Microplásticos en sedimentos costeros y marinos del litoral de la Región de Murcia y en dorada (Sparus aurata) como especie de interés comercial

[SPA] El plástico es uno de los materiales más utilizados en todo el planeta debido a su versatilidad y bajo coste de producción. Sin embargo, su durabilidad y la ineficiencia en la gestión y reciclado, han convertido a los desechos de este material en uno de los mayores contaminantes del medio marino, ya que una vez que llegan al mar tienden a agruparse en la superficie, donde se degradan en fragmentos más pequeños formando microplásticos, que pueden dispersarse por la columna de agua, quedar biodisponibles o acumularse en sedimentos. La presente Tesis Doctoral analiza la composición y abundancia de los microplásticos presentes en sedimentos costeros de la laguna del mar Menor, área de alto valor ambiental, social y económico de gran complejidad, y en el tracto gastrointestinal de 17 individuos de Sparus aurata (dorada) cuyas capturas se realizaron en esta laguna. Además, fuera del mar Menor, en sedimentos costeros y marinos de la playa semiurbana “Cala Cortina” localizada entre las dos dársenas del Puerto de Cartagena se analiza la presencia de estos microcontaminantes y su grado de meteorización en función de la distancia a la costa y a la profundidad. La extracción de los microplásticos se realizó utilizando una disolución de NaCl, aunque en las muestras de sedimento marino y dorada se añadió un proceso de digestión de la materia orgánica en KOH y H2O2 respectivamente. Posteriormente, las micropartículas aisaldas fueron identificadas mediante microscopia trinocular y espectofotometría infrarroja con transformada de Fourier. Los resultados obtenidos indican que la concentración media de microplásticos es mayor en el sedimento costero del mar Menor que en los sedimentos (marino y costero) de la playa del Mediterráneo analizada. Además, los microplásticos identificados en las muestras de sedimento y dorada del mar Menor se correspondieron principalmente con los polímeros LDPE y HDPE, mientras que en las muestras de sedimentos del Mediterráneo estaban constituidos por polímeros de PV, PE y PP. La concentración media de los microplásticos obtenidos en las muestras del mar Menor no presenta diferencias estadísticas significativas en función del grado de antropización de la playa, distancia a cauce de ramblas, subcuenca vertiente en la que se encuentran, forma de la playa, nivel de protección ambiental, sin embargo, son mayores en las muestras tomadas más lejos de la zona intermareal. Por su parte, las muestras de sedimentos del Mediterráneo muestran un gradiente ascendente en la concentración de microplasticos con el incremento de la profundidad para el sedimento marino, y a mayor distancia de la línea de marea alta para sedimento costero. Además, los índices de meteorización indican un efecto protector de la profundidad en relación a la degradación y oxidación de los polímeros y una intensificación de estos procesos cerca de la línea de marea alta. En el caso de las doradas, no se ha encontrado una correlación significativa entre los microplásticos ingeridos y el peso del individuo, longitud, peso estómago y peso intestino, aunque la media de microplásticos en el tracto gastrointestinal por kilogramo de individuo, ha sido superior a la registrada en la mayoría de los estudios del mar Mediterráneo para distintas especies. [ENG] Plastic is one of the most widely used materials in the world due to its versatility and low production cost. However, its durability and inefficient management and recycling have turned plastic waste into one of the major pollutants of the marine environment, since once it reaches the sea it tends to clump together on the surface, where it degrades into smaller fragments forming microplastics, which can be dispersed in the water column, become bioavailable or accumulate in sediments. This PhD analyzes the composition and abundance of microplastics in coastal sediments of the lagoon of the Mar Menor, an area of high environmental, social and economic value of great complexity, and in the gastrointestinal tract of 17 individuals of Sparus aurata (gilthead sea bream) whose catches were made in this lagoon. In addition, outside the Mar Menor, in coastal and marine sediments of the semi-urban beach "Cala Cortina" located between the two docks of the Port of Cartagena, the presence of these micropollutants and their degree of weathering is analyzed as a function of distance from the coast and depth. Microplastics extraction was performed using NaCl solution, although in the marine sediment and sea bream samples a process of digestion of organic matter in KOH and H2O2 was added, respectively. Subsequently, the isolated microparticles were identified by trinocular microscopy and Fourier transform infrared spectrophotometry. The results obtained indicate that the average concentration of microplastics is higher in the coastal sediment of the Mar Menor than in the sediments (marine and coastal) of the Mediterranean beach analyzed. In addition, the microplastics identified in the sediment and sea bream samples from the Mar Menor were mainly LDPE and HDPE polymers, whereas in the Mediterranean sediment samples they consisted of PV, PE and PP polymers. The average concentration of microplastics obtained in the samples from the Mar Menor does not show significant statistical differences depending on the degree of anthropization of the beach, distance from the wadi channel, sub-basin of the slope in which they are found, shape of the beach, level of environmental protection, however, they are higher in the samples taken further away from the intertidal zone. On the other hand, the Mediterranean sediment samples show an upward gradient in microplastics concentration with increasing depth for marine sediment, and at greater distance from the high tide line for coastal sediment. In addition, weathering indices indicate a protective effect of depth on polymer degradation and oxidation and an intensification of these processes near the high tide line. In the case of sea bream, no significant correlation has been found between microplastics ingested and individual weight, length, stomach weight and intestine weight, although the average number of microplastics in the gastrointestinal tract per kilogram of individual has been higher than that recorded in most studies in the Mediterranean Sea for different species.Escuela Internacional de Doctorado de la Universidad Politécnica de CartagenaUniversidad Politécnica de CartagenaPrograma de Doctorado en Tecnología y Modelización en Ingeniería Civil, Minera y Ambienta

Weathering indices of microplastics along marine and coastal sediments from the harbor of Cartagena (Spain) and its adjoining urban beach

Marine and coastal sediments from the harbor of Cartagena (Spain) and its adjoining beach were investigated regarding their microplastic burden. Fibers accounted for 47.62% and 61.66% in marine and coastal sediments, respectively, followed by films (31.43% and 18.76%) and fragments (20.95% and 18.65%). Polyvinyl (36.07%), polypropylene (21.31%), and polyethylene (18.03%) were isolated for marine sediments, and low-density polyethylene (40.71%), polypropylene (20.16%), and acrylate (11.37%) for coastal sediments. Highest concentrations were found in the deepest marine sediments (24.0 m) and in the furthest zone from the seashore for coastal sediments (18 m). Carbonyl index increased in the intermediate area (12.5 m) for marine sediments (0.51), whilst vinyl index was maximum for the deepest samples (1.94), reporting Norrish type I and II reactions, respectively. Coastal sediments collected close to the high tide line displayed the highest average values for both indices, 1.57 and 1.29, respectively, indicating a higher exposition to weathering variables.We thank Pedro Martínez for technical assistance. This work was financially supported by grant 20268/FPI/17 from Fundación Séneca assigned to Dr. Sonia Olmos and by Project Number 5813/19IQA from Cartagena Port Authority

Commercial gilthead seabream (Sparus aurata L.) from the Mar Menor coastal lagoon as hotspots of microplastic accumulation in the digestive system

This paper presents the results on the presence and characterization of microplastics (MP) in the gastrointestinal tract of gilthead seabream (Sparus aurata L.), a species of commercial interest from the Mar Menor coastal lagoon in Southeast Spain. This is the first time that microplastic ingestion is recorded in any species from this semi-enclosed bay. Stomach and intestine from a total of 17 specimens captured by local fishermen were processed, and microplastic particles and fibers found in all of them were displayed. Overall, 40.32% (279/692) of total isolated microparticles proved to be microplastics; i.e., <5 mm, as identified by FTIR spectroscopy. The average value by fish was 20.11 _ 2.94 MP kg1, corresponding to average concentrations of 3912.06 _ 791.24 and 1562.17 _ 402.04 MP by kg stomach and intestine, respectively. Four MP forms were isolated: fiber (71.68%), fragment (21.15%), film (6.81%), and microbead (0.36%), with sizes ranging from 91 _m to 5 mm, an average of 0.83 _ 0.04 mm, and no statistically significant differences between mean sizes in stomach and intestine samples (F-test = 0.004; p = 0.936). Nine polymer types were detected, although most of fibers remained unidentified because of their small size, the presence of polymer additives, or closely adhered pollutants despite the oxidizing digestion carried out to eliminate organic matter. No significant correlation was found between main biological parameters and ingested microplastics, and high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyethylene polypropylene (PEP), and polyvinyl (PV) were identified as the most abundant polymers. The average microplastic ingestion in this study area was higher than those reported in most studies within the Mediterranean Sea, and closely related to microplastic pollution in the surrounding area, although with a predominance of fiber form mainly due to fishery activities.This work was financed by Project 5345/18IQA (Technical University of Cartagena). Analyses carried out by Sonia Olmos were supported by a grant from Fundación Séneca (20268/FPI/17)

Elective cancer surgery in COVID-19-free surgical pathways during the SARS-CoV-2 pandemic: An international, multicenter, comparative cohort study

PURPOSE As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19–free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19–free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19–free surgical pathways. Patients who underwent surgery within COVID-19–free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19–free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score–matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19–free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION Within available resources, dedicated COVID-19–free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.

PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

Preoperative nasopharyngeal swab testing and postoperative pulmonary complications in patients undergoing elective surgery during the SARS-CoV-2 pandemic.

BACKGROUND: Surgical services are preparing to scale up in areas affected by COVID-19. This study aimed to evaluate the association between preoperative SARS-CoV-2 testing and postoperative pulmonary complications in patients undergoing elective cancer surgery. METHODS: This international cohort study included adult patients undergoing elective surgery for cancer in areas affected by SARS-CoV-2 up to 19 April 2020. Patients suspected of SARS-CoV-2 infection before operation were excluded. The primary outcome measure was postoperative pulmonary complications at 30 days after surgery. Preoperative testing strategies were adjusted for confounding using mixed-effects models. RESULTS: Of 8784 patients (432 hospitals, 53 countries), 2303 patients (26.2 per cent) underwent preoperative testing: 1458 (16.6 per cent) had a swab test, 521 (5.9 per cent) CT only, and 324 (3.7 per cent) swab and CT. Pulmonary complications occurred in 3.9 per cent, whereas SARS-CoV-2 infection was confirmed in 2.6 per cent. After risk adjustment, having at least one negative preoperative nasopharyngeal swab test (adjusted odds ratio 0.68, 95 per cent confidence interval 0.68 to 0.98; P = 0.040) was associated with a lower rate of pulmonary complications. Swab testing was beneficial before major surgery and in areas with a high 14-day SARS-CoV-2 case notification rate, but not before minor surgery or in low-risk areas. To prevent one pulmonary complication, the number needed to swab test before major or minor surgery was 18 and 48 respectively in high-risk areas, and 73 and 387 in low-risk areas. CONCLUSION: Preoperative nasopharyngeal swab testing was beneficial before major surgery and in high SARS-CoV-2 risk areas. There was no proven benefit of swab testing before minor surgery in low-risk areas

Delaying surgery for patients with a previous SARS-CoV-2 infection

Not availabl