|Environmental Fate|| TERRESTRIAL FATE: Octachloronaphthalene has estimated Koc values of
750,000-1,600,000(1,SRC); according to a suggested classification scheme , these estimated
Koc values suggest that octachloronaphthalene will be essentially immobile in soil; therefore,
leaching should not be an important fate process. There are no known abiotic processes
that will degrade octachloronaphthalene within soil systems. Some surface photolysis may be
possible on soil surfaces exposed to sunlight, but insufficient data are available to predict its
potential importance. Octachloronaphthalene's large number of aromatic chloride
substituents suggests that it will not biodegrade fast in soil ; its biodegradability has been
reported as "poor" ; therefore, octachloronaphthalene may be relatively persistent in soil.
AQUATIC FATE: Volatilization and adsorption to sediment may be an important transport
processes for octachloronaphthalene in water. In the absence of strong adsorption, volatilization
half-lives of 43 hr and 19.5 days have been estimated for a model river (one meter deep) and
environmental pond (2 meters deep), respectively(1-2,SRC); with maximum adsorption, the
half-life from the pond may exceed one year(2,SRC). Estimated log Koc values of
5.88-6.20(1,SRC) suggest that partitioning from the water column to sediment and suspended
material will occur. Octachloronaphthalene's large number of aromatic chloride substitutents
suggests that it will not biodegrade fast in soil ; its biodegradability has been reported as
poor ; therefore, aquatic sediments may be an important environmental sink for
octachloronaphthalene. Screening studies have measured fish bioconcentration factors
(BCFs) of 0-330(4,6); the large size of the octachloronaphthalene molecule may inhibit membrane
permeation and result in low bioconcentration .
ATMOSPHERIC FATE: Based upon an extrapolated vapor pressure of 1X10-8 mm Hg at 25
deg C(1,SRC), octachloronaphthalene can exist in both the vapor-phase and particulate-phase in
the ambient atmosphere(2,SRC); at this vapor-pressure, the particulate-phase may
dominate(2,SRC). It will degrade slowly in the atmosphere by the vapor-phase reaction with
photochemically produced hydroxyl radicals with an estimated half-life of about 437 days(3,SRC).
Direct photolysis may contribute to its atmospheric degradation. Particulate-phase
octachloronaphthalene can be physically removed from air by dry and wet deposition
EFFL: Octachloronaphthalene concns of 50-130 ug/L were detected in industrial wastewaters
from aluminum smelting processes that used either hexachloroethane-chlorine gas or
dichloroethane-Freon gas treatments .