Micro- and nanoplastics - current state of knowledge with the focus on oral uptake and toxicity.

The production and use of plastics has constantly increased over the last 30 years. Over one third of the plastics is used in disposables, which are discarded within three years of their production. Despite efforts towards recycling, a substantial volume of debris has accumulated in the environment and is slowly degraded to micro- and nanoplastics by weathering and aging. It has recently been discovered that these small particles can enter the food chain, as for example demonstrated by the detection of microplastic particles in honey, beer, salt, sea food and recently in mineral water. Human exposure has further been documented by the detection of plastic microparticles in human feces. Potential toxic consequences of oral exposure to small plastic particles are discussed. Due to lacking data concerning exposure, biodistribution and related effects, the risk assessment of micro- and nanoplastics is still not possible. This review focuses on the oral uptake of plastic and polymer micro- and nanoparticles. Oral exposure, particle fate, changes of particle properties during ingestion and gastrointestinal digestion, and uptake and transport at the intestinal epithelium are reviewed in detail. Moreover, the interaction with intestinal and liver cells and possibly resulting toxicity are highlighted.

Uptake and effects of orally ingested polystyrene microplastic particles in vitro and in vivo.

Evidence exists that humans are exposed to plastic microparticles via diet. Data on intestinal particle uptake and health-related effects resulting from microplastic exposure are scarce. Aim of the study was to analyze the uptake and effects of microplastic particles in human in vitro systems and in rodents in vivo. The gastrointestinal uptake of microplastics was studied in vitro using the human intestinal epithelial cell line Caco-2 and thereof-derived co-cultures mimicking intestinal M-cells and goblet cells. Different sizes of spherical fluorescent polystyrene (PS) particles (1, 4 and 10 µm) were used to study particle uptake and transport. A 28-days in vivo feeding study was conducted to analyze transport at the intestinal epithelium and oxidative stress response as a potential consequence of microplastic exposure. Male reporter gene mice were treated three times per week by oral gavage with a mixture of 1 µm (4.55 × 107 particles), 4 µm (4.55 × 107 particles) and 10 µm (1.49 × 106 particles) microplastics at a volume of 10 mL/kg/bw. Effects of particles on macrophage polarization were investigated using the human cell line THP-1 to detect a possible impact on intestinal immune cells. Altogether, the results of the study demonstrate the cellular uptake of a minor fraction of particles. In vivo data show the absence of histologically detectable lesions and inflammatory responses. The particles did not interfere with the differentiation and activation of the human macrophage model. The present results suggest that oral exposure to PS microplastic particles under the chosen experimental conditions does not pose relevant acute health risks to mammals.

Seasonal variation of body weight loss after bariatric surgery.

Seasonal variations have been described in humans in several variables such as sleep, mood, appetite, food preferences, or body weight. We hypothesized that these variations could also influence the decrease in body weight rate in patients submitted to body weight loss interventions. Thus, here we tested the variations of weight loss according to the time of the year the surgery took place in a group patients (n = 1322) submitted to bariatric surgery in the Hospital Universitari de la Vall d'Hebron in Barcelona (geographical coordinates: 41°25'41″N 2°8'32″E). For the analysis, the percentage of total body weight loss (%TWL), excess body weight loss (%EWL) and percentage of body mass index loss (%BMIL) were calculated at 3 (n = 1255), 6 (n = 1172), 9 (n = 1002), and 12 months (n = 1076) after surgery. For %EWL and %BMIL a statistically significant seasonal variation was detected when the variables were calculated at 3 months, but not at the other times, with more weight loss in summer-fall. However, seasonal variations were not detected for %TWL (p = 0.09). The mean amplitude of the seasonal rhythm for %EWL was of 1.8%, while for the rhythm of %BMIL was 0.7%. Moreover, a second peak was detected in January-February modulating the seasonal rhythm of the two variables. Results confirm seasonal variations in humans and indicate that short term responses to weight loss can be modulated by the time of year.

Seasonal variations of changes in lipid and glucidic variables after bariatric surgery.

Seasonality is a phenomenon that is characterized by changes over the year in sleep, mood, behaviour, appetite and body weight. In humans, seasonal variations have been found in certain variables, such as lipid variables and body mass index. We hypothesize that this rhythm could influence the expected variation of the levels of biochemical variables in cases of body weight loss. Thus, the goal of this study was to observe whether the time of year in which bariatric surgery (BS) took place modulated the changes in several variables related to glucidic and lipid metabolism. Blood samples were obtained from 24 women and 10 men before BS and 1 and 3 months after BS. We calculated the percentage of variation that occurred for each individual and for each variable as a function of the time of the year. Data were adjusted to a 12-month period sinusoidal curve, with significance being set at p < 0.05. The results showed that almost all of the studied variables changed due to the BS according to a seasonal rhythm. Most of the variables showed a decrease that was most prominent in winter. In the cases of body mass index (BMI), adrenocorticotropin hormone (ACTH), and cortisol, the highest variation occurred in winter. Insulin and cholesterol in high-density lipoproteins (cHLD) variations were higher in springtime. Glucose variation showed a decrease after surgery with acrophase in summer-fall and plasminogen activator inhibitor-1 (PAI-1) and homeostatic model assessment-insulin resistance (HOMA-IR) in spring-summer. Ghrelin levels showed increases with a rhythm of variation with an acrophase in summer-fall. The seasonal rhythm found in this study fits nearly with the inverse of the endogenous circannual rhythm of the variables studied. The time of the year when the highest variation takes place is related to the circannual rhythm of the variable. The results agree with the manifestation of seasonal rhythm in human biochemical variables, which are reflected in the responses to weight loss after BS.

El BOAR, un cuestionario de indicadores salutogénicos para población trabajadora / BOAR, a questionnaire of salutogenic indicators for working population

Antecedentes: Existen diferentes modelos teóricos, constructos e instrumentos para explorar variables salutogénicas de la personalidad que actúan como recursos protectores del trabajador ante el estrés psicosocial laboral. Las relaciones existentes entre estas variables permiten pensar en la posibilidad de construir un instrumento para su estudio. Objetivo: Elaborar un cuestionario de indicadores salutogénicos (BOAR) a partir de cuatro instrumentos que exploran: bienestar psicológico, autoestima, optimismo y personalidad resistente. Material y método: A 127 trabajadores de diferentes cargos se les aplicaron los cuestionarios originales y se realizó un análisis factorial con el método de los ejes principales para los 55 reactivos de los cuestionarios originales. Se seleccionaron aquellos con mayor carga factorial para cada uno de los factores extraídos -valores propios superiores a 1-, y según el contenido de los mismos, se conformó el BOAR con 27 ítems. Se aplicó a 281 trabajadores. Resultados: Se constataron asociaciones entre las variables; la autoestima centraliza las relaciones y, en especial, con el reto, componente de la resistencia. En correspondencia, la estructura factorial del BOAR no es evidente. Su consistencia interna es adecuada - Alpha de Cronbach = 0,8473- , lo que revela la homogeneidad del mismo. Conclusiones y recomendaciones: El BOAR es un cuestionario que permite explorar, en estudios de pesquisaje, indicadores salutogénicos en la población trabajadora. Aunque se demuestra su consistencia interna como instrumento, se requiere continuar su validación con un criterio externo y comprobar su estabilidad(AU)

Reflexiones bioéticas acerca del tráfico ilegal de especies en Colombia / Bioethics reflections about illegal trade of species in Colombia / Reflexões bioéticas sobre o tráfico ilegal de espécies na Colômbia

El tráfico ilegal de especies, si bien es un problema a nivel mundial, para Colombia resulta particularmente grave, si se tiene en cuenta que es el segundo país megadiverso y, por tanto, una buena parte de la vida del Planeta se encuentra sustentada desde el suelo colombiano, es decir, el país es el segundo reservorio genético de la humanidad. Una de las mayores implicaciones de ésta problemática, consiste en la pérdida de la diversidad generada por una fuerte presión hacia la extinción de especies, esto unido al deterioro del hábitat por rupturas en las cadenas tróficas tienen implicaciones que se pueden considerar como catastróficas no sólo a nivel local, sino en un sentido más amplio, a nivel global...

Illegal traffic of species is a well acknowledge International problem. In the of Colombia's It becomes particularly Ernst in that Colombia is the second mega-diverse country. Hence, a large part of life on Earth is placed within the Colombian territory, which makes of this country the second worldwide genetic reservoir for humankind. The most important implications of such a set of problems consist in the loss of diversity generated by the strong pressure on the extinction of species. This is united to the deterioration of the habitat due to the rupture of trophic chains which has serious consequences that can be considered as catastrophic not just on the local level but also in its largest worldwide level...

O tráfico ilegal de espécies, ainda que seja um problema de nível mundial, é particularmente grave para a Colômbia se considerarmos que é o segundo país megadiverso e, portanto, uma boa parte da vida do Planeta se encontra sustentada em solo colombiano, ou seja, o país é o segundo reservatório genético da humanidade. Uma das maiores implicações desta problemática consiste na perda da diversidade, gerada por uma forte pressão para a extinção de espécies. Isto, unido à deterioração do habitat por rupturas nas cadeias tróficas, tem implicações que podem ser consideradas catastróficas não apenas em nível local como, em um sentido mais amplo, em nível global...

Un estudio factorial en la psicotoxicidad por tolueno / A factorial study on psychotoxicity by tolueno

Se seleccionaron seis variables como posibles indicadores de la exposición habitual a una sustancia neurotóxica: el tolueno. Estas son: 1. edad, 2. tiempo de exposición al tóxico, 3. sintomatología referida, 4. funciones gestáticas y visomotoras, 5. niveles de ácido hipúrico, 6. niveles de creatinina. Se aplica una técnica multivariada, el análisis factorial clásico por el método centroide de Thurstone, y se determina la existencia de dos factores no puros. El factor I, denominado individualidad, nos muestras las saturaciones más altas en la edad, experiencia de trabajo y funciones perceptuales, y brinda el grado de asociación entre las mismas. El factor II, denominado síntomas referidos, está muy relacionado con los niveles de ácido hipúrico en orina. Se recomienda la utilización concatenada de estos indicadores en el diagnóstico de una posible intoxicación crónica por exposición al tolueno(AU)