162

Table  62:  Overview  of  PCP  concentrations  in  the  environment.

Sample

Sampling
location

Sampling  date

Concentration
[ng/L]/[pg/kg  dry
wt]

Limit  of
detection
[ng/L]/[pg/kg]

Sea  water

North  Sea;
estuaries

1983-1997

6-100  a

-

Sea  water

German  Bight

1988

0.1  -6.4 d

Marine  sediment

North  Sea;
estuaries

1991-1994

26.5(max.  value) 3

<10

River  water

Rhine

1999

30  b

-

River  sediment

Netherlands

1980

0.2-1.5  c

0.1

Data  from:  “(Eurochlor,  1997);  b (RIWA,  2002);  c (Wegman,  1983),  d (HiihnerfuB  et  al.,  1990)

6.2.5  Trifluralin

F 3 C

no 2

NO,

(CHJ 2 -CH,
(Cl“^) 2  CHg

Figure  28:  Structure  of  Trifluralin.

Trifluralin  (Figure  28)  is  a  dinitroaniline  derivative  which  is  used  as  a  selective
herbicide.  It  has  a  low  water  solubility  and  a  high  affinity  for  soil.  The  substance  is
marketed  under  different  trade  names  (e.  g.  TREFLAN  (Trifluralin  480  g/L))  for  presowing ­
  treatment  of  grasses  and  dicotyledonous  weeds  (Extoxnet  Information  on
Trifluralin,  1996;  Dow  AgroScience,  2005).  It  was  first  registered  in  the  US  in  1963
(Pesticide  News,  2001).  In  the  European  Union,  trifluralin  is  manufactured  at  a  single
production  facility  (Manerbio,  northern  Italy).  The  production  volume  is  about  6000  t
per  year,  and  consumption  in  the  European  Union  is  32001  (OSPAR  Background
Document  on  trifluralin,  2004).  Trifluralin  is  subject  to  rapid  photodegradation  in  air  but
is  persistent  in  sediment.  Under  aerobic  as  well  as  anaerobic  conditions,  several
metabolites  of  trifluralin  have  been  observed,  which  points  to  its  degradability  in  the
environment.