TY - JOUR

T1 - Effects of phenanthrene and its nitrogen-heterocyclic analogues aged in soil on the earthworm Eisenia fetida

AU - Anyanwu, Ihuoma

AU - Semple, Kirk Taylor

N1 - This is the author’s version of a work that was accepted for publication in Applied Soil Ecology. 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 Applied Soil Ecology, 105, 2016 DOI: 10.1016/j.apsoil.2016.04.014

PY - 2016/9

Y1 - 2016/9

N2 - Major sources of homocyclic polycyclic aromatic hydrocarbons (PAHs) and N-containing analogues (N-PAHs) are found in the environment after being discharged through petrogenic, pyrogenic and biogenic activities. Using a health index tool and the OECD guideline 207, the ecotoxicity of phenanthrene and its nitrogen-containing analogues to the earthworm Eisenia fetida were assessed in agricultural soil at different times after spiking. The effects were measured over a 21 d exposure period (over time), during which earthworms’ general health condition, mortality and biomass were assessed. The LC50 and EC50 (based on weight loss) ranged from 400–500 mg kg−1 dry soil and 1.2–500 mg kg−1 dry soil, respectively. The N-PAHs were more toxic to E. fetida and over time more available in soil than the homocyclic-phenanthrene analogue. Benzo[h]quinoline (B[h]Q) was the most toxic and persistent of the chemicals. Furthermore, the observed physical damages to the earthworms showed that N-PAHs, especially B[h]Q, may have cellular autolytic impact on E. fetida. These findings offer new insight on the toxicity of aromatics in soil which might be useful in risk assessment of contaminated sites.

AB - Major sources of homocyclic polycyclic aromatic hydrocarbons (PAHs) and N-containing analogues (N-PAHs) are found in the environment after being discharged through petrogenic, pyrogenic and biogenic activities. Using a health index tool and the OECD guideline 207, the ecotoxicity of phenanthrene and its nitrogen-containing analogues to the earthworm Eisenia fetida were assessed in agricultural soil at different times after spiking. The effects were measured over a 21 d exposure period (over time), during which earthworms’ general health condition, mortality and biomass were assessed. The LC50 and EC50 (based on weight loss) ranged from 400–500 mg kg−1 dry soil and 1.2–500 mg kg−1 dry soil, respectively. The N-PAHs were more toxic to E. fetida and over time more available in soil than the homocyclic-phenanthrene analogue. Benzo[h]quinoline (B[h]Q) was the most toxic and persistent of the chemicals. Furthermore, the observed physical damages to the earthworms showed that N-PAHs, especially B[h]Q, may have cellular autolytic impact on E. fetida. These findings offer new insight on the toxicity of aromatics in soil which might be useful in risk assessment of contaminated sites.

KW - N-PAHs

KW - Phenanthrene

KW - Ecotoxicity

KW - Health index

KW - Earthworms

U2 - 10.1016/j.apsoil.2016.04.014

DO - 10.1016/j.apsoil.2016.04.014

M3 - Journal article

VL - 105

SP - 151

EP - 159

JO - Applied Soil Ecology

JF - Applied Soil Ecology

SN - 0929-1393

ER -