More than just sweet: current insights into microplastics in honey products and a case study of Melipona quadrifasciata honey.

Honey, traditionally known as a pure and natural substance, has become an unexpected reservoir for microplastic contamination. This study consisted of an experimental investigation to assess the occurrence of microplastics in honey produced by Melipona quadrifasciata, a native bee species in Brazil. Our investigation covers eight areas (one sample per area), including built and vegetated areas located in São Paulo city, Brazil, to understand the distribution of microplastics in these environments. Honey samples (10 mL) were collected using a syringe and sent to the laboratory for further analysis. Microplastics extracted from honey samples were characterized under a stereomicroscope to determine their size, color, and morphology. Also, the polymer type was determined by FTIR analysis. All honey samples (100%) showed microplastics. The predominant particles displayed a fiber shape with a size below 299 µm and a transparent color and were primarily composed of polypropylene. Their concentrations ranged from 0.1 to 2.6 particles per mL of honey, raising concerns about their potential impact on bee populations and human consumers. This study underscores the need for further research on the sources and implications of microplastic contamination in Melipona quadrifasciata honey, shedding light on the broader issue of environmental plastic pollution and its impact on pollinators.

Unveiling the hidden threat of microplastics to coral reefs in remote South Atlantic islands.

The widespread presence of marine microplastics (< 5 mm) is a significant concern, as it may harm marine biodiversity and ocean ecosystems. Corals' capacity to ingest microplastics has emerged as a significant threat to reef ecosystems, owing to the detrimental physiological and ecological effects it can trigger. The extent of the impact of microplastics on Brazilian corals remains unclear and this study aimed to investigate its distribution and characteristics in four coral species: Favia gravida, Mussismilia hispida, Montastrea cavernosa, and Siderastrea stellata, found in the Trindade and Martim Vaz Islands - the most isolated archipelago of Brazil, located about 1200 km (680 miles) east of the coast. This study aims to reveal the extent of microplastic distribution in the coral reef environment, assess the amount of microplastics in different coral species, and compare each species' capacity to adhere and accumulate microplastics. A high concentration of ingested and adhered microplastics was detected in all coral species evaluated in the present study. No significant differences were observed in the sampling points which indicates that although the sampling points are located at different distances from the coast, the microplastic pollution is equally distributed in the region. Polyethylene (PE), polyvinyl chloride (PVC), polypropylene (PP), poly(methyl methacrylate) (PMMA), Rayon, and Nylon particles were detected, with a predominance of PE (45.5 %). No significant differences in microplastic concentration were detected among the various species and locations studied. Our research presents findings that demonstrate the extensive occurrence of microplastic contamination in coral colonies located on remote islands.

Biological responses of Chironomus sancticaroli to exposure to naturally aged PP microplastics under realistic concentrations.

Microplastic (MP) is yet another form of chronic anthropogenic contribution to the environment. MPs are plastic particles (<5 mm) that have been widely found in the most diverse natural environments, but their real impacts on ecosystems are still under investigation. Here, we studied the toxicity of naturally aged secondary polypropylene (PP) MPs after constant exposure to ultraviolet radiation (26 µm) to the third instar larvae of Chironomus sancticaroli, a dipteran species. The concentrations tested were 13.5; 67.5; and 135 items g-1 of dry sediment. C. sancticaroli organisms were investigated for fragment ingestion, mortality and changes in enzymatic biomarkers after 144 h of exposure. The organisms were able to ingest MPs from the first 48 h, and the amount of items internalized was dose-dependent and time-dependent. Overall, the results show that mortality was low, being significant at the lowest and highest concentrations (13.5 and 135 items g-1). Regarding changes in biochemical markers, after 144 h MDA and CAT activities were both significantly altered (increased and reduced, respectively), while SOD and GST levels were unchanged. In the present study, naturally aged polypropylene MPs induced biochemical toxicity in C. sancticaroli larvae, with toxicity being higher according to exposure time and particle concentration.

Parasite detection in sand from bays on the north coast of São Paulo state, Brazil

Soil contamination by protozoan parasites and soil-transmitted helminths (STH) is common in beach sand due to a number of factors such as pets, pluvial water, garbage, etc. These pathogens may cause many diseases in humans and animals and become a public health problem. Thus, systematic evaluation and inspection are necessary to develop control strategies regarding public contamination. For this purpose, our aims were to evaluate the parasitic profile of sandy soils on an urban beach and an untouched beach and correlate this with environmental and seasonal characteristics in Ubatuba, Brazil, in two seasons (winter and summer). 132 soil samples were collected for parasite analysis utilizing Rugai's method and the sedimentation adapted method. Our results showed positivity in 62% of the samples for at least one parasite in the urban beach and no parasitic structures on the untouched beach. The positivity was higher in summer (85%) than in winter (51.7%). All samples were positive for both, helminths and protozoa. Seasonal influence was noted regarding the presence of STH while for protozoa this influence was not observed. The parasitic structures most found were larvae of hookworms (35%) and Toxocara eggs (31.7%). We also noted the presence of Strongyloides sp, Ascaris lumbricoides, coccidia, Dipylidium caninum, Entamoeba hystolitica/dispar, Endolimax nana, Entamoeba coli, Giardia sp, Toxascaris leonina, Trichuris sp and Dibothricephalus latus. There was a positive correlation between temperature and the presence of STH in the sand samples. Most of the collection sites on the urban beach presented dogs or canine traces and garbage in both seasons. There was an association between the presence of dogs or their traces and parasitic structures. In conclusion, seasonality, urbanization and the presence of pets on beaches can potentially favor environmental contamination by parasites increasing the risk of transmission of zoonotic and parasitic diseases.

Avaliação da eficiência de um índice de estado trófico na determinação da qualidade da água de reservatórios para abastecimento público / Assessment of the efficiency of a trophic state index in determining the water quality of public water supply reservoirs

RESUMO O objetivo deste estudo consiste na avaliação da eficácia do uso de um índice de estado trófico (IET) como ferramenta na análise da qualidade das águas de três reservatórios. O IET foi calculado baseado na transparência do reservatório e nas concentrações de clorofila-a e fósforo total (P total). Para identificar a correlação do uso do solo com a poluição aquática das represas, o IET calculado para cada represa foi comparado ao mapeamento temático de cobertura do solo com base em imagens do satélite Landsat TM 5 do ano de 2010. A análise dos componentes principais (ACP), focada na correlação dos dados, foi realizada utilizando o software PAST®, versão 2.16. Inicialmente, o comportamento dos parâmetros associados ao IET foi avaliado de forma isolada (P total, clorofila-a e transparência) sobre os reservatórios. Em seguida, foram aplicados à ACP os demais parâmetros físicos e químicos associados à qualidade da água dos reservatórios (sem o IET). Por fim, todos os parâmetros foram submetidos à ACP (IET e todos os outros parâmetros em conjunção). O IET utilizado nesta pesquisa demonstrou ser autossuficiente na predição da qualidade de água com a utilização de apenas três parâmetros (P total, clorofila-a e transparência). A análise das imagens de satélite, em conjunto com os dados provenientes do IET, foi suficiente para apontar a redução da qualidade das águas por fontes pontuais de poluição, mesmo em ambientes com maior cobertura vegetal preservada.

ABSTRACT The aim of this study consists in the evaluation of the trophic state index (IET) efficacy as a tool in the water quality analysis of three reservoirs. The IET was calculated based on water transparency in the reservoir and on the surface concentrations of chlorophyll-a and total phosphorus (total P). To identify the correlation of the soil use with the reservoir aquatic pollution, the IET calculated for each reservoir was compared to the thematic mapping of land cover based on Landsat TM 5 satellite images from 2010. The main components analysis (ACP), focused on data correlation, was made using the software PAST®, version 2.16. Initially, the behavior of the parameters associated with the IET was evaluated alone (total P, chlorophyll-a and transparency) on the reservoirs. Then, the other chemical and physical parameters associated with the reservoirs water quality (without the IET) were applied to the ACP. Finally, all the parameters underwent the ACP (IET and all the other parameters in conjunction). The IET used in this research seemed to be self-sufficient in the prediction of water quality using only three parameters (total P, chlorophyll-a and transparency). The satellite images analysis, in conjunction with the IET data, was sufficient to point out the water quality reduction by punctual sources of pollution even in environments with larger preserved vegetal coverage.