Varying chick mortality in an organochlorine-"strained" population of the nominate lesser black-backed gull Larus f. fuscus in the Baltic Sea

Severe reproductive failure has contributed to a drastic population decline of the nomi-nate Lesser Black-backed Gull (Larus fuscus fuscus) in its breeding grounds in the Gulf of Finland and the Bay of Bothnia. In intensive field studies in the central area of the Gulf of Finland, roughly 65–70 % of chicks died in their nest in the 1980s and 1990s due to innate diseases. In the 1990s, the fledging rate was only 0.02. The diseases consisted mainly of liver degeneration and various inflammations, and most chicks died of sepsis. The hepatic concentrations of legacy organochlorines (OC) in dead chicks were high, and they corre-lated with the proportion of dead chicks in a brood. During the 2000s, however, the occur-rence of diseased chicks in the Gulf of Finland decreased to 48%, which helped to achieve a fledging rate supposedly sustaining the population (0.52). At the same time, the trends in hepatic levels of certain legacy OCs in chicks decreased, especially the DDE, HCB, -HCH, and trans-nonachlor levels. In spite of skewed sampling (only dead chicks were available), our results indicate an enhancing health status among the present population, probably due to a less contaminated diet during the non-breeding period

Proficiency Test SYKE 8/2012. Volatile organic compounds in water and soil

Proftest SYKE carried out the proficiency test for analysis of volatile organic compounds from water and soil in October 2012. One artificial sample and one river water sample and one soil sample were distributed. In total, 15 laboratories participated in the proficiency test. Either the calculated concentration or the robust mean value was chosen to be the assigned value for the measurement. The performance of the participants was evaluated by using z scores. In this proficiency test 72 % of the results were satisfactory when the deviation of 15–40 % from the assigned value was accepted

Proficiency Test SYKE 9/2012. Oil hydrocarbons in water and soil

Proftest SYKE carried out the proficiency test for analysis of oil hydrocarbons from water and soil in October 2012. One artificial sample and one surface water sample and one soil sample for the determination of oil hydrocarbons were distributed. In total, 18 laboratories participated in the PT. Either the calculated concentration or the robust mean value was chosen to be the assigned value for the measurement. The performance of the participants was evaluated by using z scores. In this proficiency test 81 % of the results were satisfactory when the deviation of 20–40 % from the assigned value was accepted