Meat quality in relation to swine well-being after transport and during lairage at the slaughterhouse.

Cortisol and corticosterone in saliva were evaluated as pig stress biomarkers, using pig genotype (Duroc, L62 or Pietrain) and lairage time in the slaughterhouse (0, 2.0, 4.0 or 6.0 h) as controlled variables. Although some pigs were found to be carriers of stress susceptibility, all were healthy heterozygous individuals. Pre-slaughter transport increased cortisol levels in saliva above 3.0 µg/L (medium stress), and 4.0 h of lairage in the slaughterhouse raised them above 6.0 µg/L, whereas corticosterone concentrations exceeded 4 µg/L, which are suggestive of high stress. The highest cortisol levels were detected in the Duroc genotype. Other factors such as food deprivation, background noise, the presence of a large number of animals waiting to be slaughtered, mixing with unfamiliar animals or recent mixing of genders may also influence stress. Corticosterone proved a reliable indicator of high stress only. Meat quality from the pig breeds studied was not affected by lairage in the slaughterhouse for up to 6.0 h.

Ultrasound-assisted emulsification-microextraction for the determination of phenolic compounds in olive oils.

A reliable, sensitive and effective method based on ultrasound-assisted emulsification-microextraction (USAEME) coupled to HPLC-DAD has been developed to identify and quantify several target phenolic compounds from extra virgin olive oils (EVOO). This approach is based on the emulsification of a microvolume of polar organic extractant in a non-polar liquid sample by ultrasound radiation and further separation of both liquid phases by centrifugation. The percentage of methanol/water (v/v) in the extractant, the volume of extractant, and the extraction time as three effective parameters on the extraction were optimised by a central composite design (Box-Behnken response surface) method. The optimised method presented recoveries in EVOO between 91% and 115% for the target analytes (except vanillin with 65%) and a satisfactory precision with relative standard deviations (RSD%) lower than 8.4% for repeatability and reproducibility. The method showed good linearity and limits of detection and quantification were in the range 0.001-0.14 and 0.004-0.47mg/kg, respectively. After method validation, it was successfully applied to the analysis of three EVOO samples. All target compounds were detected in all analysed samples. Tyrosol and hydroxytyrosol were the major phenolic compounds, followed by pinoresinol and luteolin.

Simulation of a Hazardous and Noxious Substances (HNS) spill in the marine environment: lethal and sublethal effects of acrylonitrile to the European seabass.

Despite the extensive maritime transportation of Hazardous and Noxious Substances (HNS), there is a current lack of knowledge on the effects posed by HNS spills on the marine biota. Among the HNS identified as priority, acrylonitrile was selected to conduct ecotoxicological assays. We assessed the acute and subletal effects of acrylonitrile in seabass, followed by a recovery phase to simulate the conditions of a spill incident. The work aimed at testing a broad range of biological responses induced by acrylonitrile. Sublethal exposure to the highest two doses increased the fish mortality rate (8.3% and 25% mortality in 0.75 and 2 mg L(-1) acrylonitrile concentrations), whereas no mortality were observed in control and 0.15 mg L(-1) treatments. Additionally, important alterations at sub-individual level were observed. Acrylonitrile significantly induced the activities of Catalase- CAT and Glutathione S-Transferase - GST; and the levels of DNA damage were significantly increased. Conversely, Superoxide Dismutase- SOD - activity was found to be significantly inhibited and no effects were found on Lipid Peroxidation- LPO and ethoxyresorufin O-deethylase - EROD - activity. Following a 7d recovery period, the levels of CAT, GST and EROD fell to levels at or below those in the control. In the 2 mg L(-1) group, SOD remained at the levels found during exposure phase. This study has gathered essential information on the acute and subletal toxicity of acrylonitrile to seabass. It also demonstrated that 7d recovery allowed a return of most endpoints to background levels. These data will be useful to assist relevant bodies in preparedness and response to HNS spills.

Procedure to measure the level of polycyclic aromatic hydrocarbons in wood ashes used as fertilizer in agroforestry soils and their transfer from ashes to water.

Before wood ash can be safely used as a fertilizer in soils, possible negative effects such as input of organic contaminants or remobilization of contaminants already stored in the soil must be investigated. The objective of this study was to optimize and characterize extraction methods to isolate and quantitatively measure polycyclic aromatic hydrocarbons (PAHs) concentrations in wood ash that can be used as amendment of soils. It will be then possible to examine the effects of wood ash application on PAHs concentrations in the washing waters with the aim of evaluating their distribution by storage in the different compartments and what influences their stability and persistence. Simple, rapid and inexpensive methods have been set up for the determination of seven polycyclic aromatic hydrocarbons (PAHs) in wood ashes and ash aqueous extracts without interferences from other chemical contaminants using organic solvent extraction and/or SPE techniques and analyzed by an optimized RP-HPLC-FLD method. The feasibility of extraction for the determination of PAHs in wood ashes has been evaluated because PAHs are strongly sorbed to such a matrix, which explains why the PAHs content in ash was seldom studied. The method resulted to be of recoveries ranging from 81 to 97% for the different PAHs, with repeatabilities (RSDs%) better than 6%. Detection levels were from 0.2 to 2.2 microg/kg, while quantification limits were from 0.7 to 5.6 microg/kg, low enough to evaluate the presence of PAHs in wood ashes.