The influence of hydroxyl-functionalized multi-walled carbon nanotubes and pH levels on the toxicity of lead to Daphnia magna

Environ Toxicol Pharmacol. 2014 Jul;38(1):199-204. doi: 10.1016/j.etap.2014.05.016. Epub 2014 Jun 8.

Abstract

The acute toxicity of lead was examined for Daphnia magna in waters with different pH values (5.0, 6.0, 7.0, 8.0 and 9.0) and different concentrations (0.01, 0.10, 0.50 and 1.00 mg/L) of hydroxyl-functionalized multi-walled carbon nanotubes (OH-MWCNTs). The results indicated that pH values could affect the toxicity of lead. With pH values increasing from 5.0 to 9.0, the 24h-LC₅₀ of Pb(II) increased from 0.784 to 9.473 mg/L, suggesting that the toxicity of Pb(II) was dramatically decreased. Although OH-MWCNTs almost caused no lethal effect to D. magna at the studied four concentrations, the combination of OH-MWCNTs and Pb(II) could cause more serious toxic effects to D. magna than Pb(II) alone. This study indicated that the synergistic effect caused by CNTs and lead could not be neglected.

Keywords: Acute toxicity; Daphnia magna; Hydroxyl-functionalized multi-walled carbon nanotubes; Lead; pH values.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Daphnia / drug effects*
  • Drug Synergism
  • Hydrogen-Ion Concentration
  • Hydroxyl Radical / chemistry*
  • Lead / toxicity*
  • Lethal Dose 50
  • Nanotubes, Carbon / chemistry
  • Nanotubes, Carbon / toxicity*
  • Water Pollutants, Chemical / toxicity*

Substances

  • Nanotubes, Carbon
  • Water Pollutants, Chemical
  • Lead
  • Hydroxyl Radical