Dichlobenil

Other distribution data

Administrative data

Endpoint:

other distribution data

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

October 1988 to 02 June 1989

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1989

Report date:

1989

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: EPA Guideline 163-1

Deviations:

no

GLP compliance:

yes

Type of study:

soil leaching

Media:

soil - air

Test material

Test material information

Constituent 1

Reference substance name:

Dichlobenil

EC Number:

214-787-5

EC Name:

Dichlobenil

Cas Number:

1194-65-6

Molecular formula:

C7H3Cl2N

IUPAC Name:

2,6-dichlorobenzonitrile

Test material form:

solid: particulate/powder

Details on test material:

- Name of test material (as cited in study report): [U]14C]-2,6-dichlorobenzonitrile
- Lot/batch No.: AOI87HO5A
- Radiochemical purity (if radiolabelling): 98.9 % (radiolabel); 98.8 % (chemical)
- Specific activity (if radiolabelling): 16.9 mCi/g (625 MBq/g)
- Locations of the label (if radiolabelling): phenyl ring

Results and discussion

Any other information on results incl. tables

The average amount of [14C]-dichlobenil equivalents added to each column was 73.8 µg consisting of 63.3 µg test material, 2.2 µg 2,6-dichlorobenzamide and 5.7 µg bound residue.

After leaching with 2 L water, volume and radioactivity of the effluent were determined, amounting to approximately 3% of the applied amount of radioactivity (see Table 1). Identification of the radioactivity in the leachate was not performed as the volume was too large compared to the total amount of radioactivity present.

Table 1: Volume and radioactivity recorded of the effluent

	Column 1		Column 2
Time (days)	Volume (mL)	Radioactivity (% of added)	Volume (mL)	Radioactivity (% of added)
3	596	<0.4	547	<0.4
4	251	0.2	232	0.4
5	273	1.3	240	1.1
6	227	0.6	209	0.6
7	210	0.3	191	0.3
12	417	0.5	499	0.6
Total	1974	3.0	1918	3.1

The amounts of radioactivity present at various depths in the sandy loam column are summarised in Table 2.

Table 2: Distribution of radioactivity in columns (µg)

	Column 1		Column 2
Sediment code and depth (cm)	Extractable	Non-extractable	Extractable	Non-extractable
C (1)	6.83	1.1	6.63	1.4
B1 (3)	10.71	1.4	n.d	n.d
B2 (5)	10.82	0.8	12.43	0.9
B3 (7)	13.97	1.1	11.00	0.8
B4 (9)	11.82	0.8	9.65	<0.7
B5 (11)	6.50	<0.7	7.09	<0.8
B6 (13)	0.58	<0.5	1.97	<0.6
B7 (15)	<0.24	<0.6	n.d.	n.d.
B8 (17)	<0.24	<0.7	<0.24	<0.7
B9 (19)	<0.08	<0.6	<0.08	<0.6
B10 (21)	<0.08	<0.7	<0.08	<0.6
B11 (23)	<0.08	<0.7	<0.08	<0.7
B12 (25)	n.d	n.d.	<0.08	<0.7
B13 (27)	<0.08	<0.6	<0.08	<0.6
B14 (29)	<0.08	<0.7	<0.08	<0.6
B15 (31)	<0.08	<0.8	<0.08	<0.7
Total	61.23	5.2	48.77	2.8

n.d. = not determined due to breakage (soil was spilled)

As most of the radioactivity was primarily found in the top 15 cm layer, identification has been performed for that part only. The radioactivity consisted mainly of test material (87 -92 %), 2,6 -dichlorobenzamide (1.8 -3.7 %) and approximately 6 % on the column was non-extractable.

Applicant's summary and conclusion

Conclusions:

Under the conditions of the test, after 31 days ageing, the test material does not penetrate further than 15 cm in a sandy loam soil whereas only 3 % of the aged residue had leached through the column.

Executive summary:

In a GLP compliant aged residue column leaching study conducted in line with standardised guideline EPA 163-1, the mobility of the test material was determined. Under the conditions of the test, the test material does not penetrate further than 15 cm in sandy loam soil after 31 days ageing and only 3 % of the aged residue had leached through the column.