Ecotoxicity of a polycyclic aromatic hydrocarbon (PAH)-contaminated soil

• Published in: Ecotoxicology and environmental safety Vol. 67; no. 2; pp. 190 - 205
• Main Authors: Eom, I.C., Rast, C., Veber, A.M., Vasseur, P.
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 01-06-2007; Elsevier
• Subjects: Animal, plant and microbial ecology; Animals; Applied ecology; Arthropods - drug effects; Arthropods - growth & development; Bioassay; Biological and medical sciences; Brassica; Brassica - drug effects; Brassica - growth & development; Brassica chinensis; Candida; Ceriodaphnia dubia; Collembola; Daphnia magna; Earthworm; Ecosystem; Ecotoxicology, biological effects of pollution; Eisenia fetida; Folsomia candida; Freshwater; Fundamental and applied biological sciences. Psychology; General aspects; Lactuca - drug effects; Lactuca - growth & development; Lactuca sativa; Mutagenicity; Mutagens - toxicity; Oligochaeta - drug effects; Oligochaeta - growth & development; Plant; Polycyclic Aromatic Hydrocarbons - toxicity; Pseudokirchneriella subcapitata; Reproduction - drug effects; Salmonella typhimurium - drug effects; Salmonella typhimurium - genetics; Soil Pollutants - toxicity; Terrestrial environment, soil, air; Toxicity Tests - methods; Vibrio fischeri; Water extract; Earthworm; Plant; Mutagenicity; Collembola; Bioassay; Water extract; Water; Ecotoxicology; Hydrocarbon; Toxicity; Insecta; Polycyclic aromatic compound; Soil pollution; Annelida; Oligochaeta; Persistent organic pollutant; Arthropoda; Environment; Invertebrata; Organic compounds
• ISSN: 0147-6513; 1090-2414
• DOI: 10.1016/j.ecoenv.2006.12.020

Soil samples from a former cokery site polluted with polycyclic aromatic hydrocarbons (PAHs) were assessed for their toxicity to terrestrial and aquatic organisms and for their mutagenicity. The total concentration of the 16 PAHs listed as priority pollutants by the US Environmental Protection Agency (US-EPA) was 2634±241
mg/kg
dw in soil samples. The toxicity of water-extractable pollutants from the contaminated soil samples was evaluated using acute (
Vibrio fischeri; Microtox
® test,
Daphnia magna) and chronic (
Pseudokirchneriella subcapitata,
Ceriodaphnia dubia) bioassays and the EC values were expressed as percentage water extract in the test media (v/v). Algal growth (EC50—3
d=2.4±0.2% of the water extracts) and reproduction of
C. dubia (EC50—7
d=4.3±0.6%) were the most severely affected, compared to bacterial luminescence (EC50—30
min=12±3%) and daphnid viability (EC50—48
h=30±3%). The Ames and Mutatox
® tests indicated mutagenicity of water extracts, while no response was found with the
umu test.
The toxicity of the soil samples was assessed on the survival and reproduction of earthworms (
Eisenia fetida)
and collembolae (
Folsomia candida), and on the germination and growth of higher plants (
Lactuca sativa L.: lettuce and
Brassica chinensis J.: Chinese cabbage). The EC50 values were expressed as percentage contaminated soil in ISO soil test medium (weight per weight—w/w) and indicated severe effects on reproduction of the collembola
F. candida (EC50—28
d=5.7%) and the earthworm
E. fetida (EC50—28
d=18% and EC50—56
d=8%, based on cocoon and juvenile production, respectively). Survival of collembolae was already affected at a low concentration of the contaminated soil (EC50—28
d=11%). The viability of juvenile earthworms was inhibited at much lower concentrations of the cokery soil (EC50—14
d=28%) than the viability of adults (EC50—14
d=74%). Only plant growth was inhibited (EC50—17
d=26%) while germination was not.
Chemical analyses of water extracts allowed us to identify inorganic water-extractable pollutants as responsible for toxicity on aquatic species, especially copper for effects on
D. magna and
C. dubia. The soil toxicity on collembolae and earthworms could be explained by 4 PAH congeners—fluorene, phenanthrene, pyrene, and fluoranthene. Yet, toxicity of the cokery soil as a whole was much lower than toxicity that could be deduced from the concentration of each congener in spiked soils, indicating that pollutants in the soil became less bioavailable with ageing.