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These findings allow the conclusion that trifluralin is stable enough to be present in the 
marine environment of the North Sea and Baltic Sea. Concentrations are highest during 
and after the main application season in winter. The 10 times lower concentrations in 
summer indicate a moderately fast degradation of trifluralin in the (marine) 
environment. The distribution pattern is best explained by a low, diffuse contamination 
level (e.g. by atmospheric deposition) with minor local input sources. 
Concentrations in the river Elbe - generally the most important input source of 
pollutants to the German Bight - are relatively low, which means that this source of 
trifluralin contamination is less important. 
In summer, the trifluralin levels in water exceed those of the classical lipophilic 
pollutants, e.g. HCB, DDT, or PCB, but are lower than HCH levels. Concentrations in 
winter, however, are higher than the HCH levels. Compared to other herbicides - e.g. 
atrazine, diuron or isoproturon - trifluralin concentrations are lower by a factor of about 
10 (BSH, 2005). 
Atmospheric transport and deposition is well documented. Apart from atmospheric 
transport following spraying applications, also volatilisation and escape to the 
atmosphere has been suggested as a transport path (Alegria et al. 1999, Rice et al. 1997, 
Waite et al 1995). 
Sorption to sediment had not led to significant enrichment in the sediments investigated. 
The estimated “enrichment” of trifluralin in sediment as compared to the water phase is 
about 700. Sediment thus is no major sink for this herbicide. The low values are 
remarkable considering the relatively high log Kow of 5.3 and the reported persistence 
in soil. (OSPAR, Background document on trifluralin, 2004). The limited accumulation 
may be due to rather rapid (photo)degradation. 
Compared to classical pollutants, concentrations of trifluralin in sediment are low. At 
the station KS 11, for example, HCH isomers range between 10 and 200 ng/kg. The 
more lipophilic DDD and CB153 range from 1000 to 5000 ng/kg. PAH, e.g. BaP, have 
levels of 40 to 240 pg/kg in sediment.