Experimental evidence for clothianidin deposition in feathers of house sparrows after ingestion of sublethal doses treated seeds.

Bird feathers are commonly used to assess environmental contamination by chemical pollutants. However, although neonicotinoid insecticides are widely applied worldwide, feathers have rarely been used to survey the contamination by neonicotinoids in birds. To investigate whether clothianidin, one compound of the neonicotinoid class, is deposited into birds' feathers, we conducted an experiment with 56 wild male and female house sparrows dispatched in 7 aviaries. During this experiment, house sparrows were fed with certified organic seeds treated with clothianidin at an estimated concentration of 0.25 µg/g BW per day and per individual. We collected blood samples and plucked four tail feathers at the onset of the experiment to confirm that no birds were previously exposed to clothianidin. 35 days later, we collected blood samples and the newly grown feathers. Before exposure, a small number of birds showed very low clothianidin concentrations in plasma and feathers. After exposure, the plasma and the newly grown feathers of all birds contained clothianidin. Clothianidin concentrations in feathers were similar in both sexes, but the plasma of males contained clothianidin at higher concentrations than that of females. Our results confirm that ingested clothianidin transits in the plasma and is deposited in feathers during their growth. They also suggest substantial individual variation in the amounts of clothianidin transiting in the plasma and being deposited in feathers that may reflect variation in metabolism and/or access to food in relation to sex, social hierarchy and group dynamics. Whether increasing levels of exposure translate linearly or non-linearly (e.g. saturation process) into increasing clothianidin concentrations in bird plasma and feathers remains to be investigated. To conclude, these results confirm the relevance of using feathers to biomonitor the presence of neonicotinoids, but the relationship between the level of exposure and the concentrations found in feathers remains to be established.

International multicentre study of indapamide in the treatment of essential arterial hypertension.

A total of 1600 patients with essential arterial hypertension was recruited from 10 countries, and treated with indapamide according to a common protocol. 703 subjects who completed the protocol were analysed, from whom 644 were followed for 3 months, and the remainder (all from Belgium) up to 10 months. The group of 644 showed a highly significant drop in erect and supine blood pressures after one month, and this was maintained after 3 months treatment. The percentage of responders (normalization of diastolic pressure, or drop of at least 30 mmHg) was 64% after 3 months. The Belgian group maintained their reductions in pressure at 6 and 10 months. Serum potassium showed a modest drop, but remained within normal limits: other biochemical values were virtually unchanged. Some side effects were noted, but none was serious. It is concluded that indapamide is a first line treatment for essential arterial hypertension.