Ecotoxicological diagnosis of a sealed municipal landfill.

Assessing the environmental impact of a soil-topped landfill requires an accurate ecotoxicological diagnosis. This paper describes various diagnostic protocols for this purpose and their application to a real case: the urban solid waste (USW) municipal landfill of Getafe (Madrid, Spain). After their initial sealing with soil from the surroundings about 20 years ago, most USW landfills in the autonomous community of Madrid have continued to receive waste. This has hindered precise assessment of their impact on their environment and affected ecosystems. The procedure proposed here overcomes this problem by assessing the situation in edaphic, aquatic and ecological terms. The present study focused on the most influential soil variables (viz. salinity due largely to the presence of anions, and heavy metals and organic compounds). These variables were also determined in surface waters of the wetland most strongly affected by leachates running down landfill slopes. Determinations included the characterization of plant communities and microbial biodiversity. The study was supplemented with a bioassay under controlled conditions in pots containing soil contaminated with variable concentrations of Zn (as ZnCl(2)) intended to assess ecochemical actions in a population of Bromus rubens, which grows profusely in the landfill.

Two new sulfated saponins from the roots of Gypsophila bermejoi.

Two new sulfated saponins (1 and 2) were isolated from a butanol-soluble extract of the roots of Gypsophila bermejoi and were identified by a combination of chemical degradation and spectral methods as the 3beta-sulfate ester of gypsogenin 28-O-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->6)]-beta -D-glucopyranoside (1), and the 23-sulfate ester of hederagenin 28-O-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->6)]-beta -D-glucopyranoside (2), respectively. Plants of the genus Gypsophila (Caryophyllaceae) are important industrially because of the capacity of their saponin constituents to behave like natural detergents.1 Saponins from this genus are based on oleanolic acid (3-hydroxyolean-12-en-28-oic acid), with gypsogenin being the main pentacyclic triterpenoidal aglycon found. In general, this aglycon is substituted at the C-3 hydroxyl and/or C-28 carboxylic acid groups by saccharide units.2