Exploring the Balance between Sources, Deposition, and the Environmental Burden of PCDD/Fs in the U.K. Terrestrial Environment:  An Aid To Identifying Uncertainties and Research Needs

Abstract

The United Kingdom is used as a study area in which to examine (i) the relationship between primary and potential secondary emissions of PCDD/Fs; (ii) the balance between atmospheric emissions and deposition; and (iii) the contemporary environmental burden of PCDD/Fs and possible historical input profiles. This critical review exercise is seen as an important aid to identifying gaps in knowledge and research needs and directing a scientifically sound strategy for PCDD/F risk reduction. The paper focuses on two key compartments, air and soil, as these play an important role in the movement and storage of PCDD/Fs. The terrestrial agricultural food chain supplies the majority of human exposure to PCDD/Fs via the pathway air−deposition−crop/pasture/soil−grazing animals−meat/dairy products−human diet. Primary emissions of PCDD/Fs to the atmosphere are expected to decline in the future following the implementation of new legislative controls. This should be reflected by a further decline in ambient air concentrations, as our calculations indicate that primary emissions are currently the main PCDD/F sources to air. The soil burden will take much longer to decline, due to the extreme persistence of these compounds in this environmental matrix. The paper highlights uncertainties and future research needs concerning the environmental sources, fate, and behavior of this group of compounds.

Body Loadings and Health Risk Assessment of Polychlorinated Dibenzo-p-dioxins and Dibenzofurans at an Intensive Electronic Waste Recycling Site in China

“…These three congeners constituted up to 65-92%. The homologue profiles indicate the environmental fate and sources of dioxins (49). The samples of each TZ or HZ donor showed similar profiles to those of the representative profiles (obtained by using the average concentrations).…”

Long-term persistence of polychlorinated dibenzo-p-dioxins and dibenzofurans in air, soil and sediment around an abandoned pentachlorophenol factory in China

“…Consequently, the potential environmental legacy from these sites remains a great concern. Further, PCDD/Fs can be transported from contaminated sites via volatilization or particlebound transport to the atmospheric environment as secondary sources (DuarteDavidson et al, 1997). However, information on the levels of PCDD/Fs in atmosphere surrounding deserted PCP plants is scarce.…”

Levels and distribution of organochlorine pesticides in various media in a mega-city, China

“…Soil generally acts as a primary sink and emission source for contaminants (Duarte-Davidson et al, 1997;Rauf et al, 2002). Atmospheric particulates are important factors in the long distance transport of contaminants in the terrestrial ecosystem (Hoff et al, 1998).…”