Genotoxicity of three biofuel candidates compared to reference fuels.

Global demand for alternative energy sources increases due to concerns regarding energy security and greenhouse gas emissions. However, little is known regarding the impacts of biofuels to the environment and human health even though the identification of such impacts is important to avoid biofuels leading to undesired effects. In this study mutagenicity and genotoxicity of the three biofuel candidates ethyl levulinate (EL), 2-methyltetrahydrofuran (2-MTHF) and 2-methylfuran (2-MF) were investigated in comparison to two petroleum-derived fuels and a biodiesel.

Water sources of plant uptake along a salt marsh flooding gradient.

Salt marsh plants are affected by regular tidal inundation exposing them to saline water as a potential water source. This study aimed at quantifying the water uptake of plants depending on their distance from the sea and exploring plant responses to changing inundation regimes. We used stable isotope ratios (δO) to determine the proportions of seawater and precipitation water used by three salt marsh species (Spartina anglica, Atriplex portulacoides and Elytrigia atherica) from a German North Sea coast salt marsh.

Effects of Inundation, Nutrient Availability and Plant Species Diversity on Fine Root Mass and Morphology Across a Saltmarsh Flooding Gradient.

Saltmarsh plants are exposed to multiple stresses including tidal inundation, salinity, wave action and sediment anoxia, which require specific root system adaptations to secure sufficient resource capture and firm anchorage in a temporary toxic environment. It is well known that many saltmarsh species develop large below-ground biomass (roots and rhizomes) but relations between fine roots, in particular, and the abiotic conditions in salt marshes are widely unknown. We studied fine root mass (<2 mm in diameter), fine root depth distribution and fine root morphology in three typical communities (-dominated pioneer zone, -dominated lower marsh, -dominated upper marsh) across elevational gradients in two tidal salt marshes of the German North Sea coast [a mostly sandy marsh on a barrier island (Spiekeroog), and a silty-clayey marsh on the mainland coast (Westerhever)].

A hierarchical testing strategy for micropollutants in drinking water regarding their potential endocrine-disrupting effects-towards health-related indicator values.

In Germany, micropollutants that (may) occur in drinking water are assessed by means of the health-related indicator value (HRIV concept), developed by the German Federal Environment Agency. This concept offers five threshold values (≤ 0.01 to ≤ 3 μg l) depending on availability and completeness of data regarding genotoxicity, neurotoxicity, and germ cell-damaging potential.

Bioaccumulation and molecular effects of sediment-bound metals in zebrafish embryos.

Predicting the bioavailability and effects of metals in sediments is of major concern in context with sediment risk assessment. This study aimed to investigate the bioavailability and molecular effects of metals spiked into riverine sediments to zebrafish (Danio rerio) embryos. Embryos were exposed to a natural and an artificial sediment spiked with cadmium (Cd), copper (Cu), nickel (Ni) and zinc (Zn) individually or as a mixture at concentrations ranging from 150 to 3000 mg/kg dry weight (dw) over 48 h, and uptake of metals was determined.