Mercury Isotope Variability in Pyrenean Lake Sediments during the Late Holocene: Sources, Deposition, and Environmental Controls.

Atmospheric mercury (Hg) emissions represent a persistent global threat to ecosystems and human health. Stable Hg isotopes have emerged as powerful tools to trace historical pollution sources and reconstruct depositional pathways in natural archives. In this study, we present a 4000-year reconstruction of Hg isotopic composition from two Pyrenean lake sediment records (Lake Marboré and Lake Estanya) located along an altitudinal gradient and compare them with those of a nearby ombrotrophic peatland (Estibere mire).

Factors influencing the cleaning of plant samples with ultrasonic technology.

Effective cleaning of biological samples is a critical step in environmental studies. However, the literature lacks standardized cleaning procedures and protocols and there is little information about how even the most basic conditions may affect cleaning efficiency. Here, leaves of different species were first exposed to the soil naturally containing mercury particles and then washed in an ultrasound water bath under the following conditions: newly cleaned/reused beakers, water temperature, sample immersion/free-floating, sample quantity, and the number of washing cycles.

Effects of mercury on the germination and growth of Quercus ilex L. seedlings.

While it is well-known that the toxicity of mercury for plants is related to its bioavailability in the environment in which the plant lives, few studies have addressed Hg effects under controlled conditions of life-limiting available Hg concentrations. This study examines the effects of Hg on the holm oak (Quercus ilex L.) exposed to medium-high available Hg concentrations.

Homocysteine is a potent modulator of plasma membrane electron transport systems.

The deregulation of homocysteine metabolism leads to hyperhomocysteinemia, a condition described as an independent cardiovascular disease risk factor. Ubiquitous plasma membrane redox systems can play a dual pro-oxidant and anti-oxidant role in defense. In this study, we test the hypothesis that homocysteine, as a redox active compound, could modulate the endothelial plasma membrane redox system.