This strong influence of
environmental parameters onCu toxicity to FWorganisms is recognized by the USEPA and has been incorporated into a Biotic
Ligand Model (BLM) that is currently employed to allow for
the establishment of site specific water quality criteria (USEPA,
2003). The FWBLMuseswater chemistry to predict the amount
of Cu which will accumulate on/in the gill of a FW organism
and estimates toxicity from a relationship between gill Cu accu
mulation and mortality. The gill was chosen as the target organ
for BLM modeling because multiple studies demonstrate that
this organ rapidly accumulates Cu following the onset of water
borne exposure and this results in the disturbance of multiple
physiological processes.