PW10 Bioaccumulation and Biomagnification
Exhibit Hall
8:00 AM - Wednesday
(PW171) Uptake of Antimony, Copper, and Lead into Plants, Invertebrates, Reptiles, and Mammals at a Small Arms Firing Range in Central California.
DeShields, B1, Pattanayek, M1, DiMundo, G2, Navarro, Neal3, 1 BBL Sciences, Petaluma, CA, USA2 MACTEC E & I, Petaluma, CA, USA3 U.S. Army Corps of Engineers, Sacramento, CA, USA
ABSTRACT- A study was conducted at the Multi-Range Area at Fort Ord, California to evaluate the uptake of antimony, copper, and lead into plants, insects, lizards, and small mammals from soil to provide data for the ecological risk assessment and in support of remedial planning efforts. Locations representing no, low, moderate, and high bullet cover range areas were sampled. For plants, vegetative portions were collected. Insects were collected by a variety of techniques and composited. For a subset of the mammals, bone, kidney, feces, and remainder tissues were analyzed; whole body analyses were conducted on the remainder of the mammals and the lizards. All samples were analyzed for lead, antimony, and copper. Additionally, in vitro bioavailability tests were conducted on lead in soil from the 250 um and 500 um sieve fraction at pH values of 1.5 and 4.5. In general, good correlations were found between tissues and both lead and antimony soil concentrations; most of the relationships were lognormal. Copper was not taken up to a high degree except where soil concentrations of copper were significantly elevated; therefore, the correlations between soil and tissue copper levels were poor. The highest concentrations of metals were found in biota collected from high bullet cover zones with a significant decrease in tissue concentrations in areas of lesser bullet cover. For small mammals, the highest lead concentrations were found in the bone; lead concentrations in the kidneys of small mammals were below the screening level of 25 mg/kg. Lead was found at up to 872 mg/kg in plants, 485 mg/kg in insects, 220 mg/kg in lizards, and 23.5 mg/kg in small mammals. The in vitro tests showed that bioaccessibility decreases with increasing soil lead concentration at pH 1.5; an opposite relationship was shown at pH 4.5. Bioaccessibility ranged from 26 to 93% in high bullet cover zones at pH 1.5, whereas the bioaccessibility ranged from less than 1 to 14.5% at pH 4.5 in the 250 um fraction; bioaccessibility in the 500 um fraction was consistently higher.
Key words: bioaccumulation, lead, bioavailability