Average Concentration Research Articles

Mycotoxins in vegetating corn plants from experimental mono-sowing

The aim of present study was to reveal the mycotoxin contamination of vegetative maize (Zea mays L.) plants during the periods of leaf formation and panicle emergence. Early maturing hybrids of the varieties Krasnodarsky 194 MV, Ladozhsky 175 MV and Competence®, resistant to fungal diseases, were grown in the spring-summer period of 2023 on the experimental field of the Russian State Agrarian University – Moscow Agricultural Academy (Moscow) with sod-podzolic soil and the application of NPK fertilizers 16:16:16. For mycotoxicological analysis, aerial parts of plants were collected weekly from the phase of formation of the 3rd leaf (18 days after sowing. Samples of seedlings, leaves and stems (total number – 172), after drying, were ground in a laboratory mill and extracted with a mixture of acetonitrile and water in a volumetric ratio of 84:16 with a consumption of 10 ml per 1 g of sample. Mycotoxin content was determined in extracts after 10-fold dilution with phosphate-salt buffer solution pH 7.5 by indirect competitive enzyme immunoassay. T-2 toxin, deoxynivalenol, diacetoxiscirpenol, roridin A, sterigmatocystin and PR toxin were absent in the samples. Corn seedlings and leaves contained cyclopiazonic acid (CPA), emodin (EMO), mycophenolic acid (MPA), alternariol (AOL), ergot alkaloids (EA), aflatoxin B1 (AB1) and single samples – zearalenone (ZEN), ochratoxin A (OA) and citrinin (CIT) in concentrations from 16 up to 35 μg/kg. Fumonisins of group B are found only in early seedlings. The permanent contaminant of the stems was MPA, whereas EA and CIT were absent. In the seedlings and leaves of all hybrids, the detection of AOL and EA remained stable during the change of development phases, as did the average concentrations of CPA (about 100 μg/kg), AOL (from 17 to 27 μg/kg), EMO (35–58 μg/kg), MPA (28–41 μg/kg), EA (6–18 μg/kg) and AB1 (2 μg/kg). In the stems of plants in phases 7–9 of leaf and sweeping, variation in cases of detection of CPA, EMO, AOL, AB1 and OA was noted by varieties.

Carcinogenic and non-carcinogenic health risk assessment of heavy metals in the offal of animals from Felele Abattoir, Lokoja, Nigeria

The consumption of metal-contaminated offal of animals will affect the health of humans. Thus, the research determined the concentrations of heavy metals in the offal and muscle tissues of cows, goats, and ram slaughtered at the main abattoir in Lokoja, northcentral Nigeria. Furthermore, an evaluation was carried out to assess the potential health hazards faced by the indigenous population due to the consumption of heavy metals from these animals. The mean concentrations of metals (Al, Cd, Cr, Ni, and Pb) in the kidney, liver, and muscle of cows, goats, and rams were determined using Inductively Coupled Plasma Optical Emission Spectrometry. Estimated daily intake of the metals, hazard quotient, hazard index, and cancer risk were calculated. All internal organs had Ni levels above the regulatory threshold limit. The average concentration of Pb in the muscle tissue and liver of the tested animals exceeded the permissible limits by the WHO. Similarly, the concentration of Cd in the muscle tissues was above the Maximum Permissible Limit (MPL) of 0.05 mg kg−1. Except for cow kidneys, all internal organs contain Cr levels below the MPL (1.0) limit. The THQ value for the metals was < 1 except Cd. It indicates potential health risks due to Cd. The calculated HI values were > 1. The percentage contribution of Cd to the HI value was the highest. The observed sequence is Cd > Ni > Cr > Pb > Al. The results show that eating the offal and muscle under investigation has a carcinogenic effect.

Heavy metal contamination and human health risk assessment in the soils grown field crops in Antalya, Türkiye

ABSTRACT Soil pollution results from heavy metals has become a severe environmental concern. Heavy metals pose a risk to human health by entering the food chain. The aim of this study was to determine the concentrations, sources and potential ecological and human health risks of heavy metals in soils which grown field crops in Antalya, Turkey. Soil samples were collected at depths of 0–30 cm from 292 fields and concentrations of cadmium (Cd), lead (Pb), nickel (Ni), chromium (Cr), cobalt (Co), iron (Fe), manganese (Mn), copper (Cu) and zinc (Zn) were determined. The mean concentrations of total Cd, Pb, Ni, Cr, Co, Fe, Mn, Cu and Zn were 4.73, 68.67, 152.74, 98.52, 24.77, 28098, 823, 42.72 and 62.85 mg kg−1, respectively. These results showed that the average concentrations of Cd, Pb, Ni, Cr, Co, Cu and Mn exceeded the Upper continental crust average. Enrichment factor (EF), geo-accumulation index (I geo) and contamination factor (CF) values of soils indicate serious enrichment for Cd. Principal component analyses (PCA) indicated that Co, Cr and Ni was lithogenic origins, but Fe and Pb concentrations were determined by lithological and anthropogenic sources. Hazard index (HI) values of heavy metals were < 1, suggesting that non-carcinogenic health risks to adult residents. In addition, the total carcinogenic risk (TCR) values except for Cr, suggesting that carcinogenic risks for residents were not expected. The results showed that children were more sensitive to the non-carcinogenic and carcinogenic effects of heavy metals.

Anthropogenic impacts on polycyclic aromatic hydrocarbons in surface water: Evidence from the COVID-19 lockdown

The lockdown restrictions against coronavirus disease 2019 (COVID-19) have led to unprecedented reductions in global anthropogenic activities. Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic combustion-induced pollutants, but the influence of anthropogenic responses to COVID-19 on PAH contamination remains largely unknown. Here we quantified the impacts of lockdown restrictions on 16PAH pollution based on the data in concentrations dissolved in the water phase and absorbed on the suspended particulate matter (SPM) in the Elbe River from 2015 to 2021 and determined the changes in source contributions classified by individual years and stations. Results show that the annual average PAH concentrations in water and SPM were determined as 0.055 μg·L-1 and 3.77 mg·kg-1 from 2015 to 2021, respectively. Pronounced declines in PAH on SPM (up to -18 %) were observed during the three lockdowns in Germany from 2020 to 2021. However, dramatic rebounds of anthropogenic activities during the removal of the lockdown led to increases (up to 29 %) in ∑16PAH concentrations compared to the same period in previous years. Through the source apportionment method, vehicle and coal emissions were the two most predominant sources of PAHs in the river. Vehicle contribution decreased during the lockdown, while coal emissions increased by 5 %. Health risks for three age groups were assessed as potential low risk and decreased by 18 % from 1.54 × 10–4 in 2015 to 1.27 × 10–4 in 2019, and rebounded to 1.40 × 10–4 in 2020–2021. The findings of this study highlight the strong consistency between PAH concentrations and anthropogenic intensity, implying that source control from improved cleaner production is an effective pathway for mitigating PAH contamination in the aquatic environment.

Airborne Pollen Seasonality of Kars Province, a high-altitude region in NE Anatolia-Türkiye

Aeropalynological studies quantify pollen taxa present in the atmosphere and elucidate their seasonal variations and regional distribution, which is vital for the precise diagnosis and management of sensitive individuals. Utilizing a Hirst-type volumetric 7-day pollen and spore trap during 2012 and 2013, this study conducted an aerobiological investigation in Kars province, Türkiye, a region characterized by high altitude and severe climate. Across the two-year study period, an average annual pollen concentration of 14,931 pollen/m3 was recorded with 39 taxa identified, with 29.31% woody, 70.58% herbaceous, and 0.11% unidentified. The peak pollen concentrations were recorded in June. The seven most dominant taxa were Poaceae, Pinaceae, Artemisia, Amaranthaceae, Urticaceae, Quercus, Cupressaceae/Taxaceae. The data indicated a significant risk period for individuals with pollen allergies from June to July. Statistical analyses were performed to investigate the correlation between the daily pollen concentrations of the dominant pollen types and the variables. The results demonstrated that an increase in temperature was positively correlated with higher pollen counts, whereas increased average relative humidity was associated with reduced pollen concentrations. Notably, herbaceous pollen taxa were more prevalent in Kars, which contrasts with the results of studies conducted in other regions. Additionally, the main pollen season starts approximately six weeks later than that in lower altitudes areas, which is likely attributable to distinctive regional ecological factors. These findings underscore the importance of localized aerobiological monitoring for effective public health responses to pollen allergies.

Changes in the Direct Climate Effect of Black Carbon Aerosols in East Asia Under the “Dual Carbon” Goal of China

AbstractIn the context of China's “dual carbon” goal, emissions of air pollutants are expected to significantly decrease in the future. Thus, the direct climate effects of black carbon (BC) aerosols in East Asia are investigated under this goal using an updated regional climate and chemistry model. The simulated annual average BC concentration over East Asia is approximately 1.29 μg/m3 in the last decade. Compared to those in 2010–2020, both the BC column burden and instantaneous direct radiative forcing in East Asia decrease by more than 55% and 80%, respectively, in the carbon peak year (2030s) and the carbon neutrality year (2060s). Conversely, the BC effective radiative forcing (ERF) and regional climate responses to BC exhibit substantial nonlinearity to emission reduction, possibly resulting from different adjustments of thermal‐dynamic fields and clouds from BC‐radiation interactions. The regional mean BC ERF at the tropopause over East Asia is approximately +1.11 W/m2 in 2010–2020 while negative in the 2060s. BC‐radiation interactions in the present‐day impose a significant annual mean cooling of −0.2 to −0.5 K in central China but warming +0.3 K in the Tibetan Plateau. As China's BC emissions decline, surface temperature responses show a mixed picture compared to 2010–2020, with more cooling in eastern China and Tibet of −0.2 to −0.3 K in the 2030s, but more warming in central China of approximately +0.3 K by the 2060s. The Indian BC might play a more important role in East Asian climate with reduction of BC emissions in China.

Prenatal exposure to non-persistent chemicals and fetal-to-childhood growth trajectories.

Prenatal exposure to non-persistent chemicals, including organophosphate pesticides, phthalates, and bisphenols, is associated with altered fetal and childhood growth. Few studies have examined these associations using longitudinal growth trajectories or considering exposure to chemical mixtures. Among 777 participants from the Generation R Study, we used growth mixture models to identify weight and body mass index (BMI) trajectories using weight and height measures collected from the prenatal period to age 13. We measured exposure biomarkers for organophosphate pesticides, phthalates, and bisphenols in maternal urine at three timepoints during pregnancy. Multinomial logistic regression was used to estimate associations between averaged exposure biomarker concentrations and growth trajectories. We used quantile g-computation to estimate joint associations with growth trajectories. Phthalic acid (OR: 1.4, 95% CI: 1.01, 1.9) and bisphenol A (BPA; OR: 1.5, 95% CI: 1.0, 2.2) were associated with higher odds of a growth trajectory characterized by smaller prenatal and larger childhood weight relative to a referent trajectory of larger prenatal and average childhood weight. Biomarkers of organophosphate pesticides, individually and jointly, were associated with lower odds of a growth trajectory characterized by average prenatal and lower childhood weight. Exposure to phthalates and BPA was positively associated with a weight trajectory characterized by lower prenatal and higher childhood weight, while exposure to organophosphate pesticides was negatively associated with a trajectory of average prenatal and lower childhood weight. This study is consistent with the hypothesis that non-persistent chemical exposures disrupt growth trajectories from the prenatal period through childhood.

Spatiotemporal distribution, risk levels, and transport variations in neonicotinoids and fipronil and its metabolites cross a river-to-sea continuum

Neonicotinoids (NEOs) and fipronil are widely used in pest control, but their spatiotemporal distribution and risk levels in the “river–estuary–bay” system remain unclear. Between 2018 and 2021, 148 water samples from rivers to inshore and offshore seawater in Laizhou Bay, China were collected to investigate the presence of eight NEOs and fipronil and its metabolites (FIPs). Significant seasonal variations in NEOs were observed under the influence of different cultivation practices and climatic conditions, with higher levels in the summer than in the spring. The average concentrations of total neonicotinoids (ΣNEOs) and ∑FIPs decreased from rivers (63.64 ng/L, 2.41 ng/L) to inshore (22.62 ng/L, 0.14 ng/L) and offshore (4.48 ng/L, 0.10 ng/L) seawater of Laizhou Bay. The average concentrations of ΣNEOs decreased by 85.3 % from 2018 to 2021. The predominant insecticides in the study area were acetamiprid, thiamethoxam, imidacloprid, and fipronil sulfone, with a gradual shift toward low-toxicity and environmentally friendly species over time. Influenced by agricultural intensity, ∑NEOs were mostly distributed in the Yellow River, Xiaoqing River, and their estuaries, where they pose chronic ecological risks. However, FIP exhibited high risk in certain rivers and sewage treatment plants owing to the use of animal repellents or landscape gardening insecticides. This study provides evidence of the transfer of NEOs and FIPs from rivers to the ocean and also clarifies their transition dynamics and changes in risk levels from rivers to oceans. Additionally, the study offers data support for identifying critical pesticide control areas.

Polystyrene microplastics facilitate renal fibrosis through accelerating tubular epithelial cell senescence

Microplastics (MPs), emerging contaminants, are easily transported and enriched in the kidney, suggesting the kidney is susceptible to the toxicity of MPs. In this study, we explored the toxicity of MPs, including unmodified polystyrene (PS), negative-charged PS-SO3H, and positive-charged PS-NH2 MPs, in mice models for 28 days at a human equivalent concentration. The results showed MPs significantly increased levels of UREA, urea nitrogen (BUN), creatinine (CREA), and uric acid (UA) levels in serum and white blood cells, protein, and microalbumin in urine. In the kidney, MPs triggered persistent inflammation and renal fibrosis, which was caused by the increased senescence of tubular epithelial cells. Moreover, we identified the critical role of the Klotho/Wnt/β-catenin signaling pathway in the process of MPs induced senescence of tubular epithelial cells, promoting the epithelial-mesenchymal transformation of epithelial cells. MPs supported the secretion of TGF-β1 by senescent epithelial cells and induced the activation of renal fibroblasts. On the contrary, restoring the function of Klotho can alleviate the senescence of epithelial cells and reverse the activation of fibroblasts. Thus, our study revealed new evidence between MPs and renal fibrosis, and adds an important piece to the whole picture of the plastic pollution on people's health.

Long-term Exposure to Ambient Air Pollution and its Association with Mental Well-Being, Depression and Anxiety: A Nationally Representative Study.

Exposure to ambient air pollution may play a role in the onset of common mental disorders like depressive and anxiety disorders. The association of long-term exposure to particles smaller than 10 μm (PM10) with these diseases remains unclear. This study aimed to estimate the association of long-term exposure to PM10 with mental well-being and the frequency of probable diagnosis of common mental disorders. A nationally representative cross-sectional study was done in mainland Portugal. Long-term exposure was estimated through one-year average concentrations of PM10, calculated with data from the Portuguese Environment Agency, attributed individually considering individuals' postal codes of residence. The mental well-being and the probable diagnosis of common mental disorders were ascertained through the five-item Mental Health Inventory scale. Linear and Robust Poisson regression models were computed to estimate change percentages, prevalence ratios (PR), and their 95% confidence intervals (95% CI). The median (interquartile range) concentration of PM10 was 18.6 (15.3 - 19.3) μg/m3. The mental well-being score was 72 (56 - 84) points, on a scale from 0 to 100. A probable diagnosis of common mental disorders was found in 22.7% (95% CI: 20.0 to 25.6). Long-term exposure to PM10 was associated with a non-statistically significant decrease in the mental well-being score [for each 10 μg/m³ increment in one-year average PM10 concentrations, there was a 2% (95% CI: -8 to 4) decrease], and with a non-statistically significant increase in the common mental health frequency (PR = 1.012, 95% CI: 0.979 to 1.045). We did not find statistically significant associations between long-term exposure to PM10 and mental well-being or the frequency of probable diagnosis of common mental disorders. These results may be explained by the reduced variability in the exposure values, given the geographical distribution and functioning of the network of air quality monitoring stations. This study contributes with evidence for low levels of air pollutants, being one of the first to adjust for individual and aggregate-level variables. Moreover, to the best of our knowledge, this was the first nationally representative, population-based study conducted on the Portuguese population using real-life data. Maintaining a robust and nationwide air quality monitoring network is essential for obtaining quality exposure data.

Highly Efficient Quenching of Singlet Oxygen by DNA Origami Nanostructures.

DNA origami nanostructures (DONs) are able to scavenge reactive oxygen species (ROS) and their scavenging efficiency toward ROS radicals was shown to be comparable to that of genomic DNA. Herein, we demonstrate that DONs are highly efficient singlet oxygen quenchers outperforming double-stranded (ds) DNA by several orders of magnitude. To this end, a ROS mixture rich in singlet oxygen is generated by light irradiation of the photosensitizer methylene blue and its cytotoxic effect on Escherichia coli cells is quantified in the presence and absence of DONs. DONs are found to be vastly superior to dsDNA in protecting the bacteria from ROS-induced damage and even surpass established ROS scavengers. At a concentration of 15 nM, DONs are about 50 000 times more efficient ROS scavengers than dsDNA at an equivalent concentration. This is attributed to the dominant role of singlet oxygen, which has a long diffusion length and reacts specifically with guanine. The dense packing of the available guanines into the small volume of the DON increases the overall quenching probability compared to a linear dsDNA with the same number of base pairs. DONs thus have great potential to alleviate oxidative stress caused by singlet oxygen in diverse therapeutic settings.

Multi-Year Continuous Observations of Ambient PM2.5 at Six Sites in Akure, Southwestern Nigeria

The spatial–temporal variations of fine particulate matter (PM2.5) in Akure, a city in southwestern Nigeria, are examined based on multi-year continuous observations using low-cost PM2.5 sensors at six different sites. The average annual concentration of PM2.5 across these sites was measured at 41.0 µg/m3, which surpassed both the Nigerian national air quality standard and the World Health Organization air quality guideline level. PM2.5 levels were significantly higher during the dry season (November–March), often exceeding hazardous levels (over 350 µg/m3), than during the wet season. The analyses of trends in air mass trajectories and satellite data on fire occurrences imply that the transport of dust and accumulation of PM2.5 originating from local/regional open burning activities played crucial roles in increased PM2.5 concentrations during the dry season. Further, site-to-site variations in the PM2.5 levels were observed, with relatively high concentrations at less urbanized sites, likely due to high local emissions from solid fuel combustion, waste burning, and unpaved road dust. Diurnal patterns showed morning and evening peaks at less urbanized sites, accounting for an estimated 51–77% of local emissions. These results highlight the importance of local emission sources in driving spatial–temporal PM2.5 variations within the city and the need for targeted mitigation strategies to address the significant air pollution challenges in Akure and similar regional cities in West Africa.

Assessing the significance of leaf chlorophyll content for measuring the vegetation health in mangrove species along the Kerala Coast, India – A multi-proxy approach

This study aimed to estimate the chlorophyll content of mangrove species distributed along the Kerala coast of India, and also to address the critical issue of assessing the health of these ecosystems. We identified 16 mangrove species and estimated their chlorophyll concentration levels through a combination of field reconnaissance, in situ radiometric measurements at 218 locations, and UV spectrophotometric (ultraviolet–visible) analysis in the laboratory, and estimated the vegetation health from spectral indices using IRS (Indian Remote Sensing) Resourcesat LISS-IV (Linear Imaging and Self-Scanning Sensor) satellite imagery. This study revealed that the dominant species in Kerala are Avicennia officinalis, A. marina, Rhizophora mucronata and Excoecaria agallocha, whereas, Bruguiera sexangula is sparsely spread. Approximately 14 % of the mangrove cover along the Kerala coast is under stress due to various factors, including climate change and anthropogenic influences. Significantly, two of the 16 species, Avicennia marina and Rhizophora appiculata appeared relatively healthy, with average chlorophyll concentration index (CCI) values of 311.89±40.13 µmol/m2 and 553.42±23.24 µmol/m2, respectively. However, other dominant species Avicennia officinalis, Rhizophora mucronata, and Excoecaria agallocha exhibited average CCI values of 582.35±147.61, 611.7±104.58, and 559.04±141.13 respectively, and seemed to be under stress, calling for serious conservation measures. Our study also revealed the potential of cost-effective IRS LISS-IV imagery for identifying mangrove species and for estimating the chlorophyll concentration and plant vigour together with field and laboratory observations and measurements.

Population Pharmacokinetic Modeling and Exposure-Response Analysis for the Antibody-Drug Conjugate Enfortumab Vedotin in Locally Advanced or Metastatic Urothelial Carcinoma.

Enfortumab vedotin is a fully human monoclonal antibody directed to Nectin-4 and conjugated to monomethyl auristatin E (MMAE), approved for treatment of previously treated locally advanced or metastatic urothelial carcinoma (mUC). This population analysis characterized pharmacokinetics of enfortumab vedotin and free (unconjugated) MMAE, identified covariates affecting pharmacokinetics, and evaluated weight-based dosing for enfortumab vedotin. Exposure-response analyses characterized relationships between enfortumab vedotin and free MMAE exposures and efficacy/safety endpoints. Data from 748 patients with locally advanced or mUC in 5 clinical studies were analyzed using nonlinear mixed-effects modeling. Patients received enfortumab vedotin 0.50-1.25 mg/kg every 3 weeks or on days 1, 8, and 15 of a 28-day cycle. Relevant covariates retained in final models were evaluated for clinical relevance to enfortumab vedotin and free MMAE exposures. Although some covariates produced differences in exposure, the magnitude of changes was not clinically meaningful. Simulations indicated weight-based dosing yielded more consistent exposures across body weight groups vs. a hypothetical fixed-dose regimen of enfortumab vedotin 95 mg (calculated for median body weight, 75 kg). Exposure-response analysis showed average enfortumab vedotin concentrations were not a statistically significant predictor of overall survival (hazard ratio 0.91, 95% confidence interval: 0.72-1.14; P = 0.41); all exposure quartiles had a greater median overall survival than chemotherapy (11.0-12.6 vs. 9.0 months). Enfortumab vedotin and free MMAE exposures were statistically significant predictors of grade ≥ 3 treatment-related adverse events (both P < 0.0001). This analysis supports enfortumab vedotin 1.25 mg/kg on days 1, 8, and 15 of a 28-day cycle.

Preparation of slow-release carbon source fillers from agricultural solid waste for efficient nitrogen removal from municipal wastewater: Removal performance, microbial community and mechanisms

In this study, five types of agricultural wastes, were used as alternative materials for slow-release carbon source, alternative materials were prepared as slow-release carbon source fillers (ZCF) using a no-sintering method, and studied by leaching elements, carbon release, nitrification and denitrification potential, and bio-attachment performance, walnut shell-based filler was found to have better performance in terms of persistence of carbon release, impact stability, carbon biochemistry and green safety. When HRT was 8 h in H-O, 12 h in H-A, and R was 100 % and C/N was 2 in H-Z BAF, the average concentrations of effluent NH4+-N and TN were only 0.4 and 12.2 mg/L, which achieved the high efficiency and economy of H-Z BAF under low C/N conditions. The newly prepared ZCF had a rougher outer surface, a uniformly distributed flocculent structure and numerous microporous channels on the inner surface, and the carbon source inside the filler was degraded or transformed by microorganisms, as compared to the filler in H-O and H-A at the later stage of use. The abundance of nitrifying bacteria, denitrifying bacteria was increased in the H-Z BAF, and that functional CAZymes were enriched and involved in the degradation of cellulose and hemicellulose, can be efficiently utilized by microorganisms. This study provides technical support for the development of cheap, stable and efficient slow-release carbon sources and their application in denitrification of municipal wastewater plant tailwater.

Environmental and energy efficiency of a selected municipal wastewater treatment plant – a case study

Based on the analysis of environmental and energy efficiency in the years 2019–2021 in the selected sewage treatment plant (WWT) located in the southern Poland with mechanical-biological wastewater treatment, it was found that the highest level of pollution reduction of 98% enabled the highest BOD5 concentration to be reduced more than 800 times. The operation of the sewage treatment plant was characterized by variable efficiency of the treatment process, which was demonstrated by significant differences in chemical indicators (BOD5, COD, P, TSS and N). Low average concentration of total nitrogen below 4 mg l−1 occurred with a reduction of pollutants at a level not exceeding 90%. Noticeable energy consumption of 1.58 kWh m−3 related to the increase in the amount of treated sewage, confirmed by a moderate correlation, indicated the need to optimize the treatment process.

Agronomic Effectiveness of Zinc Sources as Micronutrient Fertilizers: A Comprehensive Review’

Zinc naturally occurs in the earth's crust as part of rocks and ore minerals. The average concentration of zinc in the lithosphere is 80 mg kg-1. While zinc is relatively immobile in soil, it is moderately mobile in plants. As a vital micronutrient for both humans and animals, zinc plays an essential role in plants as a catalytic, structural and regulatory cofactor for many enzyme reactions. It is necessary for the metabolism of carbohydrates, protein synthesis, the biosynthesis of growth hormones (particularly indoleacetic acid) and the maintenance of cell membrane integrity. Zinc deficiency is a widespread problem affecting both plants and humans in many regions of the world. To address this issue and improve plant zinc nutrition and yields, both soil and foliar zinc fertilizers have been applied. The agronomic effectiveness of Zn fertilizers has been related to the management factors such as placement, source type, seed treatment, foliar spray and biofortification that can affect the effectiveness of Zn fertilizers.

Implications of ocean warming and acidification on heavy metals in surface seawater of the Bohai Sea

At present, a clear dependency of the dynamics upon temperature and pH has not been established for many heavy metals (HMs), so making it difficult to project and quantify the impact of ocean warming and acidification on metal biogeochemistry in future scenarios. To understand the responses of HMs to future ocean warming and acidification, we estimated the spatial-temporal variations and pollution status of six dissolved HMs (i.e., Cu, Zn, Pb, Cd, Hg, and As) in surface seawater throughout the Bohai Sea during 2012–2014. The results showed that the average concentrations of Cu, Zn, Pb, Cd, Hg, and As in seawater of the Bohai Sea were between 2.01–3.18, 10.47–15.58, 0.85–2.31, 0.25–0.55, 0.05–0.13, and 1.24–1.98 μg L-1, respectively. Spatially, the average concentrations of the studied HMs generally decreased from the three bays towards the central area, except for Hg which was relatively high in the central Bohai Sea in some cases. This implied that, in addition to continental inputs, there may be other processes affecting the distribution pattern of Hg, such as cyclonic or anticyclonic gyres, benthic fluxes between surface and bottom layers, and some marine planktonic and microbial activities. The pollution assessments of six HMs in seawater revealed that the major risk pollutants were Pb and Hg across the Bohai Sea. Analyses of the local and interactive effects of temperature and pH on HMs showed that the interactive effect of changing temperature and pH on HMs is much more complex than a direct temperature/pH relationship with HMs. Altogether, the results suggested that future ocean warming and acidification will significantly influence the concentrations of dissolved HMs in seawater of the Bohai Sea, but with different relationships.

Oligosaccharide Profile of Milk from 60 Mothers Breastfeeding of Infants Aged 45 Days in Abidjan, Ivory Coast

Introduction: Breast milk contains essential macro and micronutrients for infant maturation. Among these macronutrients are oligosaccharides, considered prebiotics. They are the third most abundant component of breast milk after lipids and lactose, and their concentrations are influenced by various factors, including maternal dietary habits. This study aims to evaluate the effect of two dietary habits on the variation of the oligosaccharide profile in breast milk. Methods: The study involved 60 mothers of full-term, exclusively breastfed infants. Five (5) ml milk samples were collected from mothers of 45-day-old infants, and a questionnaire on the frequency of consumption of staple foods and fruits was administered. The correlation between the concentrations of N-acetylneuraminic acid (Neu5Ac) and 2’-fucosyllactose (2’-FSL) and the dietary habits of breastfeeding mothers was analyzed using SPSS statistical software. Results: The average concentrations of Neu5Ac and 2’-FSL in mature breast milk were 2.20 ± 0.83 and 1.19 ± 0.56 g/L for mothers consuming rice with peanut sauce (R-PS) and 2.45 ± 0.65 and 1.76 ± 0.66 g/L for those consuming attiéké with fried fish (A-FF). Statistical analyses revealed no significant difference (P &gt; 0.05) in oligosaccharide content between the milk of mothers who consumed R-PS and A-FF. However, there was a positive correlation between the frequency of fruit consumption and the occurrence of gastroenteritis in infants (r = 0.504) and a significant decrease in the 2’-fucosyllactose content in the milk of A-FF mothers who consumed oranges 3 to 5 times a week (P &lt; 0.05). Conclusion: The consumption of R-PS and A-FF, along with moderate fruit consumption, positively influences the oligosaccharide profile of breast milk. Particular attention should be given to nutritional education during lactation due to its potential impact on infant health through microbiota development.

Epigallocatechin-3-gallate adsorbed on core–shell gold nanorod@mesoporous silica nanoparticles, an antioxidant nanomaterial with photothermal properties

Epigallocatechin-3-gallate (EGCG) exhibits several pharmacological activities with potential benefits for human health, however, it has low oral bioavailability. A promising approach is to transport EGCG in a nanostructured system to protect it until it reaches the site of action and also allow combining chemotherapy with phototherapy to improve its therapeutic efficiency. The aim of this work was to synthesize GNR@mSiO2-NH2/EGCG and characterize the adsorption process, its antioxidant activity, properties and photothermal stability, for its potential use in chemo-photothermal therapy. The nanosystem presented good encapsulation efficiency (19.2 %) and EGCG loading capacity (6.0 %). The DPPH• free radical scavenging capacity (RSA) and chelating activity of the nanosystem was 60.7 ± 6.9 % and 71.0 ± 6.4 % at an EGCG equivalent concentration of 1 µg/mL and 30 µg/mL, respectively. The core–shell NPs presented a good photothermal transduction efficiency of 17 %. EGCG free, as well as its RSA and chelating activity, remained stable after NIR irradiation (808 nm, 7 W/cm2). The morphology of GNR@mSiO2 remained intact after being irradiated with NIR, however, ultrasmall gold NPs could be observed, probably a product of photocracking of GNR. In summary, the nanosystem has good antioxidant activity, photothermal stability, and photothermal transduction ability making it potentially useful for chemo-photothermal therapy.