Microplastics in European sea salts - An example of exposure through consumer choice and of interstudy methodological discrepancies.

Microplastics are contaminants of emerging concern, not least due to their global presence in marine surface waters. Unsurprisingly, microplastics have been reported in salts harvested from numerous locations. We extracted microplastics from 13 European sea salts through 30% H2O2 digestion and filtration over 5-µm filters. Filters were visually inspected at magnifications to x100. A subsample of potential microplastics was subjected to Raman spectroscopy. Particle mass was estimated, and human dose exposure calculated. After blank corrections, median concentrations were 466 ± 152 microplastics kg-1 ranging from 74 to 1155 items kg-1. Traditionally harvested salts contained fewer microplastics than most industrially harvested ones (t-test, p < 0.01). Approximately 14 µg of microplastics (< 12 particles) may be absorbed by the human body annually, of which a quarter may derive from a consumer choosing sea salt. We reviewed existing studies, showing that targeting different particle sizes and incomplete filtrations hinder interstudy comparison, indicating the importance of method harmonisation for future studies. Excess salt consumption is detrimental to human health; the hazardousness of ingesting microplastics on the other hand has yet to be shown. A portion of microplastics may enter sea salts through production processes rather than source materials.

Advances in Treatment of Frontotemporal Dementia.

In this review, the authors explored the clinical features of frontotemporal dementia (FTD), focusing on treatment. The clinical features of FTD are unique, with disinhibition, apathy, loss of empathy, and compulsions common. Motor changes occur later in the illness. The two major proteins that aggregate in the brain with FTD are tau and TDP-43, whereas a minority of patients aggregate FET proteins, primarily the FUS protein. Genetic causes include mutations in MAPT, GRN, and C9orf72. There are no medications that can slow FTD progression, although new therapies for the genetic forms of FTD are moving into clinical trials. Once a diagnosis is made, therapies should begin, focusing on the family and the patient. In the setting of FTD, families experience a severe burden associated with caregiving, and the clinician should focus on alleviating this burden. Advice around legal and financial issues is usually helpful. Careful consideration of environmental changes to cope with abnormal behaviors is essential. Most compounds that have been used to treat dementia of the Alzheimer's disease type are not effective in FTD, and cholinesterase inhibitors and memantine should be avoided. Although the data are scant, there is some evidence that antidepressants and second-generation antipsychotics may help individual patients.

Battling the known unknowns: a synoptic review of aquatic plastics research from Australia, the United Kingdom and China.

Plastic pollution is a global environmental and human health issue, with plastics now ubiquitous in the environment and biota. Despite extensive international research, key knowledge gaps ("known unknowns") remain around ecosystem-scale and human health impacts of plastics in the environment, particularly in limnetic, coastal and marine systems. Here we review aquatic plastics research in three contrasting geographic and cultural settings, selected to present a gradient of heavily urbanised (and high population density) to less urbanised (and low population density) areas: China, the United Kingdom (UK), and Australia. Research from each country has varying environmental focus (for example, biota-focussed studies in Australia target various bird, fish, turtle and seal species, while UK and China-based studies focus on commercially important organisms such as bivalves, fish and decapods), and uses varying methods and reporting units (e.g. mean, median or range). This has resulted in aquatic plastics datasets that are hard to compare directly, supporting the need to converge on standardised sampling methods, and bioindicator species. While all the study nations show plastics contamination, often at high levels, datasets are variable and do not clearly demonstrate pollution gradients.

Developing a systematic method for extraction of microplastics in soils.

Microplastics are an environmental issue of global concern. Although they have been found in a range of environments worldwide, their contamination in the terrestrial environment is poorly understood. The lack of standardised methods for their detection and quantification is a major obstacle for determining the risk they pose to soil environments. Here we present a systematic comparison of microplastic extraction methods from soils, taking into account the characteristics of the soil medium to determine the best methods for quantification. The efficiency of organic matter removal using hydrogen peroxide, potassium hydroxide and Fenton's reagent was measured. Soils with a range of particle size distribution and organic matter content were spiked with a variety of microplastic types. Density separation methods using sodium chloride, zinc chloride and canola oil were tested. Recovery efficiencies were calculated and the impact of the reagents on the microplastics was quantified using Attenuated Total Reflectance (ATR) Fourier Transform-Infrared (FTIR) spectroscopy. The optimal organic removal method was found to be hydrogen peroxide. The recovery efficiency of microplastics was variable across polymer types. Overall, canola oil was shown to be the optimal method for density separation, however, efficiency was dependent on the amount of organic matter in the soil. This outcome highlights the importance of including matrix-specific calibration in future studies considering a wide range of microplastic types, to avoid underestimation of microplastic contamination. We show here that methods for extracting microplastics from soils can be simple, cost-effective and widely applicable, which will enable the advancement of microplastic research in terrestrial environments.

Effects of the interaction between temperature and steroid hormones on gametogenesis and sex ratio in the European flat oyster (Ostrea edulis).

Throughout Europe, populations of Ostrea edulis have been in decline since the 1970s. Temperature has an important influence on physiological, biochemical and reproductive attributes of oysters. It is also the most easily modulated environmental factor in hatcheries, so it is useful to understand the implications of temperature variation in driving gametogenesis and sex development in a protandrous sequential hermaphrodites such as O. edulis. To understand the effect of temperature on gametogenesis and sex ratio, as well as the potential mechanism of sex determination through the role of steroid hormone homologues, oysters were exposed to three temperatures (10, 14, and 18 °C) for four months. Gametogenic stage and sex ratio were assessed histologically for each treatment. In parallel, concentrations of estradiol (E2)- and testosterone (T)- were determined in developing gonads. Our data show that by some biometric parameters, gametogenesis and sex ratio were significantly influenced by temperature during the experiment. There was a weak but significant correlation between E2 and T concentration during the treatments. However, and importantly, a direct relation between gonadal maturation, sex determination and hormones concentration was not found. These results suggest that gametogenesis and sex determination are predominantly affected by temperature in this species, and that steroids may not be actively involved as endogenous modulators in sex determination. Rising sea water temperatures and warmer condition through the year could cause an accelerated gametogenesis and skewed sex ratios in natural populations of O. edulis.

Evaluación genotóxica del agua del Río Grande (Antioquia, Colombia) mediante frecuencia de eritrocitos micronucleados de Brycon henni (Characiformes: Characidae) / Genotoxic evaluation of Río Grande (Antioquia, Colombia) water using micronucleus frequency in erythrocytes of Brycon henni (Characiformes: Characidae)

ResumenLa producción agrícola de monocultivo permanente de banano y plátano en la parte media del Río Grande (Turbo - Antioquia) requiere de la aplicación de diferentes plaguicidas. Prácticas inapropiadas en la producción y cultivos de plátano realizadas en esta región a menudo conllevan a contaminación con agroquímicos que llegan a este cuerpo de agua por procesos de lixiviación y escorrentía. Los peces son los vertebrados más utilizados como especies bioindicadoras de la calidad del agua porque son muy sensibles a la presencia de contaminantes en el ambiente. El objetivo de esta investigación fue comparar la frecuencia de eritrocitos micronucleados (EMN) en sangre periférica de ejemplares de peces sabaleta (Brycon henni) procedentes de dos estaciones del Río Grande que difieren en su grado de contaminación por agroquímicos. Se evaluó la frecuencia de EMN en sangre periférica de peces B. henni procedentes de cada estación durante dos épocas de lluvia de 2010 y dos época secas de 2011. Las muestras de sangre fueron obtenidas de la vena caudal, fijadas durante 24 horas y luego teñidas con Giemsa. La frecuencia de EMN fue significativamente mayor en el área impactada por agroquímicos. La frecuencia media de EMN fue mayor en la estación con impacto directo de agroquímicos (0.15±0.18) que en la estación poco alterada (0.06±0.08). Además, la frecuencia de EMN en B. henni fue significativamente mayor en la época seca. Los resultados de este estudio indican que el análisis de las EMN en B. henni puede ser recomendada como un método adecuado para la detección in situ de agentes genotóxicos en el ambiente.

Abstract:The permanent monoculture of bananas and plantains farming in the middle of Río Grande (Turbo - Antioquia) requires the application of a variety of pesticides. Inappropriate banana production practices in this region, have often led to waterbody pollution by agrochemicals from leachate and runoff processes. Currently, fish are the most common vertebrates used as bioindicators of water quality, because they are very sensitive to the presence of contaminants. Our main goal with this study was to compare the frequency of micronucleated erythrocytes (MNE) in peripheral blood specimens of fish Brycon henni, from two locations (polluted and unpolluted) in the Rio Grande. We evaluated the frequency of MNE in peripheral blood samples of fish B. henni from each location during two rainy seasons in 2010 and two dry seasons in 2011. Blood samples were collected, fixed for 24 h, and then were stained with Giemsa. Among results, we found that the median frequency of MNE was higher in the polluted site by agrochemical discharges (0.15±0.18), than in the unimpacted site (0.06±0.08). Furthermore, the frequency of MNE in B. henni during the dry season was highly significant for both locations. The results of this study indicated that the analysis of MNE in B. henni could be recommended as a suitable method for in situ detection of environmental genotoxins. Rev. Biol. Trop. 65 (1): 405-414. Epub 2017 March 01.

[Genotoxic evaluation of Río Grande (Antioquia, Colombia) water using micronucleus frequency in erythrocytes of Brycon henni (Characiformes: Characidae)]. / Evaluación genotóxica del agua del Río Grande (Antioquia, Colombia) mediante frecuencia de eritrocitos micronucleados de Brycon henna (Characiformes: Characidae).

The permanent monoculture of bananas and plantains farming in the middle of Río Grande (Turbo - Antioquia) requires the application of a variety of pesticides. Inappropriate banana production practices in this region, have often led to waterbody pollution by agrochemicals from leachate and runoff processes. Currently, fish are the most common vertebrates used as bioindicators of water quality, because they are very sensitive to the presence of contaminants. Our main goal with this study was to compare the frequency of micronucleated erythrocytes (MNE) in peripheral blood specimens of fish Brycon henni, from two locations (polluted and unpolluted) in the Rio Grande. We evaluated the frequency of MNE in peripheral blood samples of fish B. henni from each location during two rainy seasons in 2010 and two dry seasons in 2011. Blood samples were collected, fixed for 24 h, and then were stained with Giemsa. Among results, we found that the median frequency of MNE was higher in the polluted site by agrochemical discharges (0.15±0.18), than in the unimpacted site (0.06±0.08). Furthermore, the frequency of MNE in B. henni during the dry season was highly significant for both locations. The results of this study indicated that the analysis of MNE in B. henni could be recommended as a suitable method for in situ detection of environmental genotoxins.

Genotoxicidad sobre linfocitos humanos expuestos a PM10 de tres sitios del Valle de Aburrá (Antioquia) / Genotoxicity in human lymphocytes exposed to PM10 from three sites in the Valle de Aburrá (Antioquia)

Objetivo Evaluar la calidad del aire en tres sitios del Valle de Aburrá (Antioquia) a través de la determinación de la genotoxicidad del PM10 en linfocitos humanos. Métodos A partir del valor de referencia de PM10 para Colombia (50 μg/m3/año) se eligieron tres sitios del Valle de Aburrá con diferente promedio de PM10, Barbosa con 25 μg/m3, Corantioquia con 44 μg/m3y Facultad de Minas con 91 μg/m3. Los filtros de PM10 expuestos por 24 horas, se analizaron en la épocas de lluvia, transición y seca entre Julio de 2011 y abril de 2012. Con el extracto orgánico obtenido en cada filtro se trataron linfocitos humanos para evaluar in vitro el daño en el ADN por medio del ensayo Cometa Alcalino. Resultados Todos los sitios indujeron genotóxicidad altamente significativa (p< 0.001) respecto al control negativo, presentando el mayor daño durante la época de transición. Se observaron diferencias significativas (p<0.05) en la genotoxicidad inducida por el PM10 entre los tres sitios evaluados. Conclusiones Aunque los valores de PM10 reportados para Barbosa y Corantioquia fueron inferiores al nivel máximo permisible, se encontró actividad genotóxica del PM10 proveniente tanto de ellos como de Facultad de Minas cuyo valor de PM10 es superior a la norma. Estos resultados indican que únicamente el monitoreo fisicoquímico del material particulado es insuficiente para evaluar el riesgo relativo sobre la población expuesta. En consecuencia, estos estudios deben ser complementados con biomarcadores de genotoxicidad como el ensayo cometa.(AU)

Objective Assessing air quality by determining PM10 genotoxicity in human lymphocytes at three locations in the Valle de Aburrá (Antioquia department). Methods Three sites were chosen in the Valle de Aburrá (Barbosa, Corantioquia and the School of Mines) using Colombian reference (50 g/m3) and PM10content values, having annual low (25 mg /m3), medium (44 ug/m3) and high PM10 average (91 ug/m3). PM10filters were analyzed during three different seasons between 2011 and 2012: rainy, transitional and dry. Human lymphocytes were treated with the organic extract obtained from each filter to evaluate DNA damage using an alkaline comet assay. Results Genotoxicity was found to be highly significant (p<0.001) in all cases, compared to the negative control. The highest damage (six times) was seen in material from the School of Mines and during the transitional period. Differences were found between material from Barbosa and Corantioquia regarding that from the School of Mines concerning the induction of damage. Conclusions Although the PM10 values reported for Barbosa and Corantioquia were below the maximum permitted level, genotoxic activity was found for PM10from both sites as well as for the School of Mines. These results show that physical-chemical monitoring of particulate matter is not enough for assessing the exposed population's relative risk. Such analysis should thus be accompanied by using genotoxicity biomarkers, such as the comet assay.(AU)

[Genotoxicity in human lymphocytes exposed to PM10 from three sites in the Valle de Aburrá (Antioquia)]. / Genotoxicidad sobre linfocitos humanos expuestos a PM10 de tres sitios del Valle de Aburrá (Antioquia).

OBJECTIVE: Assessing air quality by determining PM(10) genotoxicity in human lymphocytes at three locations in the Valle de Aburrá (Antioquia department). METHODS: Three sites were chosen in the Valle de Aburrá (Barbosa, Corantioquia and the School of Mines) using Colombian reference (50 g/m3) and PM(10) content values, having annual low (25 mg /m3), medium (44 ug/m3) and high PM(10) average (91 ug/m3). PM10filters were analyzed during three different seasons between 2011 and 2012: rainy, transitional and dry. Human lymphocytes were treated with the organic extract obtained from each filter to evaluate DNA damage using an alkaline comet assay. RESULTS: Genotoxicity was found to be highly significant (p<0.001) in all cases, compared to the negative control. The highest damage (six times) was seen in material from the School of Mines and during the transitional period. Differences were found between material from Barbosa and Corantioquia regarding that from the School of Mines concerning the induction of damage. CONCLUSIONS: Although the PM10 values reported for Barbosa and Corantioquia were below the maximum permitted level, genotoxic activity was found for PM10f rom both sites as well as for the School of Mines. These results show that physical-chemical monitoring of particulate matter is not enough for assessing the exposed population's relative risk. Such analysis should thus be accompanied by using genotoxicity biomarkers, such as the comet assay.