Influence of Humic Acid on Titanium Dioxide Nanoparticle Toxicity to Developing Zebrafish
- Authors
- Yang, S., Bar-Ilan, O., Peterson, R.E., Heideman, W., Hamers, R.J., and Pedersen, J.A.
- ID
- ZDB-PUB-130201-12
- Date
- 2013
- Source
- Environmental science & technology 47(9): 4718-4725 (Journal)
- Registered Authors
- Heideman, Warren, Peterson, Richard E.
- Keywords
- none
- MeSH Terms
-
- Animals
- Environment
- Humic Substances*
- Metal Nanoparticles/toxicity*
- Titanium/toxicity*
- Zebrafish
- PubMed
- 23347333 Full text @ Env. Sci. Tech.
Titanium dioxide nanoparticle (TiO2NP) suspension stability can be altered by adsorption of dissolved organic matter (DOM). This is expected to impact their environmental fate and bioavailability. To date, the influence of DOM on the toxicity of TiO2NPs to aquatic vertebrates has not been reported. We examined the impact of Suwannee River humic acid (HA) on the toxicity of TiO2NPs to developing zebrafish (Danio rerio) in the presence and absence of simulated sunlight. Adsorption of HA increased suspension stability and decreased TiO2NP exposure. In the absence of simulated sunlight, a small increase in lethality was observed in fish exposed to TiO2NPs in the presence of HA. Under simulated sunlight illumination, photocatalytic degradation of HA reduced suspension stability. Despite the lower concentrations of Ti associated with fish in the treatments containing HA, under simulated sunlight illumination median lethal concentrations were lower and oxidative DNA damage was higher relative to fish exposed to TiO2NPs in the absence of HA. TiO2NPs were more toxicity in the presence of HA. This study demonstrates the importance of considering environmental factors (i.e., exposure to sunlight, adsorption of DOM) when assessing the risks posed by engineered nanomaterials in the environment.