Compliance with the ban of lead ammunition in a Mediterranean wetland, the Ebro delta

Trabajo presentado por Núria Vallverdú Coll para la obtención del grado de Máster universitario en investigación básica y aplicada en recursos cinegéticos, realizado en el Instituto de Investigación en Recursos Cinegéticos (IREC, CSIC-UCLM-JCCM).[EN]: The ingestion of lead (Pb) shot used for hunting continues being the main cause of Pb poisoning in waterfowl. In the Ebro delta (Spain), protected wetlands are surrounded by rice fields where waterbirds feed, and where Pb ammunition is still allowed. High Pb shot densities in sediments, and in turn high ingestion prevalence in waterfowl, have been detected. The use of Pb ammunition and the accumulation of Pb by birds after shot ingestion may pose a risk for human health due to consumption of contaminated meat. We assessed the degree of compliance with the ban on Pb ammunition in the Ebro delta wetlands, and studied the effect of the ban on the prevalence of Pb shot ingestion in waterbirds and on Pb levels in game meat. Waterfowl carcasses were collected and X‐rayed from hunting bags (2007‐2011) to determine the percentage of Pb and non‐toxic embedded shot. Concentrations of Pb were analyzed in livers and muscles. In addition, gizzards were collected from hunting bags (2007‐2012) and examined to determine the percentage of Pb shot ingestion. During the first study season minimum hunter compliance, estimated as the percentage of waterbirds having only embedded steel shot (the non‐toxic alternative) was 48.75%, while 26.88% of birds had only embedded Pb shot (minimum hunter noncompliance). These values changed in the subsequent seasons to 68.95% and 1.13%, respectively. The little compliance detected during the first study season led local administration to notify hunters that a total prohibition of hunting in protected wetlands would enter into force if the prohibition was not observed. Pb ingestion prevalence in 2007‐2008 (28.6%) was not different from the pre‐ban value (30.2%), but decreased significantly to values below 17.9% in the following seasons. Birds continue ingesting Pb shot at a relative high proportion, although their prohibition slowly contributes to reduce prevalence of ingestion. Pb muscle concentrations decreased significantly after the ban, in spite of which most species present individuals with Pb liver and muscle concentrations over the maximum safety limits. Whereas muscle Pb levels were determined by the presence of both ingested and embedded shot (all p<0.001), liver levels largely depended on ingested shot (p<0.001). Thus, besides restrictions in Pb ammunition use, additional mechanisms to reduce Pb ingestion prevalence in waterfowl are necessary to reduce risks for human consumers.[ES]: La ingestión de perdigones de plomo (Pb) utilizados para la caza sigue siendo la principal causa de intoxicación en aves acuáticas. En el delta del Ebro (España), los humedales protegidos se encuentran rodeados por campos de arroz donde muchas aves acuáticas se alimentan, y donde todavía está permitido el uso de munición de Pb, habiéndose encontrado altas densidades de perdigones de Pb en los sedimentos, así como una elevada prevalencia  de ingestión de perdigones de Pb en aves acuáticas. El uso de munición de Pb y la  acumulación de Pb en los tejidos de las aves después de la ingestión de perdigones puede suponer un riesgo para la salud humana debido al consumo de carne contaminada. Se evaluó el grado de cumplimiento de la prohibición de la munición de Pb en los humedales protegidos del Delta del Ebro, y se estudió el efecto de la prohibición en la prevalencia de ingestión de perdigones de Pb en las aves acuáticas y en los niveles de Pb en la carne de caza. Se obtuvieron cadáveres de aves acuáticas de las bolsas de caza (2007‐2011) y se tomaron radiografías para determinar el porcentaje de perdigones de Pb y de perdigones no tóxicos incrustados. Se analizaron las concentraciones de Pb en hígado y en músculo. Además, se obtuvieron mollejas de las bolsas de caza (2007‐2012) y se examinaron para determinar el porcentaje de ingestión de perdigones de Pb. Durante la primera temporada del estudio, el cumplimiento mínimo, estimado como el porcentaje de aves acuáticas que tienen únicamente perdigones de acero incrustados (la alternativa no tóxica) fue del 48,75%, mientras que el 26,88% de las aves presentaron únicamente perdigones de Pb incrustados (incumplimiento mínimo). Estos valores fueron del 68,95% y 1,13%, respectivamente, en las temporadas posteriores. El bajo nivel de cumplimiento detectado durante la primera temporada de estudio llevó a las autoridades locales a amenazar a los cazadores con una prohibición total de la caza en los humedales protegidos si no respetaban la prohibición. La ingestión de perdigones de Pb en el período 2007‐2008 (28,6%) no fue diferente al valor pre‐prohibición (30,2%), pero disminuyó significativamente a valores por debajo del 17,9% en las siguientes temporadas. Las aves acuáticas siguen ingiriendo perdigones de Pb en una proporción relativamente alta, aunque su prohibición contribuye lentamente a una reducción de la prevalencia de ingestión. Las concentraciones de Pb en músculo disminuyeron significativamente después de la prohibición, a pesar de que la mayoría de las especies presentaron individuos con concentraciones de Pb por encima de los límites máximos de seguridad tanto en hígado como en músculo. Mientras que los niveles musculares de Pb estuvieron determinados por la presencia tanto de perdigón ingerido como de perdigón incrustado (ambos p<0,001), en el caso del hígado las concentraciones dependieron en gran medida de la presencia de perdigones ingeridos (p <0,001). En consecuencia, además de las restricciones en el uso de munición de Pb, son necesarios mecanismos adicionales para reducir la prevalencia de ingestión de Pb en aves acuáticas y así reducir los riesgos en la salud humana por parte de los consumidores.Este estudio es parte de los Proyectos CGL2007‐62797 y CGL2010‐17030 del Plan Nacional de I+D. Durante la realización de este Trabajo de Fin de Máster del Máster Universitario en Investigación Básica y Aplicada en Recursos Cinegéticos he disfrutado de una beca predoctoral FPI financiada por el Ministerio de Economía y Competividad y el Fondo Social Europeo (ref. BES‐2011‐045670).Peer reviewe

Agriculture, Food and Natural Resources Handbook 2011

The use of lead (Pb) ammunition in the form of shot pellets has been identified as a Pb exposure risk in wildlife and their human consumers. We explore the hypothesis that Pb shot ban enforcement reduces the risk of avian Pb poisoning as well as Pb exposure in game meat consumers. We assessed compliance with a partial ban on Pb shot commencing in 2003 by examination of 937 waterbirds harvested by hunters between 2007 and 2012 in the Ebro delta (Spain). Prevalence of Pb shot ingestion was determined, as were Pb concentrations in liver and muscle tissue to evaluate the potential for Pb exposure in game meat consumers. Hunted birds with only embedded Pb shot (no steel) declined from 26.9% in 2007–08 to < 2% over the following three hunting seasons after ban reinforcement. Pb shot ingestion in mallards decreased from a pre-ban value of 30.2% to 15.5% in the post-ban period. Liver Pb levels were predominantly defined by the presence of ingested shot, whereas muscle levels were defined by the presence of both ingested and embedded shot. Only 2.5% of mallard muscle tissue had Pb levels above European Union regulations for meat (0.1 μg/g wet weight) in the 2008–09 season, when Pb shot ingestion prevalence was also at a minimum (5.1%). Effective restrictions in Pb ammunition use have a dual benefit since this reduces Pb exposure for game meat consumers due to embedded ammunition as well as reducing Pb poisoning in waterbirds

Parasites of the reintroduced Iberian Lynx (Lynx pardinus) and Sympatric Mesocarnivores in Extremadura, Spain

Research Areas: MicrobiologyABSTRACT - The Iberian lynx (Lynx pardinus) is one of the most endangered felid species in the world. Conservation efforts have increased its population size and distribution and reinforced their genetic diversity through captive breeding and reintroduction programmes. Among several threats that the Iberian lynx faces, infectious and parasitic diseases have underlined effects on the health of their newly reintroduced populations, being essential to identify the primary sources of these agents and assess populations health status. To achieve this, 79 fresh faecal samples from Iberian lynx and sympatric mesocarnivores were collected in the reintroduction area of Extremadura, Spain. Samples were submitted to copromicroscopic analyses to assess parasite diversity, prevalence, and mean intensity of parasite burden. Overall, 19 (24.1%, ±15.1–35.0) samples were positive for at least one enteric parasite species. Parasite diversity and prevalence were higher in the Iberian lynx (43.8%) compared with the others mesocarnivores under study (e.g., the red fox Vulpes vulpes and the Egyptian mongoose Herpestes ichneumon). Ancylostomatidae and Toxocara cati were the most prevalent (15.6%) parasites. Obtained results revealed that Iberian lynx role as predator control might have reduced parasite cross-transmission between this felid and mesocarnivores due to their decreasing abundances. Surveillance programs must include regular monitoring of this endangered felid, comprising mesocarnivores, but also domestic/feral and wild cat communities.info:eu-repo/semantics/publishedVersio

Parasites of the Reintroduced Iberian Lynx (Lynx pardinus) and Sympatric Mesocarnivores in Extremadura, Spain.

The Iberian lynx (Lynx pardinus) is one of the most endangered felid species in the world. Conservation efforts have increased its population size and distribution and reinforced their genetic diversity through captive breeding and reintroduction programmes. Among several threats that the Iberian lynx faces, infectious and parasitic diseases have underlined effects on the health of their newly reintroduced populations, being essential to identify the primary sources of these agents and assess populations health status. To achieve this, 79 fresh faecal samples from Iberian lynx and sympatric mesocarnivores were collected in the reintroduction area of Extremadura, Spain. Samples were submitted to copromicroscopic analyses to assess parasite diversity, prevalence, and mean intensity of parasite burden. Overall, 19 (24.1%, ±15.1-35.0) samples were positive for at least one enteric parasite species. Parasite diversity and prevalence were higher in the Iberian lynx (43.8%) compared with the others mesocarnivores under study (e.g., the red fox Vulpes vulpes and the Egyptian mongoose Herpestes ichneumon). Ancylostomatidae and Toxocara cati were the most prevalent (15.6%) parasites. Obtained results revealed that Iberian lynx role as predator control might have reduced parasite cross-transmission between this felid and mesocarnivores due to their decreasing abundances. Surveillance programs must include regular monitoring of this endangered felid, comprising mesocarnivores, but also domestic/feral and wild cat communities.This research was funded by the European Union through its LIFE project Life + IBERLINCE (LIFE + 10NAT/ES/570) “Recuperación de la distribución histórica del lince ibérico (Lynx pardinus) en España y Portugal”. R. T. Torres is funded by national funds (OE), through FCT—Fundação para a Ciência e a Tecnologia, I.P., in the scope of the framework contract foreseen in the numbers 4, 5, and 6 of the article 23, of the Decree-Law 57/2016, of 29 August, changed by Law 57/2017, of 19 July. Thanks are due to FCT/MCTES for the financial support to CESAM (UIDP/50017/2020 + UIDB/50017/2020) and CIISA Project UIDB/00276/2020 through national funds.S

The evolution of the ventilatory ratio is a prognostic factor in mechanically ventilated COVID-19 ARDS patients

Background: Mortality due to COVID-19 is high, especially in patients requiring mechanical ventilation. The purpose of the study is to investigate associations between mortality and variables measured during the first three days of mechanical ventilation in patients with COVID-19 intubated at ICU admission. Methods: Multicenter, observational, cohort study includes consecutive patients with COVID-19 admitted to 44 Spanish ICUs between February 25 and July 31, 2020, who required intubation at ICU admission and mechanical ventilation for more than three days. We collected demographic and clinical data prior to admission; information about clinical evolution at days 1 and 3 of mechanical ventilation; and outcomes. Results: Of the 2,095 patients with COVID-19 admitted to the ICU, 1,118 (53.3%) were intubated at day 1 and remained under mechanical ventilation at day three. From days 1 to 3, PaO2/FiO2 increased from 115.6 [80.0-171.2] to 180.0 [135.4-227.9] mmHg and the ventilatory ratio from 1.73 [1.33-2.25] to 1.96 [1.61-2.40]. In-hospital mortality was 38.7%. A higher increase between ICU admission and day 3 in the ventilatory ratio (OR 1.04 [CI 1.01-1.07], p = 0.030) and creatinine levels (OR 1.05 [CI 1.01-1.09], p = 0.005) and a lower increase in platelet counts (OR 0.96 [CI 0.93-1.00], p = 0.037) were independently associated with a higher risk of death. No association between mortality and the PaO2/FiO2 variation was observed (OR 0.99 [CI 0.95 to 1.02], p = 0.47). Conclusions: Higher ventilatory ratio and its increase at day 3 is associated with mortality in patients with COVID-19 receiving mechanical ventilation at ICU admission. No association was found in the PaO2/FiO2 variation

Immunotoxic and reproductive effects of lead on avifauna affected by shot ingestion

La ingestión de perdigones de plomo procedentes de la munición de caza es una causa común de intoxicación en aves acuáticas1. A pesar de que el uso de munición de plomo fue prohibido en los humedales españoles protegidos2 en 2001, los perdigones de plomo pueden permanecen intactos durante décadas en los sedimentos, y por lo tanto se mantiene el riesgo de intoxicación. Esto significa que el envenenamiento por plomo sigue siendo un problema importante en cuanto a la conservación de las aves acuáticas incluso en zonas protegidas, que puede producir alteraciones fisiológicas y de comportamiento, así como también una amplia gama de efectos subletales o incluso la muerte. Aunque tanto la prevalencia en la ingestión perdigones como la consecuente mortalidad debido a la intoxicación por plomo han sido ampliamente descritas en aves silvestres3, existe una gran falta de conocimiento acerca de los efectos subletales derivados de exposiciones a dosis más bajas de plomo. El estudio de estos efectos subletales que pueden pasar inadvertidos constituye el tema central de este trabajo. Esta tesis tiene como objetivo estimar los efectos subletales del plomo en las aves considerando funciones relevantes para el individuo, así como para la dinámica de la población, tales como la inmunidad y la reproducción. La implicación del estrés oxidativo en la patogenia del plomo y los efectos adversos producidos sobre estas dos funciones se utilizó como el punto de encuentro entre todas las respuestas analizadas. Contenido de la investigación Para lograr estos objetivos, en primer lugar se evaluó el grado de cumplimiento de la prohibición del uso de la munición de plomo en un humedal protegido español, el delta del Ebro, y sus consecuencias en cuanto a la prevalencia de ingestión de perdigones de plomo en aves acuáticas y en los niveles de exposición al plomo en personas consumidoras de carne de caza. En segundo lugar, se estudiaron posibles alteraciones inmunológicas y reproductivas inducidas por el plomo en aves acuáticas silvestres del delta del Ebro, considerando el estrés oxidativo como un mecanismo implicado en la toxicidad del plomo. Al mismo tiempo, se estudiaron los efectos de una exposición subletal al plomo en componentes más específicos del sistema inmune y la reproducción bajo condiciones experimentales para comprender mejor estos mecanismos. Nueve años después de la prohibición de los perdigones de plomo en el delta del Ebro, se encontró una reducción en los niveles de exposición tanto en aves acuáticas como en consumidores de carne de caza. Sin embargo, la prohibición no supuso una eliminación total del riesgo de exposición. Aunque los niveles de plomo en sangre de patos silvestres (Anas platyrhynchos) capturados en el delta del Ebro se redujeron 9 años después de la prohibición, una proporción significativa de individuos de esta zona todavía se encuentra afectada por el envenenamiento por plomo. Por otra parte, estos niveles de exposición al plomo se asociaron con una serie de efectos relacionados con la inducción de estrés oxidativo, un deterioro de la inmunidad constitutiva y la reducción de la coloración en patos macho. También se demostró que la ingestión de perdigones puede dar lugar a la transmisión materna de plomo a la descendencia a través de los huevos. Los niveles más altos de exposición se asociaron con una disminución de la supervivencia, la inducción de estrés oxidativo y la alteración de desarrollo de la función inmune de los patitos. En condiciones experimentales, se encontraron varios efectos inducidos por el plomo que variaron según la estación del año y el género en la respuesta inmune y la coloración en perdices rojas (Alectoris rufa). Los subsiguientes experimentos mostraron que la exposición a plomo indujo la producción de huevos más pesados y más grandes, que dieron lugar a pollos más pesados, y se redujo el éxito de eclosión de los huevos. En los machos, la exposición a plomo disminuyó integridad acrosómica y la motilidad de los espermatozoides a dosis altas, y aumentó el vigor de los espermatozoides a dosis bajas, pero no afectó la viabilidad del esperma, la concentración, o la fertilidad. Conclusión A pesar del buen grado de cumplimiento de la prohibición del uso de la munición de plomo en el delta del Ebro, la caza legal con plomo en las áreas de alimentación en las que su uso no está restringido así como la gran accesibilidad de los perdigones acumulados en el medio ambiente siguen induciendo efectos subletales en las aves silvestres que pueden tener efectos negativos a nivel de población, y todavía suponen un riesgo para los consumidores de carne de caza. Esta tesis es un paso adelante para la comprensión de los efectos y mecanismos de la exposición subletal al plomo en distintas funciones relevantes y relacionadas entre sí, así como las consiguientes respuestas compensatorias que resultan de estas alteraciones en las aves

Lead poisoning of waterfowl in Spain: conservation efforts, trend of prevalences and implications on game meat safety

Resumen del trabajo presentado a la International Conference on Hunting for Sustainability: "Ecology, Economics and Society", celebrada en Ciudad Real (España) del 27 al 29 de marzo de 2012.The prevalence of lead (Pb) shot ingestion in waterfowl hunted in Spanish wetlands around the Mediterranean coast during the 1990s was as high as 30-39 % in mallard (Anas platyrhynchos), 69 % in common pochard (Aythya ferina) and 74 % in northern pintail (Anas acuta). Lead shot use was banned in protected wetlands in Spain in 2001, however, this was not fully implemented in the Ebro delta until 2003. Here, we show results for four hunting seasons (2007-2011) where shot wintering waterfowl (n = 503) from this wetland were monitored. The type of embedded shot present in hunted birds was studied by X-ray and dissection. The prevalence of Pb shot ingestion was studied by gizzard examination. Ban compliance was relatively low in 2007-08, i.e., 26.9 % of birds had embedded Pb shot, 10.6 % had Pb and steel shot, 48.8 % had steel shot, and 13.8 % had no shot. After these results were produced, the ban was reinforced and compliance subsequently increased with less than 5% of birds with only Pb shot. However, 22.9% of harvested birds contained embedded Pb and steel shot in 2010-11. The prevalence of Pb shot ingestion in mallards in 2007-08 (28.6%) was comparable to the pre-ban prevalence (30.2 %), but, it was significantly higher than in subsequent seasons (in 2008-09: 5.1 %; in 2009-10: 13.8 %; in 2010-11: 13.5%). In the last year of the study, a significant proportion of birds still had embedded Pb shot and/or ingested Pb shot in their gizzards. This may be because the ban was not implemented in unprotected rice fields, where the majority of ducks often feed. By extending the ban to all waterfowl hunting (not only that undertaken in protected wetlands) the risk of Pb poisoning in waterfowl can be greatly reduced. Game meat Pb levels were above maximum residue levels according to EU regulation for livestock meat in birds that had ingested Pb shot and birds killed with Pb ammunition. A significant reduction in game meat Pb levels was observed with the implementation of the use of steel shot.Peer Reviewe

Are immunotoxic effects of lead shot ingestion linked to oxidative stress?

Resumen del trabajo presentado al Society of Environmental Toxicology and Chemistry Europe 24th Annual Meeting, celebrado en Basel (Suiza) del 11 al 15 de mayo de 2014.The ingestion of lead (Pb) shot used for hunting constitutes the main cause of Pb poisoning in avifauna, but very little is known about the sublethal effects on birds and their consequences at a population level. We studied the relationship between Pb shot ingestion, oxidative stress biomarkers and the immune function in red-legged partridge (Alectoris rufa). Partridges (n=60) were housed in pairs and assigned to three experimental groups: Control (no shot), low dose and high dose. Pb concentration and δ-aminolevulinic acid dehydratase (δ-ALAD) activity, were determined in blood. Malondialdehyde concentration (MDA), total glutathion levels (GSH) and superoxide dismutase activity (SOD) were quantified in red blood cells homogenates. Vitamins (retinol, α-tocopherol) and carotenoid (lutein) levels were analyzed in plasma. Carotenoid-based coloration was studied by digital photographs and beak and eye ring spectrophotometry. Cell-mediated immune and humoral responses were studied using the phytohemagglutinin (PHA)-skin test and the haemagglutination test after antigen injection, respectively. Acute-phase and antibacterial proteins were measured in plasma. Constitutive immune response was tested determining bactericide activity of fresh whole blood. A negative relationship between Pb concentration and δ-ALAD was found. Pb exposure increased levels of GSH and the primary inflammatory response to PHA. In females, δ-ALAD activity was positively correlated with intensitiy of carotenoid-based red coloration and with relative amount of the eye ring area pigmented by carotenoids. GSH concentration was positively associated with blood Pb concentration. Cellular immune response increased with Pb exposure, while humoral immune response decreased. Exposure to Pb in males decreased retinol and lutein levels in plasma. Antioxidant mechanisms appear to be affected by Pb exposure in a different way in females and males. Females may show a hormetic response with the increase of GSH and enhanced cellular immune respose, but at the cost of a loss on carotenoid ornamentation and a reduced humoral immune response. Males exposed to Pb maintained the pigmentation of ornaments and the competence of both immune functions, but showed a more marked decrease of plasma antioxidants. This may reflect a handicap of the carotenoid-antioxidant allocation trade-off in males between the expression of sexual signals and the immunitary response or other oxidative stress-sensitive functions.Peer Reviewe

Heavy metals, oxidative stress and immune function in common moorhens from natural and artificial wetlands

Presentado al Society of Environmental Toxicology and Chemistry (SETAC) Europe 26th Annual Meeting, celebrado en Nantes (Francia) del 22 al 26 de mayo de 2016.The use of the effluent of wastewater treatment plants for the maintenance of wetlands is becoming a common practice in semiarid regions. We suggest that this type of ecosystem could act as an ecological trap, because it concentrates pathogenic organisms and a myriad of chemical pollutants coming from urban and industrial sources. Heavy metals have been reported as a cause of lethal poisoning and diverse sublethal effects by the impairment of biochemical processes.This study was supported by the Spanish Ministry of Environment (grant OAPN 755/2012). JJLP enjoys an FPU Predoctoral fellowship grant (ref. FPU12/04966) of the Spanish Ministry of Education.Peer Reviewe

Lead poisoning in waterbirds: Do limitations in the perception of risk reduce the compliance of Pb shot ban?

Resumen del trabajo presentado al 37th annual meeting of the Waterbird Society and the annual conference of the International Wader Study Group, celebrado en Wilhelmshaven (Alemania) del 24 al 30 de septiembre de 2013.Lead (Pb) has been an excellent material for hunting ammunition due to its high density and softness. Unfortunately, it is one of the most toxic heavy metals and spreading it in the environment makes hunting an unsustainable practice. The accumulation of spent Pb shot pellets is especially of concern in wetlands where waterbirds have been intensively hunted. High prevalence of Pb shot ingestion in waterbirds has been detected around the world and, in consequence, an increasing number of countries have adopted regulations to reduce the use of Pb shot in wetlands. However, the compliance of the ban of Pb shot differs among countries and it seems to be lower in Europe than in North America. In the Ebro delta (NE Spain), the prevalence of Pb shot ingestion in hunted waterfowl in the 1990s was as high as 30% in Mallard Anas platyrhynchos and 69% in Common Pochard Aythya ferina. Ten years after the implementation of the ban of Pb shot use over protected wetlands in Spain in 2001, these rates of Pb shot ingestion have declined to 15% and 35%, respectively. Ban compliance by 2008 in protected lagoons of the Ebro delta was high, with ≤2% of hunted birds with only embedded Pb shot. However, this ban was not implemented at feeding sites in rice fields, where the ducks are still shot with Pb during full moon nights. Game meat Pb levels in waterfowl that had ingested Pb shot and/or birds killed with Pb ammunition in the Ebro delta were above maximum residue levels according to EU regulation. Therefore, more strict compliance on the use of Pb shot and an enforcement of the ban compliance can reduce game meat Pb levels by both the decrease in Pb shot ingestion rates and Pb embedded ammunition in birds. Despite the extensive research performed on lead poisoning, further studies on sublethal and population effects in birds and game meat consumers may be needed to increase the perception of Pb-related risk among hunters to favour Pb shot ban compliance.Peer Reviewe