Dichloromethylbenzene

Monitoring data

Administrative data

Endpoint:

monitoring data

Type of information:

experimental study

Adequacy of study:

other information

Study period:

1979

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: Results are not conclusive.

Justification for type of information:

The substance described in this dossier is an isomeric mixture of five position isomers of dichlorotoluene. The similarities concerning chemical structure and key intrinsic properties such as log Kow and water solubility lead to the assumption that the values for ecotoxicological endpoints will also be very similar for the individual isomers and the mixture of isomers and that therefore results obtained with isomers can be useful for the assessment of the mixture.

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Inventarisatie van organische microverontreinigingen in de Rijn in 1979 (Inventory of organic substances in the river Rhine in 1979)

Author:

Linders, J.B., H., J. et al.

Year:

1981

Bibliographic source:

Rijksinstizuut voor drinkwatervoorziening, The Netherlands

Reference 2

Reference Type:

publication

Title:

Persistent Organic Pollutants in River Water and Ground Water of the Netherlands

Author:

Zoeteman, B.C.J. et al.

Year:

1980

Bibliographic source:

Chemosphere, 9, 231 - 249

Reference 3

Reference Type:

secondary source

Title:

OECD SIDS 2,4-Dichlorotoluene, CAS No. 95-73-8

Author:

OECD

Year:

1995

Bibliographic source:

UNEP Publications

Report date:

1995

Reference 4

Reference Type:

secondary source

Title:

HSDB database: 2,4 - DICHLOROTOLUENE, CASRN: 95-73-8

Author:

US National Library of Medicine

Bibliographic source:

http://toxnet.nlm.nih.gov/...HSDB

Report date:

2009

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

The water from the following areas in The Netherlands was analysed in order to estimate the occurence of 2,4-dichlorotoluene:
a) Surface water of the river Rhine
b) Water in lakes
c) Ground water
The detection limit was reported to be 0.01 µg/L.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

2,4-dichlorotoluene

EC Number:

202-445-8

EC Name:

2,4-dichlorotoluene

Cas Number:

95-73-8

Molecular formula:

C7H6Cl2

IUPAC Name:

2,4-dichloro-1-methylbenzene

Results and discussion

Concentration

Country:

Netherlands (the)

Location:

Lobith - Gorinchem

Substance or metabolite:

substance

Conc.:

0.3 µg/L

Remarks on result:

other: DT50 of 1.0 day (only Zoeteman)

Any other information on results incl. tables

Zoeteman et al. calculated a DT50 of 1.0 days based on a comparison of the concentrations of 2.4-DCT measured at Lobith on the 16 July and Gorinchem on 17 July 1979. The relevant concentration in Lobith on 16 July was 0.3 µ/L.The DT50 of 1 day in the river Rhine compared to the DT50 determined in lake water is explained by Zoeteman by "increased volatilisation and photochemical degradation by water turbulences".

For lake water, the half-lives were found to be at least by a factor 10 higher than in the river Rhine.

In ground water, 2,4-dichlorotoluene was not detected.

Linders et al. reported the results as follows:

Concentration of 2,4-dichlortoluene:

Lobith on 26.02.79: 0.1 µg/L

Maasluis on 01.03.79: no value reported

Lobith on 16.07.79: 0.3 µg/L

Gorinchem on 17.07.79: 0.3 µg/L

Maasluis on 19.07.79: 0.01 µg/L

Lobith on 15.10.79: 0.1 µg/L

Maasluis on 18.10.79: 0.1 µg/L

The results as reported by Linders et al. do not confirm the LD50 for 2,4 -DCT derived by Zoeteman et al.

In the SIDS and in HSDB, only the publication by Zoeteman is cited.

Applicant's summary and conclusion

Executive summary:

Water from the following areas in The Netherlands was analysed in order to estimate the occurence of 2,4-dichlorotoluene:

a) Surface water of the river Rhine in Lobith, Gorinchem and Maasluis. Flow time between Lobith and Gorinchem is generally 24 h and between Lobith an Maassluis 2 - 3 days depending on stream velocity.

b) Water in lakes

c) Ground water

The detection limit was reported to be 0.01 µg/L.

Zoeteman et al. reported the results as follows: for the river Rhine, a DT50 of 1.0 day was estimated for 2,4-dichlorotoluene. This was explained with increased volatilisation and photochemical degradation by water turbulences.

For lake water, the half-lives were found to be at least by a factor of 10 higher than in the river Rhine. In ground water, 2,4-dichlorotoluene was not detected.

Linders et al reported the results in more detail, but these do not confirm the LD50 derived by Zoeteman et al.

The results were cited in the SIDS and in the HSDB data base, but only as reported by Zoeteman et al.

References: Zoeteman, 1980 and Linders, 1981