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We studied perfluorooctane sulfonate (PFOS) levels in the eggs of three primarily invertivorous bird species sampled in 2006 near a fluoro-chemical plant: the great tit (Parus major), the northern lapwing (Vanellus vanellus) and the Mediterranean gull (Larus melanocephalus). Our study reported some of the highest PFOS levels ever measured in wildlife to date (i.e. up to 46182ng/g ww in lapwing eggs). A pronounced decrease in PFOS concentration in the Northern lapwing eggs with distance from the fluoro-chemical plant was found. A similar relationship was found for the great tit, with eggs being collected close to the fluoro-chemical plant having significantly higher PFOS levels than eggs collected 1700m further away. When comparing the PFOS levels in eggs for the three species, collected between 1700 and 5500m no significant differences were observed. In addition, when comparing PFOS levels in eggs between Northern lapwing and great tits closer to the plant (900-1700m) no significant differences were found neither. Despite the high levels found in great tit eggs, plasmatic biochemical biomarker responses did not appear to be affected.

Perfluorooctane sulfonate (PFOS) and other perfluoroalkyl compounds (PFCs) were measured in liver samples from 29 marine tucuxi dolphins from Rio de Janeiro state (RJ), Brazil. PFC measurement combined liquid chromatography and mass spectrometry, using a CapLC system connected to a Quadrupole-LIT mass spectrometer. PFOS was the only PFC detected and it was so in all samples. PFOS concentrations (ng · g -1 dw) of dolphins (n ) 23) from the highly contaminated Guanabara Bay (in RJ) varied between 43 and 2431 as well as between 76 and 427 from areas of RJ other than the quoted bay (n ) 6). Concentrations of three fetuses and one neonate varied between 664 and 1590. Fetus/mother ratios were calculated in two situations (2.75 and 2.62). It seems that mother-to-calf transference plays important role for relationships between PFOS and age. When a one-year-old male calf presenting 2431 ng · g -1 dw was excluded from the test, significant correlations were observed between PFOS concentrations and both age and total length. Despite the placental transference, PFOS concentrations were not significantly lower in females than in males. PFOS levels in marine tucuxi dolphins from Guanabara Bay are among the highest detected to date in cetaceans, and this may represent a threat to the small population concerned.

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The aim of this study was to evaluate the occurrence of five perfluorinated chemicals (perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorohexane sulfonic acid (PFHxS), and perfluorobutane sulfonic acid) in aquatic organisms dwelling in either freshwater or marine ecosystems. Organisms selected were insect larvae, oysters, zebra mussels, sardines, and crabs, which are widespread in the environment and may represent potential bioindicators of exposure to PFCs. The study comprises the optimization of a solid-liquid extraction method and determination by high-performance liquid chromatography coupled to tandem mass spectrometry. Using spiked zebra mussels at 10 and 100 ng/g level, the method developed provided recoveries of 96% and 122%, and 82% to 116%, respectively, and a limit of detection between 0.07 and 0.22 ng/g ww. The method was highly sensitivity and robust to determine PFC compounds in a wide array of biological matrices, and no matrix interferents nor blank contamination was observed. Among organisms studied, none of the bivalves accumulated PFCs, and contrarily, insect larvae, followed by fish and crabs contained levels ranging from 0.23 to 144 ng/g ww of PFOS, from 0.14 to 4.3 ng/g ww of PFOA, and traces of PFNA and PFHxS. Assessment of the potential use of aquatic organisms for biomonitoring studies is further discussed.

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The arena of Unmanned Aerial Vehicles (UAVs) has for many years been dominated by the defence industries. The reason for this can be attributed to the complexity and cost of designing, constructing and operating of these vehicles. An additional contributing factor is the legislative issues around operating an unmanned aircraft in civilian airspace. However in resent years advances in micro-electronics especially Micro Electronic Mechanical Systems (MEMS) and advanced composite manufacturing techniques have placed the design and construction of UAVs in the domain of the commercial civilian users. A number of commercial UAV applications have emerged where the legislative requirements for operating of a UAV in segregated airspace can be met. UAVs are extremely well suited for the dull, dirty and dangerous tasks encountered in performing surveying and surveillance applications. For these tasks the primary design considerations in the design of the UAV would be the propulsion system, the guidance and control system and the payload system. IntroductionThe European Unmanned Vehicle Association identifies five main categories of UAVs (Sarris, 2001):• Close range -fly in a range of less than 25 km. Usually extremely light;• Short range -operate within a range of 25-100km.• Medium range -Able to fly within a range of 100-200km. Need more advanced aerodynamic design and control systems due to their higher operational performance.• Long range -Fly within a range of 200-500km. Require more advanced technology to carry out complex missions. Need satellite link in order to overcome the communication problem between the ground control systems and aircraft created by the curvature of the earth.• Endurance -Operate in a range more than 500km, or can stay in the air for more than 20 hrs. This is considered the most sophisticated of the UAV family due to their high capabilities. This chapter presents design considerations for UAVs which can be categorized as endurance UAVs. The design considerations discussed include the primary UAV systems namely, propulsion system, navigation and control system and sensor payload system.