The Influence of Suspended Solids on the Combined Toxicity of Galaxolide and Lead to Daphnia magna

Polycyclic musks and heavy metals are often present in natural aquatic environment. The aims of this study were to evaluate the toxic effects on Daphnia magna from exposure to the polycyclic musks and the heavy metals in combination with stress from suspended solids exposure. Galaxolide and lead were used as typical pollutants. The toxic effects on D. magna decreased with addition of suspended solids within the single experiments having galaxolide after 24 and 48 h. A similar result was observed for the toxic effect of lead on the D. magna with adding suspended solids during exposure. Synergism on D. magna was found within the combined tests having galaxolide and lead during the 24 and 48 h exposure based on additive index analysis. The combined toxic effect of galaxolide and lead was significantly decreased by adding suspended solids. The results could provide useful information for the toxic risks assessments of surface aquatic systems.