Lead Speciation and Bioavailability in Apatite-Amended Sediments
The in situ sequestration of lead (Pb) in sediment with a phosphate amendment was investigated by Pb speciation and bioavailability. Sediment Pb in preamendment samples was identified as galena (PbS) with trace amounts of absorbed Pb. Sediment exposed to atmospheric conditions underwent conversion t...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2011-01-01
|
| Series: | Applied and Environmental Soil Science |
| Online Access: | http://dx.doi.org/10.1155/2011/689568 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1832562118428196864 |
|---|---|
| author | Kirk G. Scheckel Aaron G. B. Williams Gregory Mc Dermott David Gratson Dean Neptune James A. Ryan |
| author_facet | Kirk G. Scheckel Aaron G. B. Williams Gregory Mc Dermott David Gratson Dean Neptune James A. Ryan |
| author_sort | Kirk G. Scheckel |
| collection | DOAJ |
| description | The in situ sequestration of lead (Pb) in sediment with a phosphate amendment was investigated by Pb speciation and bioavailability. Sediment Pb in preamendment samples was identified as galena (PbS) with trace amounts of absorbed Pb. Sediment exposed to atmospheric conditions underwent conversion to hydrocerussite and anglesite. Sediments mixed with apatite exhibited limited conversion to pyromorphite, the hypothesized end product. Conversion of PbS to pyromorphite is inhibited under reducing conditions, and pyromorphite formation appears limited to reaction with pore water Pb and PbS oxidation products. Porewater Pb values were decreased by 94% or more when sediment was amended with apatite. The acute toxicity of the sediment Pb was evaluated with Hyalella azteca and bioaccumulation of Pb with Lumbriculus variegatus. The growth of H. azteca may be mildly inhibited in contaminated sediment, with apatite-amended sediments exhibiting on average a higher growth weight by approximately 20%. The bioaccumulation of Pb in L. variegatus tissue decreased with increased phosphate loading in contaminated sediment. The study indicates limited effectiveness of apatite in sequestering Pb if present as PbS under reducing conditions, but sequestration of porewater Pb and stabilization of near-surface sediment may be a feasible and alternative approach to decreasing potential toxicity of Pb. |
| format | Article |
| id | doaj-art-8a580823018a4a43b01ec5ae90b27aea |
| institution | Kabale University |
| issn | 1687-7667 1687-7675 |
| language | English |
| publishDate | 2011-01-01 |
| publisher | Wiley |
| record_format | Article |
| series | Applied and Environmental Soil Science |
| spelling | doaj-art-8a580823018a4a43b01ec5ae90b27aea2025-02-03T01:23:20ZengWileyApplied and Environmental Soil Science1687-76671687-76752011-01-01201110.1155/2011/689568689568Lead Speciation and Bioavailability in Apatite-Amended SedimentsKirk G. Scheckel0Aaron G. B. Williams1Gregory Mc Dermott2David Gratson3Dean Neptune4James A. Ryan5USEPA, 5995 Center Hill Avenue, Cincinnati, OH 45224, USAEastern Research Group, Inc., 10200 Alliance Road, Suite 190, Cincinnati, OH 45242, USANeptune and Company, Inc., 8962 Spruce Ridge Road, Fairfax Station, VA 22039, USANeptune and Company, Inc., 8962 Spruce Ridge Road, Fairfax Station, VA 22039, USANeptune and Company, Inc., 8962 Spruce Ridge Road, Fairfax Station, VA 22039, USAUSEPA, 5995 Center Hill Avenue, Cincinnati, OH 45224, USAThe in situ sequestration of lead (Pb) in sediment with a phosphate amendment was investigated by Pb speciation and bioavailability. Sediment Pb in preamendment samples was identified as galena (PbS) with trace amounts of absorbed Pb. Sediment exposed to atmospheric conditions underwent conversion to hydrocerussite and anglesite. Sediments mixed with apatite exhibited limited conversion to pyromorphite, the hypothesized end product. Conversion of PbS to pyromorphite is inhibited under reducing conditions, and pyromorphite formation appears limited to reaction with pore water Pb and PbS oxidation products. Porewater Pb values were decreased by 94% or more when sediment was amended with apatite. The acute toxicity of the sediment Pb was evaluated with Hyalella azteca and bioaccumulation of Pb with Lumbriculus variegatus. The growth of H. azteca may be mildly inhibited in contaminated sediment, with apatite-amended sediments exhibiting on average a higher growth weight by approximately 20%. The bioaccumulation of Pb in L. variegatus tissue decreased with increased phosphate loading in contaminated sediment. The study indicates limited effectiveness of apatite in sequestering Pb if present as PbS under reducing conditions, but sequestration of porewater Pb and stabilization of near-surface sediment may be a feasible and alternative approach to decreasing potential toxicity of Pb.http://dx.doi.org/10.1155/2011/689568 |
| spellingShingle | Kirk G. Scheckel Aaron G. B. Williams Gregory Mc Dermott David Gratson Dean Neptune James A. Ryan Lead Speciation and Bioavailability in Apatite-Amended Sediments Applied and Environmental Soil Science |
| title | Lead Speciation and Bioavailability in Apatite-Amended Sediments |
| title_full | Lead Speciation and Bioavailability in Apatite-Amended Sediments |
| title_fullStr | Lead Speciation and Bioavailability in Apatite-Amended Sediments |
| title_full_unstemmed | Lead Speciation and Bioavailability in Apatite-Amended Sediments |
| title_short | Lead Speciation and Bioavailability in Apatite-Amended Sediments |
| title_sort | lead speciation and bioavailability in apatite amended sediments |
| url | http://dx.doi.org/10.1155/2011/689568 |
| work_keys_str_mv | AT kirkgscheckel leadspeciationandbioavailabilityinapatiteamendedsediments AT aarongbwilliams leadspeciationandbioavailabilityinapatiteamendedsediments AT gregorymcdermott leadspeciationandbioavailabilityinapatiteamendedsediments AT davidgratson leadspeciationandbioavailabilityinapatiteamendedsediments AT deanneptune leadspeciationandbioavailabilityinapatiteamendedsediments AT jamesaryan leadspeciationandbioavailabilityinapatiteamendedsediments |