Microplastics: Omnipresent and an ongoing challenge for medical science.

Micro- and nanoplastics are omnipresent not only in the environment, but have also been detected in human body fluids and tissue. The subsequent commentary provides a perspective about potential risks for human health as well as resulting challenges for medical science.

Determinants of exposure to acrylamide in European children and adults based on urinary biomarkers: results from the "European Human Biomonitoring Initiative" HBM4EU participating studies.

Little is known about exposure determinants of acrylamide (AA), a genotoxic food-processing contaminant, in Europe. We assessed determinants of AA exposure, measured by urinary mercapturic acids of AA (AAMA) and glycidamide (GAMA), its main metabolite, in 3157 children/adolescents and 1297 adults in the European Human Biomonitoring Initiative. Harmonized individual-level questionnaires data and quality assured measurements of AAMA and GAMA (urine collection: 2014-2021), the short-term validated biomarkers of AA exposure, were obtained from four studies (Italy, France, Germany, and Norway) in children/adolescents (age range: 3-18 years) and six studies (Portugal, Spain, France, Germany, Luxembourg, and Iceland) in adults (age range: 20-45 years). Multivariable-adjusted pooled quantile regressions were employed to assess median differences (ß coefficients) with 95% confidence intervals (95% CI) in AAMA and GAMA (µg/g creatinine) in relation to exposure determinants. Southern European studies had higher AAMA than Northern studies. In children/adolescents, we observed significant lower AA associated with high socioeconomic status (AAMA:ß = - 9.1 µg/g creatinine, 95% CI - 15.8, - 2.4; GAMA: ß = - 3.4 µg/g creatinine, 95% CI - 4.7, - 2.2), living in rural areas (AAMA:ß = - 4.7 µg/g creatinine, 95% CI - 8.6, - 0.8; GAMA:ß = - 1.1 µg/g creatinine, 95% CI - 1.9, - 0.4) and increasing age (AAMA:ß = - 1.9 µg/g creatinine, 95% CI - 2.4, - 1.4; GAMA:ß = - 0.7 µg/g creatinine, 95% CI - 0.8, - 0.6). In adults, higher AAMA was also associated with high consumption of fried potatoes whereas lower AAMA was associated with higher body-mass-index. Based on this large-scale study, several potential determinants of AA exposure were identified in children/adolescents and adults in European countries.

Trends of Exposure to Acrylamide as Measured by Urinary Biomarkers Levels within the HBM4EU Biomonitoring Aligned Studies (2000-2021).

Acrylamide, a substance potentially carcinogenic in humans, represents a very prevalent contaminant in food and is also contained in tobacco smoke. Occupational exposure to higher concentrations of acrylamide was shown to induce neurotoxicity in humans. To minimize related risks for public health, it is vital to obtain data on the actual level of exposure in differently affected segments of the population. To achieve this aim, acrylamide has been added to the list of substances of concern to be investigated in the HBM4EU project, a European initiative to obtain biomonitoring data for a number of pollutants highly relevant for public health. This report summarizes the results obtained for acrylamide, with a focus on time-trends and recent exposure levels, obtained by HBM4EU as well as by associated studies in a total of seven European countries. Mean biomarker levels were compared by sampling year and time-trends were analyzed using linear regression models and an adequate statistical test. An increasing trend of acrylamide biomarker concentrations was found in children for the years 2014-2017, while in adults an overall increase in exposure was found to be not significant for the time period of observation (2000-2021). For smokers, represented by two studies and sampling for, over a total three years, no clear tendency was observed. In conclusion, samples from European countries indicate that average acrylamide exposure still exceeds suggested benchmark levels and may be of specific concern in children. More research is required to confirm trends of declining values observed in most recent years.

Time Trends of Acrylamide Exposure in Europe: Combined Analysis of Published Reports and Current HBM4EU Studies.

More than 20 years ago, acrylamide was added to the list of potential carcinogens found in many common dietary products and tobacco smoke. Consequently, human biomonitoring studies investigating exposure to acrylamide in the form of adducts in blood and metabolites in urine have been performed to obtain data on the actual burden in different populations of the world and in Europe. Recognizing the related health risk, the European Commission responded with measures to curb the acrylamide content in food products. In 2017, a trans-European human biomonitoring project (HBM4EU) was started with the aim to investigate exposure to several chemicals, including acrylamide. Here we set out to provide a combined analysis of previous and current European acrylamide biomonitoring study results by harmonizing and integrating different data sources, including HBM4EU aligned studies, with the aim to resolve overall and current time trends of acrylamide exposure in Europe. Data from 10 European countries were included in the analysis, comprising more than 5500 individual samples (3214 children and teenagers, 2293 adults). We utilized linear models as well as a non-linear fit and breakpoint analysis to investigate trends in temporal acrylamide exposure as well as descriptive statistics and statistical tests to validate findings. Our results indicate an overall increase in acrylamide exposure between the years 2001 and 2017. Studies with samples collected after 2018 focusing on adults do not indicate increasing exposure but show declining values. Regional differences appear to affect absolute values, but not the overall time-trend of exposure. As benchmark levels for acrylamide content in food have been adopted in Europe in 2018, our results may imply the effects of these measures, but only indicated for adults, as corresponding data are still missing for children.

Anti-Inflammatory Effects of Melatonin in Rats with Induced Type 2 Diabetes Mellitus.

INTRODUCTION: Insulin resistance is associated with a pro-inflammatory state increasing the risk for complications in patients with type 2 diabetes mellitus (T2DM). In addition to its chronobiotic effects, the pineal hormone melatonin is known to exert anti-inflammatory and antioxidant effects. Melatonin was also suggested to affect insulin secretion. The aim of this study was therefore to investigate the effect of melatonin on inflammation in diabetic rats and to study the possible involvement of the melatonin receptor, MT2. MATERIALS AND METHODS: Male Sprague Dawley rats were randomly divided into four experimental groups (n = 10 per group): (1) control, (2) streptozotocin/nicotinamide induced diabetes type 2 (T2DM), (3) T2DM treated with melatonin (500 µg/kg/day), and (4) T2DM treated with melatonin (500 µg/kg/day for 6 weeks) and the selective MT2 receptor antagonist luzindole (0.25 g/kg/day for 6 weeks). Blood samples were taken for biochemical parameters and various tissue samples (liver, adipose tissue, brain) were removed for immunohistochemistry (IHC), Western blot (WB), and Q-PCR analyses, respectively. RESULTS: Melatonin significantly reduced increased blood levels of liver transaminases (AST, ALT), blood urea nitrogen (BUN), triglyceride, very low-density lipoprotein (VLDL), and cholesterol in diabetic rats with luzindole treatment partly reversing this effect regarding the lipids. Furthermore, the liver and adipose tissues of T2DM rats treated with melatonin showed lower expression of the inflammatory markers IL-1ß, IL-6, TNF-α, and NF-κB as compared to the T2DM group without melatonin. The results also showed that the MT2 receptor is at least partly involved in the protective effects of melatonin. CONCLUSIONS: Our results suggest that melatonin exerts relevant anti-inflammatory effects on various tissues in type 2 diabetic rats.

COVID-19: Regional Differences in Austria.

In the turbulent year 2020, overshadowed by the global COVID-19 pandemic, Austria experienced multiple waves of increased case incidence. While governmental measures to curb the numbers were based on current knowledge of infection risk factors, a retrospective analysis of incidence and lethality at the district level revealed correlations of relative infection risk with socioeconomic, geographical, and behavioral population parameters. We identified unexpected correlations between political orientation and smoking behavior and COVID-19 infection risk and/or mortality. For example, a decrease in daily smokers by 2.3 percentage points would be associated with an increase in cumulative incidence by 10% in the adjusted model, and an increase in voters of the right-wing populist party by 1.6 percentage points with an increase in cumulative mortality by 10%. While these parameters are apparently only single elements of complex causal chains that finally lead to individual susceptibility and vulnerability levels, our findings might have identified ecological parameters that can be utilized to develop fine-tuned communications and measures in upcoming challenges of this and other pandemics.

COVID-19 and air pollution in Vienna-a time series approach.

We performed a time series analysis in Vienna, Austria, investigating the temporal association between daily air pollution (nitrogen dioxide, NO2 and particulate matter smaller than 10 µm, PM10) concentration and risk of coronavirus disease 2019 (COVID-19) infection and death. Data covering about 2 months (March-April 2020) were retrieved from public databases. Infection risk was defined as the ratio between infected and infectious. In a separate sensitivity analysis different models were applied to estimate the number of infectious people per day. The impact of air pollution was assessed through a linear regression on the natural logarithm of infection risk. Risk of COVID-19 mortality was estimated by Poisson regression. Both pollutants were positively correlated with the risk of infection with the coefficient for NO2 being 0.032 and for PM10 0.014. That association was significant for the irritant gas (p = 0.012) but not for particles (p = 0.22). Pollutants did not affect COVID-19-related mortality. The study findings might have wider implications on an interaction between air pollution and infectious agents.

Correlative SEM-Raman microscopy to reveal nanoplastics in complex environments.

Nowadays "microplastics" (MPs) is an already well-known term and results of micro-sized particles found in consumer products or environments are regularly reported. However, studies of native MPs smaller than 1 µm, often referred to as nanoplastics (NPs), in analytically challenging environments are rare. In this study, a correlative approach between scanning electron microscopy and Raman microscopy is tested to meet the challenges of finding and identifying NPs in the 100 nm range in various environments, ranging from ideal (distilled water) to challenging (sea salt, human amniotic fluid). To test the viability of this approach in principle, standardized polystyrene beads (Ø 200 nm) are mixed into the various environments in different concentrations. Promising detection limits of 2 10-3 µg/L (distilled water), 20 µg/L (sea salt) and 200 µg/L (human amniotic fluid) are found. To test the approach in practices both sea salt and amniotic fluid are analysed for native NPs as well. Interestingly a nylon-NP was found in the amniotic fluid, maybe originating from the sampling device. However, the practical test reveals limitations, especially with regard to the reliable identification of unknown NPs by Raman microscopy, due to strong background signals from the environments. We conclude from this in combination with the excellent performance in distilled water that a combination of this approach with an advanced sample preparation technique would yield a powerful tool for the analysis of NPs in various environments.

Health Symptoms Related to Pesticide Use in Farmers and Laborers of Ecological and Conventional Banana Plantations in Ecuador.

Conventional banana farming is pesticide-intensive and leads to high exposure of farmworkers. Ecuador is the world's biggest exporter of bananas. In this field study in 5 communities in Ecuador, we recorded potentially pesticide-associated subjective health symptoms in farmworkers and compared pesticide users to workers in organic farming. With one exception, symptom rates were always higher in the pesticide-exposed group. Significance was reached in 8 out of 19 investigated symptoms with the highest odds ratios (and smallest p-values) for local irritation like skin and eye irritation (OR = 3.58, CI 1.10-11.71, and 4.10, CI 1.37-12.31, respectively) as well as systemic symptoms like dizziness (OR = 4.80, CI 1.55-14.87) and fatigue (OR = 4.96, CI 1.65-14.88). Moreover, gastrointestinal symptoms were reported more frequently by pesticide users: nausea (OR = 7.5, CI 1.77-31.77) and diarrhea (OR = 6.43, CI 1.06-30.00). The majority of farmworkers were not adequately protected from pesticide exposure. For example, only 3 of 31 farmworkers that had used pesticides recently reported using gloves and only 6 reported using masks during active spraying. Improved safety measures and a reduction in pesticide use are necessary to protect the health of banana farmworkers.

Air Pollution Is Associated with COVID-19 Incidence and Mortality in Vienna, Austria.

We determined the impact of air pollution on COVID-19-related mortality and reported-case incidence, analyzing the correlation of infection case numbers and outcomes with previous-year air pollution data from the populations of 23 Viennese districts. Time at risk started in a district when the first COVID-19 case was diagnosed. High exposure levels were defined as living in a district with an average (year 2019) concentration of nitrogen dioxide (NO2) and/or particulate matter (PM10) higher than the upper quartile (30 and 20 µg/m3, respectively) of all districts. The total population of the individual districts was followed until diagnosis of or death from COVID-19, or until 21 April 2020, whichever came first. Cox proportional hazard regression was performed after controlling for percentage of population aged 65 and more, percentage of foreigners and of persons with a university degree, unemployment rate, and population density. PM10 and NO2 were significantly and positively associated with the risk of a COVID-19 diagnosis (hazard ratio (HR) = 1.44 and 1.16, respectively). NO2 was also significantly associated with death from COVID-19 (HR = 1.72). Even within a single city, higher levels of air pollution are associated with an adverse impact on COVID-19 risk.

Perfluoroctanoic acid (PFOA) enhances NOTCH-signaling in an angiogenesis model of placental trophoblast cells.

Exposure to perfluoroalkyl substances (PFAS) was found to be associated with several pathological endpoints, including high cholesterol levels, specific defective functions of the immune system and reduced birth weight. While environmental PFAS have been recognized as threats for public health, surprisingly little is known about the underlying mechanisms of toxicity. We hypothesized that some of the observed vascular and developmental effects of environmental PFAS may share a common molecular pathway. At elevated levels of exposure to PFAS, a reduction in mean birth weight of newborns has been observed in combination with a high incidence rate of preeclampsia. As both, preeclampsia and reduced birth weight are consequences of an inadequate placental vascularization, we hypothesized that the adaptation of placental vasculature may get compromised by PFAS. We analyzed pseudo-vascular network formation and protein expression in the HTR8/SVneo cell line, an embryonic trophoblast cell type that is able to form vessel-like vascular networks in 3D-matrices, similar to endothelial cells. PFOA (perfluoroctanoic acid), but not PFOS (perfuoroctanesulfonic acid), induced morphological changes in the vascular 3D-network structure, without indications of compromised cellular viability. Incubation with PFOA reduced cellular sprouting and elongated isolated stalks in pseudo-vascular networks, while a γ-secretase inhibitor BMS-906024 induced directional opposite effects. We found a PFOA-induced increase in NOTCH intracellular domain (NICD) abundance in HTR8/SVneo, indicating that PFOA enhances NOTCH-signaling in this cell type. Enhancement of NOTCH-pathway by PFOA may be a key to understand the mode of action of PFAS, as this pathway is critically involved in many confirmed physiological/toxicological symptoms associated with PFAS exposure.

Nitrogen-Dioxide Remains a Valid Air Quality Indicator.

In epidemiological studies, both spatial and temporal variations in nitrogen dioxide (NO2) are a robust predictor of health risks. Compared to particulate matter, the experimental evidence for harmful effects at typical ambient concentrations is less extensive and not as clear for NO2. In the wake of the "Diesel emission scandal-Dieselgate", the scientific basis of current limit values for ambient NO2 concentrations was attacked by industry lobbyists. It was argued that associations between NO2 levels and medical endpoints were not causal, as NO2 in older studies served as a proxy for aggressive particulate matter from incineration processes. With the introduction of particle filters in diesel cars, NO2 would have lost its meaning as a health indicator. Austria has a high percentage of diesel-powered cars (56%). If, indeed, associations between NO2 concentrations and health risks in previous studies were only due to older engines without a particle filter, we should expect a reduction in effect estimates over time as an increasing number of diesel cars on the roads were outfitted with particle filters. In previous time series studies from Vienna over shorter time intervals, we have demonstrated distributed lag effects over days up to two weeks and previous day effects of NO2 on total mortality. In a simplified model, we now assess the effect estimates for moving 5-year periods from the beginning of NO2 monitoring in Vienna (1987) until the year 2018 of same and previous day NO2 on total daily mortality. Contrary to industry claims of a spurious, no longer valid indicator function of NO2, effect estimates remained fairly stable, indicating an increase in total mortality of previous day NO2 by 0.52% (95% CI: 0.35-0.7%) per 10 µg/m3 change in NO2 concentration.

Time Course of COVID-19 Cases in Austria.

COVID-19 is an infectious disease caused by a novel coronavirus, which first appeared in China in late 2019, and reached pandemic distribution in early 2020. The first major outbreak in Europe occurred in Northern Italy where it spread to neighboring countries, notably to Austria, where skiing resorts served as a main transmission hub. Soon, the Austrian government introduced strict measures to curb the spread of the virus. Using publicly available data, we assessed the efficiency of the governmental measures. We assumed an average incubation period of one week and an average duration of infectivity of 10 days. One week after the introduction of strict measures, the increase in daily new cases was reversed, and the reproduction number dropped. The crude estimates tended to overestimate the reproduction rate in the early phase. Publicly available data provide a first estimate about the effectiveness of public health measures. However, more data are needed for an unbiased assessment.

Daylight Saving Time Transitions: Impact on Total Mortality.

In Europe and many countries worldwide, a half-yearly changing time scheme has been adopted with the aim of optimizing the use of natural daylight during working hours and saving energy. Because the expected net economic benefit was not achieved, the discussion about the optimal solution has been reopened with a shifted focus on social and health related consequences. We set out to produce evidence for this discussion and analysed the impact of daylight saving time on total mortality of a general population in a time series study on daily total mortality for the years 1970-2018 in the city of Vienna, Austria. Daily deaths were modelled by Poisson regression controlling for seasonal and long-term trend, same-day and 14-day average temperature, humidity, and day of week. During the week after the spring transition a significant increase in daily total mortality of about 3% per day was observed. This was not the case during the week after the fall transition. The increase in daily mortality as observed in the week after spring DST-transition is most likely causally linked to the change in time scheme.

Indicators of Genotoxicity in Farmers and Laborers of Ecological and Conventional Banana Plantations in Ecuador.

Banana farming represents an important segment of agricultural production in Ecuador. The health of farmworkers might be compromised by the extensive use of pesticides in plantations applied under poorly regulated conditions. Due to an increased awareness of pesticide-related problems for nature, as well as for worker and consumer health, ecological farming has been established in some plantations of Ecuador. We set out to investigate the occupational health of workers in both conventional and ecological farming. Nuclear anomalies in buccal epithelial cells were used as short-term indicators for genotoxicity and a potentially increased cancer risk in the two groups of farmworkers. By application of the Buccal Micronucleus Cytome Assay (BMCA), we found the frequency of micronuclei in conventional pesticide using farmworkers significantly increased by 2.6-fold, and other nuclear anomalies significantly increased by 24% to 80% (except pyknosis with a non-significant increase of 11%) compared to the farmworkers on ecological plantations. These results demonstrate that ecological farming may provide an alternative to extensive pesticide use with significantly reduced indicators of cancer risk. In conventional farming, improvements in education and instruction regarding the safe handling of pesticides and protective equipment, as well as regulatory measures, are urgently needed.

More pesticides-less children?

A previously presented study investigated the impact of recent pesticide exposure on cytological signs of genotoxicity and on symptoms of intoxication in 71 male coffee workers in the Dominican Republic. An unexpected finding of this study was that conventional farming workers, among other symptoms, reported fewer children than controls working in organic farms without pesticide use. This study set out to investigate possible reasons for the latter difference. One statistical problem of this analysis is that the age of the workers is a strong predictor for the number of children and available data on the exposure determinants "duration of pesticide exposure" as well as "age at first pesticide exposure" are correlated with age. To correctly control statistics for these confounding parameters, different approaches to best control for age were explored. After careful elimination of the age-related confounding factors, a reduced number of children was still observed in exposed workers. The clearest effect is seen in those workers that reported first exposure before the age of 20 years. Socioeconomic factors could still confound that finding, but a direct effect of early life pesticide exposure is the most likely explanation of the observation.

Validity of reported indicators of pesticide exposure and relevance for cytotoxic and genotoxic effects on buccal cells.

Higher rates of nuclear anomalies in buccal cells of coffee workers exposed to pesticides in comparison to their unexposed peers were detected in our field study. Here, we extend our findings by examining other exposure indicators in this sample. Occupational exposure of 38 exposed and 33 non-exposed farmworkers was assessed as exposure days in the last month (0-25 days) and as years of exposure (0-47 years). Genotoxic and cytotoxic markers in buccal cells were analysed following standard procedures for buccal micronucleus cytome assay. Both exposure markers were associated with a higher frequency of nuclear anomalies with odds ratios more than 1. After restricting the analysis to the exposed workers only, this association remained only with the marker of recent exposure. In a secondary analysis also environmental exposure defined as proximity of the home to the nearest sprayed field (distance <1000 m) was assessed. Proximity led to increased rates (with odds ratios more than 3) of genotoxic but not cytotoxic nuclear anomalies. Reported recent frequency and intensity of pesticide use and application are a valid exposure marker relevant for cytological pathologies in the buccal mucosa. The exposure metric for environmental exposure was rather crude and confounding by some unmeasured factor cannot be fully excluded. Nevertheless, simple exposure indicators that can even be obtained under rather difficult field conditions do provide health-relevant and valid information.

Subjective Symptoms of Male Workers Linked to Occupational Pesticide Exposure on Coffee Plantations in the Jarabacoa Region, Dominican Republic.

Acute and sub-acute effects of pesticide use in coffee farmers have rarely been investigated. In the present field study, self-reported health symptoms from 38 male pesticide users were compared to those of 33 organic farmers. Results of cytological findings have been reported in an accompanying paper in this issue. The present second part of the study comprises a questionnaire based survey for various, potentially pesticide related symptoms among the coffee farmers. Symptom rates were generally higher in exposed workers, reaching significance in nine out of 19 assessed symptoms. Significantly increased symptom frequencies were related to neurotoxicity, parasympathic effects and acetylcholine esterase inhibition, with the highest differences found for excessive salivation, dizziness and stomach ache. We revealed a lack of precautionary measures in the majority of farmers. Better education, regulations, and safety equipment are urgently needed.