Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Evidence for the presence of PCDD/Fs in the environment prior to 1900 and further studies on their temporal trends.
AU - Alcock, Ruth E.
AU - McLachlan, M. S.
AU - Johnston, A. E.
AU - Jones, Kevin C.
PY - 1998/6/1
Y1 - 1998/6/1
N2 - This paper presents evidence for the existence of PCDD/Fs in the environment prior to the widespread development of the chloroaromatics and chlorine industry, by the analysis of a previously unopened bottle of soil collected in 1881 from a controlled long-term agricultural experiment at Rothamsted Experimental Station. Great care was taken to avoid contamination of the sample from dust or by exposure to modern air; an experiment was conducted to investigate the potential for contamination of the sample by such exposure. The 1881 soil sample (from the plowed 0−23 cm depth layer) contained 0.7 ng of ∑TEQ/kg soil, and there were no detectable changes in its ∑PCDD/F composition when aliquots of it were exposed over 32 days in a laboratory at Lancaster University. Modern soil sampled from the same field plot (which has never received any fertilizers or amendments) now contains 1.4 ng of ∑TEQ/kg, an increase resulting from cumulative atmospheric deposition of PCDD/Fs retained in the surface layers of the soil. Post-collection contamination issues were also addressed by PCDD/F analysis of dust and paper bags used to store more recent samples. The ∑TEQ concentration of archived herbage samples collected year-on-year from Rothamsted between 1980 and 1995 have trended downward by a factor of 3−4, implying a recent decline in the atmospheric deposition of PCDD/Fs and supporting a previously reported (Kjeller et al. Environ. Sci. Techol. 1996, 31, 458−463) longer term decline. The significance of these results is discussed.
AB - This paper presents evidence for the existence of PCDD/Fs in the environment prior to the widespread development of the chloroaromatics and chlorine industry, by the analysis of a previously unopened bottle of soil collected in 1881 from a controlled long-term agricultural experiment at Rothamsted Experimental Station. Great care was taken to avoid contamination of the sample from dust or by exposure to modern air; an experiment was conducted to investigate the potential for contamination of the sample by such exposure. The 1881 soil sample (from the plowed 0−23 cm depth layer) contained 0.7 ng of ∑TEQ/kg soil, and there were no detectable changes in its ∑PCDD/F composition when aliquots of it were exposed over 32 days in a laboratory at Lancaster University. Modern soil sampled from the same field plot (which has never received any fertilizers or amendments) now contains 1.4 ng of ∑TEQ/kg, an increase resulting from cumulative atmospheric deposition of PCDD/Fs retained in the surface layers of the soil. Post-collection contamination issues were also addressed by PCDD/F analysis of dust and paper bags used to store more recent samples. The ∑TEQ concentration of archived herbage samples collected year-on-year from Rothamsted between 1980 and 1995 have trended downward by a factor of 3−4, implying a recent decline in the atmospheric deposition of PCDD/Fs and supporting a previously reported (Kjeller et al. Environ. Sci. Techol. 1996, 31, 458−463) longer term decline. The significance of these results is discussed.
U2 - 10.1021/es9705046
DO - 10.1021/es9705046
M3 - Journal article
VL - 32
SP - 1580
EP - 1587
JO - Environmental Science and Technology
JF - Environmental Science and Technology
SN - 0013-936X
IS - 11
ER -