fig6

Figure 6. Percentage of free silver (Ag⁺) and silver complexes (AgL) smaller than the membrane pores (< 3 kDa) plotted against exposure time for AgPEG dispersed in algae and Daphnia media at pH 6, 7, and 8 in the absence and presence of (A) the HSs from the Sorocabinha River and (B) EPSs from Raphidocelis subcapitata. AgPEG = 1 µg L^-1, AgPEG = 1 µg L^-1 + HS = 1 mg L^-1, AgPEG= 1 µg L^-1 + HS = 10 mg L^-1, AgPEG = 100 µg L^-1, AgPEG = 100 µg L^-1 + HS = 1 mg L^-1, AgPEG = 100 µg L^-1 + HS = 10 mg L^-1, AgPEG = 1 µg L^-1 + EPS = 1 mg L^-1, AgPEG = 1 µg L^-1 + EPS = 5 mg L^-1, AgPEG = 100 µg L^-1 + EPS = 1 mg L^-1, AgPEG = 100 µg L^-1 + EPS = 5 mg L^-1. The error bars indicate the standard deviations of triplicate measurements. HS = humic substances, EPS = extracellular polymeric substances, AgPEG = silver nanoparticles capped with polyethylene glycol.