Toxicological interactions of ibuprofen and triclosan on biological activity of activated sludge.

The growing use of pharmaceutical and personal care products increases their concentrations in the wastewater entering treatment plants and their levels into biological reactors. The most extended biological wastewater treatment is the activated sludge process. The toxicity of ibuprofen and triclosan, individually and combined, was studied by tracking the biological activity of the activated sludge measuring oxygen uptake rate and the inhibition of the esterase activity. Short-term exposure produced significant inhibition in oxygen uptake, with lower damage to enzymatic activity. Median effect values for oxygen uptake inhibition were 64±13mgL