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In the present thesis, analytical methods based on gas chromatography coupled with mass spectrometry, both single (GC-MS) or tandem (GC-MS/MS), have been developed and optimized for the detection and quantification of persistent organic pollutants (POPs) such as organochlorinated pesticides (OCPs) and polychlorinated byphenils (PCBs) and emerging pollutants such as organophosphate esters (OPEs), which are currently used as flame retardants, additives and plasticizers. Another family of flame retardants, also classified as POPs, polybrominated diphenil ethers (PBDEs), was also studied and quantified using already optimized and validated methods. The presence of target POPs in environmentally protected areas of the Iberian Peninsula has been evaluated using seagull eggs as bioindicators. Two species, namely yellow-legged gull (Larus michahellis) and Audouin´s gull (Larus Audouinii), have been selected for this purpose. The former is an abundant and widely distributed species with scavenging and opportunistic behavior, while the later is more vulnerable, even though the population is growing during recent years and new colonies are emerging, and showed a strict fish-based diet. Pollution levels detected in gull eggs were dominated by PCBs, followed by various OCPs. Among OCPs, high levels of dichlorodiphenyldichloroethylene (DDE) were found, which is a metabolic and degradation product of dichlorodiphenyltrichloroethane (DDT), a pesticide widely used during the last decades of the 20th century, which showed high toxicity for birds, being able to reduce the reproduction success because it may affect the eggshell thickness and prevent hatching when present at high enough levels. PBDEs were also widespread in the marine environments of the Iberian Peninsula but at lower levels. Audouin´s gull eggs showed higher pollution levels than yellow-legged gulls from the same colonies, suggesting differences in their feeding habits and their bioaccumulation capacity of POPs. In gen, En la presente tesis doctoral se ha estudiado la presencia y distribución de pesticidas organoclorados y retardantes de llama en áreas ambientalmente protegidas de España y China y en una zona afectada por residuos electrónicos en China. Para ello se han desarrollado y aplicado métodos multiresiduo basados en cromatografía de gases acoplada a espectrometría de masas, tanto simple como en tándem, para la detección y cuantificación de, por un lado, contaminantes cuyo uso ha sido restringido y prohibido bajo las directrices del Convenio de Estocolmo y conocidos por sus características fisicoquímicas como compuestos orgánicos persistentes (COPs), los cuales incluyen pesticidas organoclorados (OCPs por sus siglas en inglés), bifenilos policlorados (PCBs) y polibromodifenil éteres (PBDEs) y, por otro lado, una familia de contaminantes emergentes utilizados como plastificantes, aditivos y retardantes de llama como son los ésteres organofosforados (OPEs). En España, el estudio de COPs se ha llevado a cabo mediante el uso de huevos de gaviota como bioindicadores de la contaminación ambiental y se han evaluado los niveles de estos compuestos antropogénicos en las mayores colonias de gaviotas de la península Ibérica, constituidas en zonas con diferentes grados de protección ambiental. Los compuestos detectados a mayor nivel fueron los OCPs, y más en concreto el dicloro difenil tricloroetano (DDT) y sus productos de degradación, seguidos por los PCBs y a menores niveles los PBDEs. En China, se ha detectado la presencia tanto de COPs como de OPEs en suelos y sedimentos de zonas protegidas como parques nacionales y/o reservas naturales que, en principio, deberían ser prístinas. Los contaminantes detectados a mayores niveles fueron los OPEs, probablemente debido a su uso actual. Sin embargo, el isómero alfa del hexaclorociclohexano, así como el PBDE 209 demostraron ser ubicuos en el medio ambiente, lo cual concuerda con los grandes volúmenes de producción y consumo de los mismos e

Bio-based materials are showing great potential to be widely used in construction industry, while reducing fire risk and improving fire resistance of these alternatives also become a major concern due to their inherent flammability. Initially, this review introduces three common bio-based construction materials, including biopolymer-based materials, wood-based materials, and crop-based materials, and their fire behaviors in flaming and smoldering combustion scenarios, accompanied with some typical flame-retardant mechanisms. Sequentially, the recent achievements in improving fire resistance are mainly exhibited in detail for each kind of bio-based materials. There are numerous reports for biopolymer-based flame-retardant materials with mature flame-retardant methodology. With regard to wood-based flame-retardant materials, different criteria and methodologies are needed to evaluate the flame-retardant properties. Meanwhile, in the case of crop-based insulation materials is essential to carefully consider the fire behavior, both in flaming and smoldering combustions, and not only focus on their thermal performance. In the final section, based on the requirements of fire safety and practicality for construction materials, bio-based alternatives with excellent good fire resistance and practical performance are summarized to be a promising way to meet future challenges, Peer Reviewed, Postprint (author's final draft)

In the present thesis, analytical methods based on gas chromatography coupled with mass spectrometry, both single (GC-MS) or tandem (GC-MS/MS), have been developed and optimized for the detection and quantification of persistent organic pollutants (POPs) such as organochlorinated pesticides (OCPs) and polychlorinated byphenils (PCBs) and emerging pollutants such as organophosphate esters (OPEs), which are currently used as flame retardants, additives and plasticizers. Another family of flame retardants, also classified as POPs, polybrominated diphenil ethers (PBDEs), was also studied and quantified using already optimized and validated methods. The presence of target POPs in environmentally protected areas of the Iberian Peninsula has been evaluated using seagull eggs as bioindicators. Two species, namely yellow-legged gull (Larus michahellis) and Audouin´s gull (Larus Audouinii), have been selected for this purpose. The former is an abundant and widely distributed species with scavenging and opportunistic behavior, while the later is more vulnerable, even though the population is growing during recent years and new colonies are emerging, and showed a strict fish-based diet. Pollution levels detected in gull eggs were dominated by PCBs, followed by various OCPs. Among OCPs, high levels of dichlorodiphenyldichloroethylene (DDE) were found, which is a metabolic and degradation product of dichlorodiphenyltrichloroethane (DDT), a pesticide widely used during the last decades of the 20th century, which showed high toxicity for birds, being able to reduce the reproduction success because it may affect the eggshell thickness and prevent hatching when present at high enough levels. PBDEs were also widespread in the marine environments of the Iberian Peninsula but at lower levels. Audouin´s gull eggs showed higher pollution levels than yellow-legged gulls from the same colonies, suggesting differences in their feeding habits and their bioaccumulation capacity of POPs. In gen, En la presente tesis doctoral se ha estudiado la presencia y distribución de pesticidas organoclorados y retardantes de llama en áreas ambientalmente protegidas de España y China y en una zona afectada por residuos electrónicos en China. Para ello se han desarrollado y aplicado métodos multiresiduo basados en cromatografía de gases acoplada a espectrometría de masas, tanto simple como en tándem, para la detección y cuantificación de, por un lado, contaminantes cuyo uso ha sido restringido y prohibido bajo las directrices del Convenio de Estocolmo y conocidos por sus características fisicoquímicas como compuestos orgánicos persistentes (COPs), los cuales incluyen pesticidas organoclorados (OCPs por sus siglas en inglés), bifenilos policlorados (PCBs) y polibromodifenil éteres (PBDEs) y, por otro lado, una familia de contaminantes emergentes utilizados como plastificantes, aditivos y retardantes de llama como son los ésteres organofosforados (OPEs). En España, el estudio de COPs se ha llevado a cabo mediante el uso de huevos de gaviota como bioindicadores de la contaminación ambiental y se han evaluado los niveles de estos compuestos antropogénicos en las mayores colonias de gaviotas de la península Ibérica, constituidas en zonas con diferentes grados de protección ambiental. Los compuestos detectados a mayor nivel fueron los OCPs, y más en concreto el dicloro difenil tricloroetano (DDT) y sus productos de degradación, seguidos por los PCBs y a menores niveles los PBDEs. En China, se ha detectado la presencia tanto de COPs como de OPEs en suelos y sedimentos de zonas protegidas como parques nacionales y/o reservas naturales que, en principio, deberían ser prístinas. Los contaminantes detectados a mayores niveles fueron los OPEs, probablemente debido a su uso actual. Sin embargo, el isómero alfa del hexaclorociclohexano, así como el PBDE 209 demostraron ser ubicuos en el medio ambiente, lo cual concuerda con los grandes volúmenes de producción y consumo de los mismos e