TY - JOUR

T1 - Bioaccumulation of Benzo[a]pyrene Nonextractable Residues in Soil by Eisenia fetida and Associated Background-level Sublethal Genotoxicity (DNA Single-strand Breaks)

AU - Umeh, Anthony C.

AU - Panneerselvan, Logeshwaran

AU - Duan, Luchun

AU - Naidu, Ravi

AU - Semple, Kirk

N1 - This is the author’s version of a work that was accepted for publication in Science of the Total Environment. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Science of the Total Environment, ?, ?, 2019 DOI: 10.1016/j.scitotenv.2019.07.045

PY - 2019/7/4

Y1 - 2019/7/4

N2 - The potential for bioaccumulation and associated genotoxicity of nonextractable residues (NERs) of polycyclic aromatic hydrocarbon (PAHs) in long-term contaminated soils have not been investigated. Here were report research in which earthworms, Eisenia fetida, were exposed to a soil containing readily available benzo [a]pyrene (B [a]P) and highly sequestered B [a] P NERs aged in soil for 350 days. B [a] P bioaccumulation was assessed and DNA damage (as DNA single strand breaks) in earthworm coelomocytes were evaluated by comet assay. The concentrations of B [a] P in earthworm tissues were generally low, particularly when the soil contained highly sequestered B [a] P NERs, with biota-soil accumulation factors ranging from 0.6 to 0.8 kgOC/kglipid. The measurements related to genotoxicity, that is percentage (%) of DNA in the tails and olive tail moments, were significantly greater (p < 0.05) in the spiked soil containing readily available B [a] P than in soil that did not have added B [a]P. For example, for the soil initially spiked at 10 mg/kg, the percentage of DNA in the tails (29.2%) of coelomocytes after exposure of earthworms to B [a]P-contaminated soils and olive tail moments (17.6) were significantly greater (p < 0.05) than those of unspiked soils (19.6% and 7.0, for percentage of DNA in tail and olive tail moment, respectively). There were no significant (p > 0.05) differences in effects over the range of B [a] P concentrations (10 and 50 mg/kg soil) investigated. In contrast, DNA damage after exposure of earthworms to B [a] P NERs in soil did not differ from background DNA damage in the unspiked soil. These findings are useful in risk assessments as they can be applied to minimise uncertainties associated with the ecological health risks from exposure to highly sequestered PAH residues in long-term contaminated soils.

AB - The potential for bioaccumulation and associated genotoxicity of nonextractable residues (NERs) of polycyclic aromatic hydrocarbon (PAHs) in long-term contaminated soils have not been investigated. Here were report research in which earthworms, Eisenia fetida, were exposed to a soil containing readily available benzo [a]pyrene (B [a]P) and highly sequestered B [a] P NERs aged in soil for 350 days. B [a] P bioaccumulation was assessed and DNA damage (as DNA single strand breaks) in earthworm coelomocytes were evaluated by comet assay. The concentrations of B [a] P in earthworm tissues were generally low, particularly when the soil contained highly sequestered B [a] P NERs, with biota-soil accumulation factors ranging from 0.6 to 0.8 kgOC/kglipid. The measurements related to genotoxicity, that is percentage (%) of DNA in the tails and olive tail moments, were significantly greater (p < 0.05) in the spiked soil containing readily available B [a] P than in soil that did not have added B [a]P. For example, for the soil initially spiked at 10 mg/kg, the percentage of DNA in the tails (29.2%) of coelomocytes after exposure of earthworms to B [a]P-contaminated soils and olive tail moments (17.6) were significantly greater (p < 0.05) than those of unspiked soils (19.6% and 7.0, for percentage of DNA in tail and olive tail moment, respectively). There were no significant (p > 0.05) differences in effects over the range of B [a] P concentrations (10 and 50 mg/kg soil) investigated. In contrast, DNA damage after exposure of earthworms to B [a] P NERs in soil did not differ from background DNA damage in the unspiked soil. These findings are useful in risk assessments as they can be applied to minimise uncertainties associated with the ecological health risks from exposure to highly sequestered PAH residues in long-term contaminated soils.

KW - Benzo[a]pyrene nonextractable residues

KW - Long-term contaminated soil

KW - Biota-soil accumulation factor

KW - Genotoxicity

KW - Comet assay

KW - Risk assessment

U2 - 10.1016/j.scitotenv.2019.07.045

DO - 10.1016/j.scitotenv.2019.07.045

M3 - Journal article

JO - Science of the Total Environment

JF - Science of the Total Environment

SN - 0048-9697

ER -