Biodegradability of nonaqueous-phase liquids affects the mineralization of phenanthrene in soil because of microbial competition

Journal Article · Fri Aug 01 04:00:00 EDT 1997 · Environmental Toxicology and Chemistry

DOI:https://doi.org/10.1002/etc.5620160801· OSTI ID:538153

Morrison, D E; Alexander, M ^[1]

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1. Cornell Univ., Ithaca, NY (United States)

A study was conducted to determine the effects of biodegradability of nonaqueous-phase liquids (NAPLs) and microbial competition on the biodegradation in soil of a constituent of the NAPLs. The rates of mineralization of phenanthrene dissolved in 8 mg of 2,2,4,4,6,8,8-heptamethylnonane (HMN), di(2-ethylhexyl) phthalate (DEHP), or pristane per g of soil were faster than the rates when the compound was dissolved in hexadecane or dodecane. Addition of inorganic N and P to the soil increased the mineralization rate in the first two but not the last two NAPLs. N and P addition did not enhance mineralization of phenanthrene when added in 500 {micro}g of hexadecane, pristane, or HMN per g of soil. Hexadecane was rapidly degraded, pristane was slowly metabolized, DEHP was still slower, and HMN was not mineralized in the test period. Mixing the soil stimulated mineralization of phenanthrene dissolved in HMN but not in hexadecane. Mineralization of phenanthrene dissolved in HMN was the same if the gas phase contained 21%, 2.1%, or traces of O{sub 2}. In contrast, the biodegradation of phenanthrene dissolved in hexadecane, although the same at 21 and 2.1% O{sub 2}, was not observed if traces of O{sub 2} were present. The mineralization was slower in unshaken soil-water mixtures if phenanthrene was added in hexadecane than in HMN or pristane, but the rates with the 3 NAPLs were increased by shaking the suspensions. The authors suggest that the biodegradability of major components of NAPLs and microbial competition for N, P, or O{sub 2} will have a major impact on the rate of transformation of minor constituents of NAPLs.

• Sponsoring Organization: USDOE
• OSTI ID: 538153
• Journal Information: Environmental Toxicology and Chemistry, Journal Name: Environmental Toxicology and Chemistry Journal Issue: 8 Vol. 16; ISSN ETOCDK; ISSN 0730-7268
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
BIODEGRADATION
IN-SITU PROCESSING
MICROORGANISMS
MINERALIZATION
NUTRIENTS
ORGANIC COMPOUNDS
PHENANTHRENE
REMEDIAL ACTION
SOIL CHEMISTRY
SOILS