parenteral solution components, and 3 parenteral solutions were analyzed. The elements Ca and K presented the higher contents (72–2918 mg L−1 and 235–2760 mg L−1) while the lowest concentration levels were found for As and Cd (<0.68 µg L−1 and <0.01–0.62 µg L−1) in the studied samples. The validated analytical methods presented an accuracy of 75–116% and RSD values lower than 9.8%. Calcium gluconate and magnesium sulfate, which are used as raw materials in parenteral solution, are potential sources of Al and Mn contamination. A Hazard Quotient (HQ) >1 was obtained for Al (27 ± 1 µg L−1) in one of the parenteral samples, whereas the established limit is 25 µg L−1. Enteral samples were considered safe for consumption regarding the Al, As, and Cd levels. One healing-specific and pediatric formula contained Pb at levels above 0.25 µg kg-day−1, too high for safe consumption. The enteral formulas (pediatric, diabetes-specific, renal-specific, healing-specific, and standard formula with addition of fiber) presented risks in relation to the consumption of Cr and Mn (>250 µg day−1 and >11 mg day−1). The results indicate the need for strict monitoring, considering that these formulations are often the single patient’s food source.

Sources, size-resolved deposition in the human respiratory tract and health risks of submicron black carbon in urban atmosphere in Pearl River Delta, China

Black carbon (BC) has a significantly negative impact on air quality, climate and human health. Here we investigated the sources and health effects of BC in urban area of the Pearl River Delta (PRD) based on online data measured by Aerodyne soot particle high-resolution time of flight aerosol mass spectrometer (SP-AMS). In urban PRD, BC particles mainly came from vehicle emissions especially heavy-duty vehicle exhausts (contributing 42.9 % of total BC mass concentration), long-range transport (27.6 %), and aged biomass combustion emissions (22.3 %). Indicated by source analysis using simultaneous aethalometer data, BC associated with local secondary oxidation and transport may also be originated from fossil fuel combustion, especially traffic sources in urban and surrounding areas. Size-resolved BC mass concentrations provided by SP-AMS, for the first time to our best knowledge, were used to calculate BC deposition in the human respiratory tract (HRT) of different populations (children, adults, and the elderly) by the Multiple-Path Particle Dosimetry (MPPD) model. We found that submicron BC was deposited more in the pulmonary (P) region (49.0–53.2 % of the total BC deposition dose), while less in the tracheobronchial (TB, 35.6–37.2 %) and head (HA, 11.2–13.8 %) regions. Adults suffered the highest BC deposition (1.19 μg day−1) than the elderly (1.09 μg day−1) and children (0.25 μg day−1). BC deposition rate was greater at night (especially 18:00–24:00) than during the daytime. The maximum deposition in the HRT was found for BC particles around 100 nm, mainly in deeper respiratory regions (TB and P), which may cause more serious health effects. Adults and the elderly group are confronted with the notable carcinogenic risk of BC in the urban PRD, up to 29 times higher than the threshold. Our study emphasizes the need to control BC pollution in the urban area, especially nighttime vehicle emissions.

Iodine in plant-based dairy products is not sufficient in the UK: A market survey

BackgroundFollowing a well-balanced diet ensures that a person gets all the essential elements for health sustenance. However, in the United Kingdom an increasing proportion of people are transiting to become vegans who exclude animal-based products in their diets. Consequently, people may have a deficit of essential elements such as iodine which is not present in most plant-based meals, additionally iodide fortified table salt is not commonly used in the UK. Without iodine people consuming a vegan diet risk developing iodine deficiency and diseases like goiter. MethodsThe objective of this study is to determine the difference in iodine content and iodine speciation between plant-based and dairy products. More than 100 market samples of plant-based and dairy milk products were collected in Scotland, UK. ResultsIodine concentrations in dairy milk is ten times higher compared to plant-based milks. Similar differences were also apparent for butter, yogurt and cheese. A total of 20% of plant-based milk products were fortified with iodine, however these products had lower iodine concentrations compare to the equivalent dairy products. In this study we calculated that people with average diet have an iodine intake of 226 + /- 103 μg day−1 from dairy products which satisfies the WHO recommended intake of adults and 90% of the recommend intake for pregnant and breast-feeding women. A diet from substituted dairy products gives only 21.8 µg day−1 for the respective WHO guideline intake values, which accounts only 15% of the iodine intake for adults and 9% for pregnant and lactating women. Iodine fortified diet could increase the iodine intake to 55% or 33% of the WHO recommended daily intake respectively. ConclusionPlant-based dairy consumers are encouraged to use iodine fortified dairy products or use of iodized salt in the UK for home cooking, otherwise there are at risk to get iodine deficient.

Copper Concentrations Found from Drinking Water, Soils, and Vegetables

Humans, animals, and plants need copper for growth and development, but it can be an irritant to humans. The daily maximum limit of copper for humans is 10-12 µg day^-1 and excess concentrations of copper can cause nausea, diarrhea, and anorexia. In plants, excess copper concentrations cause chlorosis, stunted growth, and denaturing of macromolecules. Only 10 mg kg^-1 of copper can be accumulated by plants. The maximum allowable concentration in agricultural soils is 6.6 mg kg^-1. The concentration of copper in drinking water should not exceed 1 mg L^-1. When copper concentrations exceed an action level of 1.3 ppm in more than 10% of customer taps sampled, several additional controlling measures must be undertaken. In waste, the allowable concentration is 16 mg kg^-1. The hypothesis of the study was that copper would be found in the vegetables grown from the agricultural soils. Cabbage, green pepper, spinach, and tomato were grown for thirteen weeks. The soil and vegetables were digested, and the copper concentrations were measured using an Atomic Absorption Spectroscopy (AAS). The highest total and extractable copper concentrations found in the soil were 73 mg kg^-1 and 26 mg kg^-1, respectively. More than 20 and 32 mg kg^-1 of copper was found in the shoot and roots of the vegetables, respectively. More than 11 mg L^-1 of copper was found in the tap water. The results indicated that the copper concentrations from the soil, water, and vegetables exceeded the allowable concentrations.

Associations of dietary factors and xenobiotic intake with faecal microbiota composition according to the presence of intestinal mucosa damage.

Diet is a major modulator of gut microbiota, which plays a key role in the health status, including colorectal cancer (CRC) development. Several studies and meta-analyses have evidenced an association of certain dietary factors and xenobiotic intake with the incidence of CRC. Nevertheless, how these dietary factors impact the first stages of intestinal mucosa damage is still uncertain. This study aimed at exploring the associations of relevant dietary factors with the gut microbiota of control individuals and subjects diagnosed with intestinal polyps. A total of 60 volunteers were recruited, clinically classified according to colonoscopy criteria and interviewed using food frequency questionnaires (FFQs). The nutritional status of each volunteer was determined and the intake of dietary xenobiotics was quantified. The relative abundance of faecal microbiota taxonomic groups was obtained through 16S rRNA gene sequencing. The association of dietary factors and xenobiotics with faecal microbiota composition showed differences according to the clinical diagnosis group. Our results showed that the intake of red meat (≥50 g day-1) and total polycyclic aromatic hydrocarbons (PAHs) (≥0.75 μg day-1) was associated with a decreased abundance of the family Bacteroidaceae and an increased abundance of Coriobacteriaceae in control subjects. The intake of the heterocyclic amines 2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine (PhIP) (≥40 ng day-1) and 2-amino-3,8 dimethylimidazo(4,5,f) quinoxaline (MeIQx) (≥50 ng day-1) was associated with a decreased abundance of Akkermansiaceae in the control diagnosis group. Moreover, N-nitroso compounds (NOCs), nitrites (≥1.69 mg day-1) and N-nitrosodimethylamine (NDMA) (≥0.126 μg day-1) were associated with a decreased abundance of Bifidobacteriaceae. The intake of ethanol (≥12 g day-1) in the polyps group was associated with an increased abundance of Peptostreptococcaceae and a decreased abundance of Veillonellaceae. Moreover, linear regression analyses allowed us to identify ethanol, calcium, bioactive compounds such as flavonoids, stilbenes, cellulose, phenolic acids or total polyphenols, and dietary xenobiotics such as PhIP and MeIQx, the NOC N-nitrosopyrrolidine (NPYR) or the total PAHs as potential predictors of faecal microbiota group abundances. These results indicated that the consumption of milk, red meat, processed meat and ethanol and the intake of polyphenols, dietary PAHs, HAs and NOCs are associated with specific groups of the intestinal microbiota, depending on the clinical diagnosis group.

Zinc biofortification of Genovese basil: Influence on mineral profile and estimated daily intake in adults and children

Despite the well-known beneficial function of Zn in human health, its deficiency is an increasingly recognized worldwide concern. In this work, we evaluated the agronomic biofortification of two basil (Ocimum basilicum L.) cultivars (‘Aroma 2’ and ‘Eleonora’) using nutrient solutions with different Zn concentrations (0, 12.5, 25, 37.5, and 50 µM). We focused on the impact of biofortification on the mineral profile quantified by ICP OES. Compared to the control, biofortification treatments increased Zn concentration by 22.03 % (on average). Consumption of one serving of 50 µM of Zn biofortified basil ‘Aroma 2’ guarantees an estimated daily intake (EDI) of 275.746 and 91.915 µg day−1 in adults and children, respectively. Furthermore, Zn biofortification positively affected the mineral profile of the leaves. Compared to the control, the B50 dose of Zn (50 μM of Zn) increased the EDI of macro and microelements in adults and children. This aspect highlights how biofortified basil consumption would improve consumers’ nutritional status.

Volatile Compound Emissions from Stereolithography Three-Dimensional Printed Cured Resin Models for Biomedical Applications.

Stereolithography three-dimensional printing is used increasingly in biomedical applications to create components for use in healthcare and therapy. The exposure of patients to volatile organic compounds (VOCs) emitted from cured resins represents an element of concern in such applications. Here, we investigate the biocompatibility in relation to inhalation exposure of volatile emissions of three different cured commercial resins for use in printing a mouthpiece adapter for sampling exhaled breath. VOC emission rates were estimated based on direct analysis using a microchamber/thermal extractor coupled to a proton transfer reaction-mass spectrometer. Complementary analyses using comprehensive gas chromatography-mass spectrometry aided compound identification. Major VOCs emitted from the cured resins were associated with polymerization agents, additives, and postprocessing procedures and included alcohols, aldehydes, ketones, hydrocarbons, esters, and terpenes. Total VOC emissions from cubes printed using the general-purpose resin were approximately an order of magnitude higher than those of the cubes printed using resins dedicated to biomedical applications at the respective test temperatures (40 and 25 °C). Daily inhalation exposures were estimated and compared with daily tolerable intake levels or standard thresholds of toxicological concerns. The two resins intended for biomedical applications were deemed suitable for fabricating an adapter mouthpiece for use in breath research. The general-purpose resin was unsuitable, with daily inhalation exposures for breath sampling applications at 40 °C estimated at 310 μg day-1 for propylene glycol (tolerable intake (TI) limit of 190 μg day-1) and 1254 μg day-1 for methyl acrylate (TI of 43 μg day-1).

Potential exposure and risk assessment of agricultural workers to the insecticide chlorantraniliprole in rice paddies.

Exposure of agricultural workers in rice paddies to the insecticide chlorantraniliprole and its subsequent potential health risks were investigated during two scenarios (mixing/loading and hand-held spraying). The exposure factors, such as the outer dosimeter, inner dosimeter, gauze, and nitrile gloves, were calculated using whole-body dosimetry to measure dermal exposure. The inhalation exposure was determined using a fiberglass filter which is set with an Institute of Occupational Medicine (IOM) sampler. A recovery test was performed to evaluate the accuracy of the analytical method. The exposure amounts of various matrices were calculated from extraction volume and concentration of the target compound. The dermal exposure to chlorantraniliprole was 0.6mg [0.001% of the total active ingredient (a.i.)] for mixing and loading, and 28.6mg (0.066% of the total a.i.) for application. The inhalation exposure to chlorantraniliprole was 7.2μg (1.3%, 1.2 × 10-5 % of the total applied a.i.) for mixing and loading, and 1.9μg (0.006%, 4.4 × 10-6 % of the total applied a.i.) for application. The most exposed part of the body was the hand (90.4%) during mixing and loading, whereas the primary sites during application were the thighs (32.8%) and shins (22.6%). For mixing and loading, the amount of actual dermal exposure was 5.5μg day-1 and that of actual inhalation exposure was 21.9μg day-1 . By contrast, in the application, the amounts of actual dermal and actual inhalation exposures were 34 178.7 and 5.9μg day-1 , respectively. The risk assessment results demonstrated that the risk of chlorantraniliprole exposure in rice paddies was low during application than during mixing and loading. © 2022 Society of Chemical Industry.

Effect of vitamin D3 supplementation on cardiometabolic disease risk among overweight/obese adult males in the UK: A pilot randomised controlled trial.

Observational studies suggest links between reduced serum 25(OH)D concentration and increased cardiometabolic disease risk. However, these studies provide limited evidence of causation, with few conclusive randomised controlled trials (RCT) having been carried out to date. This RCT investigated the effect of vitamin D3 supplementation on vascular function and cardiometabolic disease risk markers, in 55 healthy males aged 18-65 years with plasma 25(OH)D concentration <75 mol L-1 and body mass index ≥24.9 kg m-2 . Participants were assigned to consume 125 µg day-1 (5000 IU day-1 ) vitamin D3 or placebo for 8 weeks. Blood samples and vascular function measures were obtained at baseline, as well as at weeks 4 and 8. The primary outcome was arterial stiffness, an indicator of cardiovascular disease (CVD) risk, assessed by pulse wave velocity. Biomarkers of CVD risk, insulin resistance and endothelial function were measured using an enzyme-linked immunosorbent assay. Daily oral intake of 125 µg supplemental vitamin D3 led to a significant improvement in plasma 25(OH)D concentrations over the 8-week intervention in the vitamin D group compared to the change in the placebo group (p ˂ 0.001). In the vitamin D group, the baseline mean ± SD 25(OH)D concentration was 38.4 ± 15.9 and this increased to 72.8 ± 16.1 nmol L-1 after 8 weeks of supplementation. The intervention had no effect on arterial stiffness, as measured by pulse wave velocity, although vitamin D3 supplementation did lead to a decrease in mean ± SD brachial pulse pressure from baseline to 8 weeks of -2.9 ± 3.4 mmHg (p = 0.027) in the vitamin D group compared to the same period in the placebo group. The intervention had no effect on the remaining cardiometabolic parameters. Overall, treatment significantly improved brachial pulse pressure but no other cardiometabolic disease risk markers. To follow on from this pilot RCT, future large-scale clinical trials over longer durations may offer further insights.

Evidence of low vitamin D intakes in the Australian population points to a need for data-driven nutrition policy for improving population vitamin D status.

Nearly one in four Australian adults is vitamin D deficient (serum 25-hydroxyvitamin D concentrations [25(OH)D] <50 nmolL-1 ) and current vitamin D intakes in the Australian population are unknown. Internationally, vitamin D intakes are commonly below recommendations, although estimates generally rely on food composition data that do not include 25(OH)D. We aimed to estimate usual vitamin D intakes in the Australian population. Nationally representative food consumption data were collected for Australians aged ≥2years (n = 12,153) as part of the cross-sectional 2011-2013 Australian Health Survey (AHS). New analytical vitamin D food composition data for vitamin D3 , 25(OH)D3 , vitamin D2 and 25(OH)D2 were mapped to foods and beverages that were commonly consumed by AHS participants. Usual vitamin D intakes (µgday-1 ) by sex and age group were estimated using the National Cancer Institute method. Assuming a 25(OH)D bioactivity factor of 1, mean daily intakes of vitamin D ranged between 1.84 and 3.25 µgday-1 . Compared to the estimated average requirement of 10 µgday-1 recommended by the Institute of Medicine, more than 95% of people had inadequate vitamin D intakes. We estimated that no participant exceeded the Institute of Medicine's Upper Level of Intake (63-100 µgday-1 , depending on age group). Usual vitamin D intakes in Australia are low. This evidence, paired with the high prevalence of vitamin D deficiency in Australia, suggests that data-driven nutrition policy is required to safely increase dietary intakes of vitamin D and improve vitamin D status at the population level.

Imbalanced Folate and Vitamin B12 in the Third Trimester of Pregnancy and its Association with Birthweight and Child Growth up to 2 Years.

Folic acid supplementation during pregnancy may lead to an imbalance when vitamin B12 intake is low (folate trap) and may affect child's growth. The authors study the association between third trimester maternal intakes of folate and B12 and birthweight and postnatal growth of 2632 infants from the KOALA Birth Cohort Study. Plasma vitamin biomarkers are measured in 1219 women. Imbalanced total intakes (folate >430µg day-1 combined with B12 <5.5µg day-1 ) are not associated with birthweight [β adj (95% CI) = -14.87 (-68.87, 39.13)]compared with high intakes of both.Imbalanced intake is associated with a lower z score of weight at 1-2 years [β adj = -0.14 (-0.25, -0.03)].Having red blood cell folate >745nmol L-1 and plasma B12 <172pmol L-1 is not associated with birthweight [β adj = -7.10 (-97.90, 83.71) g].Maternal dietary B12 intake[β adj = -9.5 (-15.6, -3.3)] and plasma methylmalonic acid [β adj = 234 (43, 426)] are associated with birthweight. Low maternal dietary B12 intake and elevated methylmalonic acid rather than imbalanced vitamins are associated with higher birthweight, suggesting thatlow maternal B12 can predispose the infants for later obesity.

Selenium Enrichment of Green and Red Lettuce and the Induction of Radical Scavenging Potential

Selenium (Se)-enriched vegetables are promising dietary sources of Se, which provides beneficial biological effects in humans. In this study, we investigated the effects of foliar application of Se on hydroponically grown multi-leaf green (V1) and red (V2) lettuce plants. Three selenate (SeIV) amendment levels were evaluated for their influence on plant growth, elemental composition and radical scavenging capacity. Lettuce heads biofortified with 0.598 mg Se plant−1 accumulated 19.6–23.6 and 14.9–17.6 μg Se g−1 DM in the multi-leaf green (V1) and red (V2) lettuce plants, respectively. The accumulated Se levels can contribute significantly to the recommended dietary allowance of 70 µg day−1 for adult men and 60 µg day−1 for adult women. Accordingly, both V1 and V2 lettuce cultivars grown under the Se3 foliar application condition can cover the daily requirement for adult men by approximately 100% and 85% to 100%, respectively, by consuming 75–90 g or 100 g fresh weight from V1 or V2, respectively. The ABTS radical scavenging potential of green lettuce was induced at Se2 and Se3 foliar application levels, where the IC50 was 1.124 ± 0.09 μg mL−1 at Se0 and improved to 0.795 ± 0.03 and 0.697 ± 0.01 μg mL−1, respectively. There was no cytotoxicity against Vero kidney cells among all treated lettuce plants at the highest concentration tested of 1 mg/mL. Finally, a further focused investigation of the metabolic profile of lettuce plants under varied Se levels needs to be investigated in future studies.

Distinct uptake and accumulation profiles of triclosan in youdonger (Brassica campestris subsp. Chinensis var. communis) under two planting systems: Evidence from 14C tracing techniques

Triclosan is a widely used biocide against microorganisms and is ubiquitously distributed in the environment. Triclosan can be accumulated into plants from soil and hydroponic media. However, little information is currently available on the comparative fate of triclosan in plants under soil and hydroponics cultivation conditions and factors governing uptake. Therefore, this study was designed to comparatively elucidate the uptake mechanism of 14C-triclosan in youdonger (Brassica campestris subsp. Chinensis var. communis) grown under different soils and hydroponics and clarify dominant uptake factors. Results showed that 77.2% of 14C were accumulated in youdonger grown in a hydroponic system, while only 1.24%–2.33% were accumulated in the two soil-planting systems. In addition, the bioconcentration factor (BCF) of 14C-triclosan in soil-plant systems was approximately 400-fold smaller than that in the hydroponics. In the soil-planting system, a strong linear correlation was found between concentrations of triclosan in soil pore water and youdonger plant (R2 > 0.85, p < 0.01) at different incubation times. Therefore, triclosan in pore water might be a good indicator to estimate its accumulation in plants and is significantly affected by soil pH, clay, and organic matter contents. The estimated average dietary intakes of triclosan for youdonger grown in hydroponic and soil-planting systems were estimated to be 1.31 ng day−1 kg−1 and 0.05–0.12 ng day−1 kg−1, respectively, much lower than the acceptable dietary intakes of triclosan (83 μg day−1 kg−1), indicating no significant human health risks from youdonger consumption. This study provided insights into uptake routes of triclosan into youdonger plants from both soil and hydroponic systems, bioavailability of triclosan in different soils, and further assessment of human exposure to triclosan from youdonger.

Assessment and mitigation of toddlers’ personal exposure to black carbon before and during the COVID-19 pandemic: A case study in Singapore

Black carbon (BC), an important indicator of traffic-related air pollution (TRAP) in urban environments, is receiving increased attention because of its adverse health effects. Personal exposure (PE) of adults to BC has been widely studied, but little is known about the exposure of young children (toddlers) to BC in cities. We carried out a pilot study to investigate the integrated daily PE of toddlers to BC in a city-state with a high population density (Singapore). We studied the impact of urban traffic on the PE of toddlers to BC by comparing and contrasting on-road traffic flow (i.e., volume and composition) in Singapore in 2019 (before the COVID-19 pandemic) and in 2020 (during the COVID-19 pandemic). Our observations indicate that the daily BC exposure levels and inhaled doses increased by about 25% in 2020 (2.9 ± 0.3 μg m−3 and 35.5 μg day−1) compared to that in 2019 (2.3 ± 0.4 μg m−3 and 28.5 μg day−1 for exposure concentration and inhaled dose, respectively). The increased BC levels were associated with the increased traffic volume on both weekdays and weekends in 2020 compared to the same time period in 2019. Specifically, we observed an increase in the number of trucks as well as cars/taxis and motorcycles (private transport) and a decline in the number of buses (public transport) in 2020. The implementation of lockdown measures in 2020 resulted in significant changes in the time, place and duration of PE of toddlers to BC. The recorded daily time-activity patterns indicated that toddlers spent almost all the time in indoor environments during the measurement period in 2020. When we compared different ventilation options (natural ventilation (NV), air conditioning (AC), and portable air cleaner (PAC)) for mitigation of PE to BC in the home environment, we found a significant decrease (>30%) in daily BC exposure levels while using the PAC compared to the NV scenario. Our case study shows that the PE of toddlers to BC is of health concern in indoor environments in 2020 because of the migration of the increased TRAP into naturally ventilated residential homes and more time spent indoors than outdoors. Since toddlers’ immune system is weak, technological intervention is necessary to protect their health against inhalation exposure to air pollutants.

Determination of Endocrine-Disrupting Nonylphenols and Nonylphenol Carboxylates by High-Performance Liquid Chromatography-Tandem Mass Spectrometry: Levels in German Food after Restriction

Nonylphenols (NPs) and nonylphenol carboxylates (NPECs) are products of the biodegradation of nonylphenol ethoxylates (NPEOs), which is a widely used group of nonionic surfactants. These compounds are persistent, toxic, and exhibit estrogenic activity. Global scientific and public discourse has revealed the consequences of long-term dietary exposure to these endocrine disrupters. Since 2005, the utilization and sale of NPEOs and NPs have been regulated in some industrial applications by Directive 2003/53/EC of the European Union (EU). The objective of this investigation was to assess the NPs and NPECs concentration levels in foodstuffs following the implementation of the EU directive. Using a method based on high-performance liquid chromatography combined with tandem mass spectrometry (HPLC-MS), NPs and NPECs were determined in the same German food basket that was examined before the restriction. NPs were detected in 22 of the 24 food samples, whereas NPECs were below the limit of detection. The concentrations of NPs on a fresh weight basis varied between 0.1 and 6.3 μg kg−1. Based on the data of food consumption rates in Germany and the concentrations of NPs in the food samples, the daily NP intake for an adult was determined to be 2.7 µg day−1, which is one-third of the value found in the 2002 study. However, our findings revealed that NPs remain ubiquitous in foods at relevant concentrations, which highlights the need for further examinations in particular the isomer-specific aspects. This is especially important as nonylphenol is found in human blood in many studies.

Selenium: widespread yet scarce, essential yet toxic

Selenium (Se) is an essential element for humans and animals, with one of the narrowest ranges between deficiency ( 400 µg day−1). Se is very widespread in all environments (rocks, soils, waters, air, plant and animal tissue) but in very low concentrations. Thus, there are no ores from which Se can be effectively mined. This can create a potential problem in supplying Se for commercial uses or for battling Se deficiency which already affects more than one billion people and is predicted to rise in the future. Besides Se deficiency, there are many incidents where excess Se in water and soil caused deformities in animals and humans. Often high-Se areas are found near past coal mining and burning sites, which have never been remediated and still pose a potential threat to human health. This article aims to inform readers about the general chemical characteristics of Se, environmental cycling of Se, and past incidents of Se deficiency and toxicity. The article also touches on the removal of excess Se from waters and soils, as well as biofortification methods for preventing Se deficiency in humans and animals.

Mesenchymal stromal cell treatment of donor kidneys during ex vivo normothermic machine perfusion: A porcine renal autotransplantation study.

Normothermic machine perfusion (NMP) of injured kidneys offers the opportunity for interventions to metabolically active organs prior to transplantation. Mesenchymal stromal cells (MSCs) can exert regenerative and anti-inflammatory effects in ischemia-reperfusion injury. The aims of this study were to evaluate the safety and feasibility of MSC treatment of kidneys during NMP using a porcine autotransplantation model, and examine potential MSC treatment-associated kidney improvements up to 14days posttransplant. After 75min of kidney warm ischemia, four experimental groups of n=7 underwent 14h of oxygenated hypothermic machine perfusion. In three groups this was followed by 240min of NMP with infusion of vehicle, 10million porcine, or 10million human adipose-derived MSCs. All kidneys were autotransplanted after contralateral nephrectomy. MSC treatment did not affect perfusion hemodynamics during NMP or cause adverse effects at reperfusion, with 100% animal survival. MSCs did not affect plasma creatinine, glomerular filtration rate, neutrophil gelatinase-associated lipocalin concentrations or kidney damage assessed by histology during the 14days, and MSCs retention was demonstrated in renal cortex. Infusing MSCs during ex vivo NMP of porcine kidneys was safe and feasible. Within the short posttransplant follow-up period, no beneficial effects of ex vivo MSC therapy could be demonstrated.

Iodine biofortification of sweet basil and lettuce grown in two hydroponic systems

Two hydroponic techniques (floating system and aeroponics) were assessed for iodine (I) biofortification of sweet basil (Ocimum basilicum L.) and baby-leaf lettuce (Lactuca sativa L.). Iodine was supplemented by adding KI into the nutrient solution to achieve a final I concentration of 10 μM. Shoot biomass production and leaf concentration of I, nitrates, total phenols and pigments were measured on the occasion of two successive cuts, 14 and 28 days after transplanting. In both the hydroponic systems, the supplementation of KI represented an effective method for the biofortification of basil as it did not affect the plant growth, while it moderately reduced the biomass production in lettuce. Leaf I accumulation occurred to a greater extent in aeroponics than the floating system in both species. In KI-treated basil plants, leaf I content ranged between 9.76 and 23.58 mg kg−1 FW. Consequently, 6 g of fresh basil leaves, which is contained in a portion of Italian pesto sauce (12 g), could satisfy 40%–94% of the Recommended Daily Intake (RDI) of iodine for healthy adults (150 μg day−1). In lettuce, leaf I contents of first-cut leaves were 1.55 and 3.60 mg kg−1 FW, in the floating system and aeroponics, respectively. Therefore, a serving size of 26 g of lettuce containing I from 1.55 (floating culture) to 3.60 (aeroponics) mg kg−1 FW could satisfy 27 % to 62 % of the RDI of iodine.Lettuce grew much less in the floating system than aeroponics, probably because of the lower dissolved oxygen level in the nutrient solution as compared to aeroponics. Basil was less sensitive to the oxygen availability in the root zone, since no differences were detected between the two hydroponic systems in terms of fresh and dry biomass.