Pharmacokinetics of repeated sodium salicylate administration to laying hens: evidence for time dependent increase in drug elimination from plasma and eggs.

Salicylates were the first non-steroid anti-inflammatory drugs (NSAIDs) to be used in any species and are still widely used in humans and livestock. However, the data on their pharmacokinetics in animals is limited, especially after repeated administration. Evidence exist that in chickens (Gallus gallus) salicylate (SA) may induce its own elimination. The aim of this study was to investigate salicylate pharmacokinetics and egg residues during repeated administration of sodium salicylate (SS) to laying hens. Pharmacokinetics of SA was assessed during 14 d oral administration of SS at daily doses of 50 mg/kg and 200 mg/kg body weight to laying hens. On the 1st, 7th and 14th d a 24 h-long pharmacokinetic study was carried out, whereas eggs were collected daily. Salicylate concentrations in plasma and eggs were determined using high-performance liquid chromatography with ultraviolet detection and pharmacokinetic variables were calculated using a non-compartmental model. Mean residence time (MRT), minimal plasma concentration (Cmin, C16h) and elimination half-life (T1/2el) of SA showed gradual decrease in layers administered with a lower dose. Total body clearance (ClB) increased. Layers administered with the higher dose showed a decrease only in the T1/2el. In the low dose group, SA was found only in the egg white and was low throughout the experiment. Egg whites from the higher dose group showed initially high SA levels which significantly decreased during the experiment. Yolk SA levels were lower and showed longer periods of accumulation and elimination. Repeated administration of SS induces SA elimination, although this effect may differ depending on the dose and production type of a chicken. Decreased plasma drug concentration may have clinical implications during prolonged SS treatment

Best practices in monitoring

This chapter summarizes the methods used within the MODUM project for monitoring chemical munition dumpsites. It includes general introduction to monitoring process, listing the requirements that are a basis for the establishment of full scale monitoring programme. It describes survey procedures, for locating dumped munitions, Sampling and analytical procedures for the detection of Chemical Warfare Agents, as well as the usage of fish as bioindicators are described. Modelling of pollutants originating from dumped munitions is presented and discussed. Only methods, which were proven to be most effective within the MODUM projects were selected, also data interpretation methods providing coherent information regarding the environmental risk are explained in details

Plasma salicylate (SA) concentration time curves as determined on days 1, 7 and 14.

<p>Laying hens were treated daily with sodium salicylate (SS) at an oral dose of 50 mg/kg (upper panel) or 200 mg/kg (lower panel) for two weeks.</p

Time-dependent changes in egg white and yolk salicylate (SA) concentrations in the higher dose group (200 mg/kg).

<p>Letter (A) indicates the onset of daily sodium salicylate (SS) administration and letter (B) points the last SS dose.</p

Salicylate (SA) concentrations in egg white of eggs collected from day 2 to 14.

<p>To show the relation with blood SA levels, plasma drug concentration at 16 h post administration (C_16h) is included. Linear regression analysis was performed to investigate the statistical significance of the time-dependent changes in egg white SA.</p

Chemical munitions search and assessment - an evaluation of the dumped munitions problem in the Baltic Sea

Chemical Munitions Search & Assessment (CHEMSEA) project has performed studies on chemical weapon (CW) detection, sediment pollution and spreading as well as biological effects of chemical warfare agents (CWAs) dumped in the Baltic Sea. Results suggest that munitions containing CWAs are more scattered on the sea floor than suspected, and previously undocumented dumpsite was discovered in Gdansk Deep. Pollution of sediments with CWA degradation products was local and close to the detected objects; however the pollution range was larger than predicted with theoretical models. Bottom currents observed in the dumpsites were strong enough for sediment re-suspension, and contributed to the transport of polluted sediments. Diversity and density of the faunal communities were poor at the dumping sites in comparison to the reference area, although the direct effects of CWA on benthos organisms were difficult to determine due to hypoxic or even anoxic conditions near the bottom. Equally, the low oxygen might have affected the biological effects assessed in cod and caged blue mussels. Nonetheless, both species showed significantly elevated molecular and cellular level responses at contaminated sites compared to reference sites