Air Quality Criteria for Lead Volume II of II - (NEPIS)(EPA) - US ...

Tubificidae abundance. Lead was the only metal that was positively correlated to Nais species,
while other metals were negatively correlated to Tubificidae (Rosso et al., 1994).
The effects of metals and particle size on structuring epibenthic sea grass fauna (fish,
mollusks, crustaceans, and polychaetes) was evaluated near a Pb smelter in South Australia
(Ward and Young, 1982; Ward and Hutchings, 1996). Effluent from the smelter was the primary
source of Pb and other metal contamination. Species richness and composition were evaluated
near the Pb smelter along with metal concentrations in sediment. Lead levels in sediment (up to
5270 mg/kg dw) correlated with negative effects on species richness and composition, while the
other metals evaluated had similar correlations. Therefore, Pb alone could not be identified as
the sole metal causing stress.
Tissue Bioaccumulation Associated with Alterations of Community Structure
Several studies have examined the bioaccumulation of lead in aquatic systems with
indices of community structure and function. A focused study on changes in Chironomidae
community composition in relation to metal mines (New Brunswick, Canada) identified changes
in Chironomidae richness (Swansburg et al., 2002). Lead was not detected (detection limit not
given for any matrix) in the water column at any site. However, Pb levels in periphyton were
significantly higher at mining sites (40.3 to 1387 mg/kg dw) compared to reference sites (not
detected [ND], 33.3 mg/kg dw). Furthermore, Pb in chironomids was significantly higher at
mine-affected sites (1.6 to 131 mg/kg dw) compared to reference sites (ND, 10.2 mg/kg dw).
The concentrations in biota indicate that Pb is mobile and available to the aquatic community
even though water concentrations were undetectable. Chironomidae richness was reduced at the
sites receiving mining effluent containing Pb, Cd, Cu, and Zn.
In another study, macroinvertebrate lead tissue concentrations (32.2 to 67.1 mg/kg dw at
affected sites) collected from the Clark Fork River, Montana correlated negatively with total
richness, EPT richness, and density (Poulton et al., 1995). Mean Pb levels were as high as
67.1 mg/kg dw at sites most affected by lead. However, other metals, including Cd, Cu, and Zn,
also were negatively correlated with total richness and EPT richness. Therefore, attribution of
the observed effects to Pb is difficult, as other metals may be contributing factors.
In Montana, the potential effects of metals on macroinvertebrate communities in the
Boulder River watershed were evaluated (Rhea et al., 2004). Similar to the approach taken by
AX7-205