Heavy Metal Uptake and Toxicity in the Presence of Titanium Dioxide Nanoparticles: A Factorial Approach Using Daphnia magna.

Abstract

Unintentionally released titanium dioxide nanoparticles (nTiO2) may co-occur in aquatic environments together with other stressors, such as, metal ions. The effects of P25-nTiO2 on the toxicity and uptake of the elements silver (Ag), arsenic (As) and copper (Cu) were assessed by applying a factorial test design. The test design consisted of two developmental stages of Daphnia magna, two levels of nTiO2 (0 versus 2 mg/L) as well as seven nominal test concentrations of the respective element. The presence of nTiO2 increased Ag toxicity for juveniles as indicated by a 40% lower 72-h EC50, while the toxicities of As and Cu were reduced by up to 80%. This reduction was even more pronounced for Cu in the presence of dissolved organic carbon (i.e., seaweed extract) and nTiO2. This outcome coincides with the body burden of the elements, which was elevated 2-fold for Ag and decreased 14-fold for Cu in the presence of nTiO2. Although the underlying mechanisms could not be uncovered, the data suggest that the carrier function of nTiO2 plays a central role. However, to understand the processes and mechanisms occurring in the field due to the presence of nTiO2 further systematic investigations considering environmental variables and nanoparticle characteristics are required.

The impact of TiO2 nanoparticles on uptake and toxicity of benzo(a)pyrene in the blue mussel (Mytilus edulis)

“…ENPs also appear to affect the uptake of metals and chemical elements in aquatic organisms. In D. magna, co-exposure to TiO2NP enhanced the uptake of Ag and As, but reduced the uptake of Cu by a factor of 14 (Rosenfeldt et al, 2014). Furthermore, higher accumulation of As and Cd was reported in carp (Cyprinus carpio) when exposed in combination with TiO2NP Zhang et al, 2007).…”

The relative importance of diet-related and waterborne effects of copper for a leaf-shredding invertebrate

“…Cu concentrations were measured in fresh and 3-day-old (i.e., before medium renewal) conditioning and bioassay medium (n ¼ 4) using inductively coupled plasma quadrupole mass spectrometry (Rosenfeldt et al, 2014). Results of the measurements justified an accurate Cu dosage (deviation from nominal 7%; Table 1).…”

Acute toxicity of benzophenone-type UV filters for Photobacterium phosphoreum and Daphnia magna: QSAR analysis, interspecies relationship and integrated assessment

“…Biotests with P. phosphoreum have successfully been used to investigate the toxicities of various inorganic and organic compounds in water samples Zou et al, 2012;Ge et al, 2014a,b;Wang et al, 2014a,b,c). Similarly, Daphnia magna (D. magna) is an important freshwater invertebrate species in aquatic food webs and has been used world-wide as a standard testing organism for the study of the toxicities of pollutants (De Coninck et al, 2014;Rosenfeldt et al, 2014;Roy et al, 2014). Knowledge of the physico-chemical properties, fate, and eco-toxicological effects is fundamental for preliminary assessments (at least the ''base set'' of data; i.e., the EC 50s for bacterium, algae, crustaceans and fish) of the effects of pollutants (Zhang et al, 2013a,b,c;Minguez et al, 2014;Wang et al, 2014a,b,c).…”