2-chlorotoluene

Bioaccumulation: aquatic / sediment

Link to relevant study record(s)

Reference

Endpoint:

bioaccumulation in aquatic species: fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

January 17, 1979 - March 31, 1979

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

According to older guideline version, limited reporting

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 305 C (Bioaccumulation: Test for the Degree of Bioconcentration in Fish)

Version / remarks:

1981

Qualifier:

according to guideline

Guideline:

other: "Bioaccumulation test of chemical substance in fish and shellfish", order of the prime minister, the minister of health and welfare, the minister of international trade and industry No 1, Japan, 1974

Principles of method if other than guideline:

This guideline corresponds to OECD Guideline 305C (Bioaccumulation: Test for the degree of bioconcentration in Fish), 1981

GLP compliance:

not specified

Radiolabelling:

no

Details on sampling:

- Sampling intervals/frequency for test organisms: every two weeks, n=2 fish per treatment concentration and observation point; control fish analysis: before the initiation and after the termination of exposure, n=2
- Sampling intervals/frequency for test medium samples: twice a week, n=1

Vehicle:

yes

Remarks:

HCO-40: 1.5 ppm (w/v) for concentration level 0.3 ppm (w/v); 0.15 ppm (w/v) for concentration level 0.03 ppm (w/v);

Details on preparation of test solutions, spiked fish food or sediment:

It is necessary to prepare a solution of the test substance 100 times highly concentrated than that in the aquarium. If the test substance is not soluble enough in water, suitable solubilisers were used. More detailled information is not available for the substance tested .

Test organisms (species):

Cyprinus carpio

Details on test organisms:

Supplier: Sugishima fish farm, Japan
Weight: about 30g, Length: about 10 cm, Lipid content: 2-6 % (at the initiation of exposure)

Route of exposure:

aqueous

Test type:

flow-through

Water / sediment media type:

natural water: freshwater

Total exposure / uptake duration:

8 wk

Test temperature:

25+-2°C

Dissolved oxygen:

6-8 mg/L

Details on test conditions:

Test tank: 100L glass tank
Number of fish: 15-20 fish/Level
Renewal rate of test solutions: flow rate 200-800 mL/min

Nominal and measured concentrations:

Considering of the result of preliminary test for 48-hr LC50 and analytical detecting limit of the test substance, test item concentrations were decided.
Nominal test item concentrations: 0.3 mg/L and 0.03 mg/L.

Measured concentrations determined after 2, 4, 6, and 8 weeks (flow through):
- for nominal 0.3 mg/L: 0.252, 0.283, 0.281, and 0.277 mg/L;
- for nominal 0.03 mg/L: 0.0283, 0.0276, 0.0285, and 0.0274 mg/L

Details on estimation of bioconcentration:

BCF=Cf/Cw with Cf being the concentration determined in fish and Cw being the mean measured water concentration up to the time of sampling. The BCF is the maximum value during the test duration of 8 weeks.

Temperature: 25 °C
Tissue analysed: whole body
Uptake phase duration: 56 days
Flow-through, Freshwater

Lipid content:

ca. 4.3 %

Time point:

start of exposure

Conc. / dose:

0.3 mg/L

Temp.:

25 °C

Type:

BCF

Value:

>= 41.6 - <= 87.2 L/kg

Basis:

whole body w.w.

Time of plateau:

4 wk

Calculation basis:

steady state

Key result

Conc. / dose:

0.03 mg/L

Temp.:

25 °C

Type:

BCF

Value:

>= 20 - <= 112 L/kg

Basis:

whole body w.w.

Time of plateau:

4 wk

Calculation basis:

steady state

Remarks on result:

other:

Details on results:

A detailed results table is given in the attached illustration.

Calculation of bioconcentration factor

BCF = concentration of test substance in fish/concentration of test substance in water

Validity criteria fulfilled:

not specified

Conclusions:

2-Chlorotoluene proved to be of low bioconcentration potential (BCF 87.2 to 112 L/kg whole body wet-weight) in fresh water fish (carp) for the two tested concentrations of 0.3 mg/L and 0.03 mg/L (flow-through), respectively (METI Japan, 1979).

Executive summary:

In a reliable bioconcentration study owned by the Ministry of Economy, Trade and Industry (METI) Japan using carp (Cyrinus carpio), bioconcentration was assessed over 8 weeks at two exposure concentration in flow-through design. The study was performed equivalent to OECD TG 305C (1981) in 1979. Test item concentrations in water were analysed after 2, 4, 6 and 8 weeks and proved to be close to nominal values (0.03 and 0.3 mg/L). After 2, 4, 6, and 8 weeks 2 fish per concentration level were analysed and BCF-values were determined individually from the concentration found in fish and the measured aquatic exposure concentrations. The BCF range reported per exposure level equals the lowest and highest BCF from the eight individual values determined over the course of the test. Both, at the lower and at the higher exposure concentration the plateau was determined after ca. 4 weeks (low variation of BCF values over time).
Results:
BCF at 0.03 mg/L 2-chlorotoluene: 18 - 112 L/kg whole body wet weight;
BCF at 0.3 mg/L 2-chlorotoluene: 42 - 87 L/kg whole body wet weight;
Final conclusion: The BCF determined at steady state for 2-chlorotoluene ranges from 87 to 112 L/kg fish whole body wet weight.

Description of key information

2-Chlorotoluene proved to be of low bioconcentration potential (BCF 87.2 to 112 L/kg whole body wet-weight) in fresh water fish (carp) for the two tested concentrations of 0.3 mg/L and 0.03 mg/L (flow-through), respectively (METI Japan, 1979). The data allow concluding with high confidence that 2-chlorotoluene is not bioaccumulative (not B).

Key value for chemical safety assessment

BCF (aquatic species):

112 L/kg ww

Additional information

In a reliable bioconcentration study owned by the Ministry of Economy, Trade and Industry (METI) Japan using carp (Cyrinus carpio), bioconcentration was assessed over 8 weeks at two exposure concentration in flow-through design. The study was performed equivalent to OECD TG 305C (1981) in 1979. Test item concentrations in water were analysed after 2, 4, 6 and 8 weeks and proved to be close to nominal values (0.03 and 0.3 mg/L). After 2, 4, 6, and 8 weeks 2 fish per concentration level were analysed and BCF-values were determined individually from the concentration found in fish and the measured aquatic exposure concentrations. The BCF range reported per exposure level equals the lowest and highest BCF from the eight individual values determined over the course of the test. Both, at the lower and at the higher exposure concentration the plateau was determined after ca. 4 weeks (low variation of BCF values over time).
Results:
BCF at 0.03 mg/L 2-chlorotoluene: 18 - 112 L/kg whole body wet weight;
BCF at 0.3 mg/L 2-chlorotoluene: 42 - 87 L/kg whole body wet weight;
Final conclusion: The BCF determined at steady state for 2-chlorotoluene ranges from 87 to 112 L/kg fish whole body wet weight.