Granulometry and the content of toxic and potentially toxic elements in vacuum-cleaner collected, indoor dusts of the city of Warsaw.

Twenty-seven sites, together with 23 household dust sample sites, representing the home environment, and four public room dust sample sites, representing working environment (mainly offices) have been described in this paper. The latter were examined to obtain an approximate reference to the home environment data. All the samples were collected between May and July 1997 by a vacuum-cleaner method, in the city of Warsaw, Poland.

Localization of lead in Allium cepa L. cells by electron microscopy.

The study of mechanisms by which plants tolerate lead requires ultrastructural observations of lead distribution in cells. However, the conventional technique used in electron microscopy brings up the problem of lead translocation from tissues during chemical processing. If most of the lead is washed out of tissues, then the method is not suitable for this type of study; if, however, it remains in the tissues, the method can be used.

Reinvestigation of apple-seed gibberellins.

Re-investigation of the gibberellins in apple seed has established the presence of GA4 and GA7 and of traces of GA9. The fraction, previously considered to be GA7 by TLC, contains small amounts of GA4 and traces of GA9; and the fraction, characterized as GA4 by TLC, contains traces of GA7 and GA9. However the present results do not change the previous conclusions that during the stratification of apple seed the level of GA7 remains fairly constant while that of GA4 increases.