Wild, S. R. and Jones, K. C. and Johnston, A. E. (1992) The polynuclear aromatic hydrocarbon (PAH) content of herbage from a long-term grassland experiment. Atmospheric Environment Part A, General Topics, 26 (7). pp. 1299-1307. ISSN 0960-1686
Full text not available from this repository.Abstract
Herbage samples harvested and stored from a long-term agricultural experiment started in the 1850s at Rothamsted Experimental Station (U.K.) have been analysed for polynuclear aromatic hydrocarbons (PAHs). The changing PAH content of samples since 1900 is thought to reflect broadly changes in the PAH content of air. Herbage concentrations ranged between 580 and 2750 μg ΣPAH kg -1 (total of 15 compounds). The lowest concentrations since 1900 were measured in the most recent samples (since the 1960s), with the highest between 1930 and 1955. Samples taken before 1956 contain statistically lower PAH contents than samples taken after this date, suggesting a reduction in PAH emissions from local and/or national sources. Samples taken between 1860 and 1900 contained much higher concentrations of ΣPAH (between 3620 and 6550 μg ΣPAH kg -1 ) and a different mixture of compounds. These samples may have been contaminated in the drying process after harvesting and prior to storage. The ΣPAH contents of these samples therefore probably do not reflect the atmospheric burden of PAHs at that time.