Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Hexachlorobenzene in the global environment: Emissions, levels, distribution, trends and processes.
AU - Barber, Jonathan L.
AU - Sweetman, Andrew J.
AU - van Wijk, Dolf
AU - Jones, Kevin C.
PY - 2005/7
Y1 - 2005/7
N2 - Hexachlorobenzene (HCB) is considered here as a ‘model persistent organic pollutant.’ Data on its sources, emissions, environmental levels and distributions and trends are compiled and used to assess its fate and behaviour in the global environment. Consideration is given as to the extent to which it has undergone repeated air-surface exchange or ‘hopping’ to become globally dispersed, the balance between primary and secondary sources in maintaining ambient levels, and its ultimate sinks in the environment. Global production exceeded 100,000 tonnes and primary emissions to atmosphere probably peaked in the 1970s. There has been a consistent downward trend in the environment over the past 20 years. Temporal trends of HCB in the environment vary, dependent on time period measured, media studied and study location, but the average half-life from all the studies is 9 years. Estimates are made of the contemporary burden in the environment; these range between 10,000 and 26,000 tonnes and are dominated by the loadings in treated and background soils, sediments and oceans. Estimates of the trends of HCB emissions from treated soils are derived. At its peak, the amount of HCB emitted from soil to air may have been in the hundreds to thousands of tonnes per year, which would have made it a significant source of HCB to the environment. Whilst the amount of HCB being emitted from contemporary soil is much lower, only a small amount of re-emission of HCB from soil to air is required to maintain contemporary air concentrations under the current primary emission scenario.
AB - Hexachlorobenzene (HCB) is considered here as a ‘model persistent organic pollutant.’ Data on its sources, emissions, environmental levels and distributions and trends are compiled and used to assess its fate and behaviour in the global environment. Consideration is given as to the extent to which it has undergone repeated air-surface exchange or ‘hopping’ to become globally dispersed, the balance between primary and secondary sources in maintaining ambient levels, and its ultimate sinks in the environment. Global production exceeded 100,000 tonnes and primary emissions to atmosphere probably peaked in the 1970s. There has been a consistent downward trend in the environment over the past 20 years. Temporal trends of HCB in the environment vary, dependent on time period measured, media studied and study location, but the average half-life from all the studies is 9 years. Estimates are made of the contemporary burden in the environment; these range between 10,000 and 26,000 tonnes and are dominated by the loadings in treated and background soils, sediments and oceans. Estimates of the trends of HCB emissions from treated soils are derived. At its peak, the amount of HCB emitted from soil to air may have been in the hundreds to thousands of tonnes per year, which would have made it a significant source of HCB to the environment. Whilst the amount of HCB being emitted from contemporary soil is much lower, only a small amount of re-emission of HCB from soil to air is required to maintain contemporary air concentrations under the current primary emission scenario.
KW - Hexachlorobenzene
KW - Sources
KW - Emissions
KW - Soils
KW - Sediments
KW - Air
KW - Trends
KW - Fate
KW - Global budget
U2 - 10.1016/j.scitotenv.2005.03.014
DO - 10.1016/j.scitotenv.2005.03.014
M3 - Journal article
VL - 349
SP - 1
EP - 44
JO - Science of the Total Environment
JF - Science of the Total Environment
SN - 0048-9697
IS - 1-3
ER -