Temporal trends and sources of PCDD/Fs, pentachlorophenol and chlornitrofen in paddy field soils along the Yoneshiro River basin, Japan

• Published in: Environmental pollution (1987) 2008-12, Vol.156 (3), p.1233-1242
• Main Authors: Kobayashi, Jun, Sakai, Mizuki, Kajihara, Hideo, Takahashi, Yukio
• Format: Article
• Language: English
• Subjects: Agriculture; Applied sciences; atmospheric deposition; Biodegradation, Environmental; Biological and physicochemical properties of pollutants. Interaction in the soil; chemical concentration; chemical degradation; chlornitrofen; Earth sciences; Earth, ocean, space; ecotoxicology; Engineering and environment geology. Geothermics; Environmental Monitoring - methods; Exact sciences and technology; Freshwater; Herbicide; herbicide residues; herbicides; irrigation water; Japan; Paddy soil; paddy soils; PCDD/Fs; pentachlorophenol; Pentachlorophenol - analysis; pesticide persistence; Phenyl Ethers - analysis; pollutants; Pollution; Pollution, environment geology; polychlorinated dibenzodioxins; Polychlorinated Dibenzodioxins - analogs & derivatives; Polychlorinated Dibenzodioxins - analysis; Soil - analysis; Soil and sediments pollution; Soil Pollutants - analysis; soil pollution; Source; Temporal trend; temporal variation; Time Factors; toxic equivalency; Waste Management; Water Pollutants, Chemical - analysis; water pollution
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2008.03.012

In order to understand the long-term behaviors of polychlorinated dibenzo- p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), pentachlorophenol (PCP), and 2,4,6-trichlorophenyl-4′-nitrophenyl ether (chlornitrofen, CNP) in paddy soil, we measured their concentrations in paddy soil samples collected in 1982 and 1984 (1980s) and in 2000 and 2002 (2000s) from the Yoneshiro River basin, Japan. The concentrations of PCP and CNP decreased from the 1980s to the 2000s, whereas the concentrations of PCDD/Fs and their toxic equivalency (WHO2006-TEQ) remained. The major sources of PCDD/Fs in the paddy soil samples were attributed to impurities in PCP and CNP as a result of comparisons of homologue and congener profiles and principal component analysis. Based on the results of comparison of total input and remaining amount, it is estimated that more than 99% of PCP and CNP applied to the paddy fields had disappeared, whereas most of the applied PCDD/Fs and TEQ remained. Most of PCDD/Fs originating from PCP and CNP applied to paddy soil remained in the soil.