α,α,α',α'-tetramethyl-m-xylene-α,α'-diol

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

- Said to be according to OECD guideline 1981, while the latest one is from 1996. - Adult fish were used and no information is given on sexes. - No chemical analysis on test substance in fish feed performed. - Not all detailed raw data available of chemical analyses.

Qualifier:

according to guideline

Guideline:

OECD Guideline 305 B (Bioaccumulation: Semi-static Fish Test)

Deviations:

yes

Remarks:

see Principles of method if other than guideline

Qualifier:

according to guideline

Guideline:

EU Method C.13 (Bioconcentration: Flow-through fish test)

Deviations:

yes

Remarks:

see Principles of method if other than guideline

Principles of method if other than guideline:

- Said to be according to OECD guideline 1981, while the latest one is from 1996. - Adult fish were used and no information is given on sexes. - No chemical analysis on test substance in fish feed performed. - Not all detailed raw data available of chemical analyses.

GLP compliance:

yes

Remarks:

GLP issued by State Environmental Protection Administration (SEPA) of the People’s Republic of China

Radiolabelling:

no

Details on sampling:

- Fish and water sampling schedule
Sample water from the test chambers for the determination of test substance concentration before addition of the fish and during uptake phases. As a minimum, sample the water at the same time as the fish and before feeding.

- Sampling and sample treatment
Obtain water samples for analysis e.g. by siphoning through inert tubing from a central point in the test chamber. Remove 7 fish from the test chambers at each sampling time. Rinse the sampled fish quickly with water, blot "dry", kill instantly, using the most appropriate and humane method, and then weigh.
Treatment of extraction and concentration for the fish samples: seven fish and some anhydrous sodium sulfate were put in the mortar and whetted. Add 50.0 mL Methanol to the samples, shaking 1 hour (200 rpm, 20 °C). After filtering, the residues were added with 50.0 mL Methanol, shaking 1 hour (200 rpm, 20 °C). The combined upper organic phases were dried with rotary evaporator, and then redissolved with 10.0 mL Methanol-water (40:60). The final solution was injected to UPLC-PDA after being filtered.

A sample of seven fish was taken each day parallelly after 0, 3, 7, 10, 14, 21, 28 days, i.e. seven fish altogether. Therefore, 7 concentration values of water sample and fish sample were obtained and then 7 BCF values were calculated.
Treatment of extraction and concentration for the water sample: 5.00 mL water sample was diluted to 10.0 mL with Methanol and then filtered with 0.22 μm millipore membrane. The final solutions were analyzed by the UPLC-PDA described as following.

Vehicle:

no

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

The test solutions were prepared by directly dissolving appropriate amount of test substance in dilution medium through mixing or stirring and then facilitating its dispersion by ultrasonication for 20 min.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

The test adopted zebra fish (Brachydanio rerio) (Batch No: F20111015) were obtained from a commercial fish supplier of Guangzhou Hongfa Aquatic Animals Culture Company in China. Their average body length was 3.0±0.5 cm (including the length of their tail). And average body wet- weight was 0.30± 0.1g.
Acclimate the stock population of fish for 15 days in water at the test temperature and feed throughout on a sufficient diet and of the same type to be used during the test.
The fish was fed daily during the holding period on proprietary fish food. They were held without food for approximately 24 hours before being placed into the test vessels.
Following a 48-hour settling-in period, no fish was dead in the holding time of 7 d. The fish used in tests were free from observable diseases and abnormalities. Fish was not received any treatment for disease in the two weeks preceding the test, and during the test.

The fish food (Batch No: E20110805) was supplied by shanghai baoYe Co., Ltd.
The ingredients of the fish food are given as follows: Crude Protein >49.0%, Crude Fat > 5.0%, Crude Fibre < 3.0%, Crude Ash < 12.0%, Moisture < 10.0%.

During the acclimation and test periods, feed an appropriate diet of known lipid and total protein content to the fish in an amount sufficient to keep them in a healthy condition and to maintain body weight. Feed daily throughout the acclimation and test periods at a level of approximately 1 to 2% of body weight per day. Siphon uneaten food and faeces daily from the test chambers shortly after feeding (30 minutes to 1 hour).

Route of exposure:

aqueous

Test type:

semi-static

Water / sediment media type:

natural water: freshwater

Total exposure / uptake duration:

28 d

Hardness:

140-141 mg/L (as CaCO3)

Test temperature:

23.1 to 23.5 °C

pH:

7.24 to 7.28

Dissolved oxygen:

> 90%

Details on test conditions:

TEST SYSTEM
- Test vessel: tanks made of glass with a capacity of approximately twenty five liters were employed
- Aeration: no
- Renewal rate of test solution (frequency/flow rate): 48h
- No. of organisms per vessel: 70
- No. of vessels per concentration (replicates): 1
- Biomass loading rate: 1.0 g of fish (wet weight) per litre of water.

TEST MEDIUM / WATER PARAMETERS
Good quality tap water which had been dechlorinated for at least 24 hours was used as holding water. The test species can survive, grow and reproduce in the holding water and no abnormal appearance or behaviour appeared.
The water for diluting has the same source.

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hours photoperiod daily
- Light intensity: 1000 lux to 1500 lux

Nominal and measured concentrations:

Nominal: 1, 10 mg/L

Reference substance (positive control):

not specified

Type:

BCF

Value:

other: < 1 to 3.99

Basis:

whole body w.w.

Time of plateau:

14 d

Calculation basis:

steady state

Remarks on result:

other: Time of plateau estimated from table on results

Remarks:

Conc.in environment / dose:1 mg/L

Type:

BCF

Value:

other: < 1 to 2.08

Basis:

whole body w.w.

Time of plateau:

3 d

Calculation basis:

steady state

Remarks on result:

other: Time of plateau estimated from table on results

Remarks:

Conc.in environment / dose:10 mg/L

Details on results:

As the calculated BCF is very low no depuration phase was performed in the study.

Validity criteria fulfilled:

yes

Conclusions:

The study was performed under Chinese GLP. The study can be used for risk assessment and classification and labelling, with some restrictions.

Executive summary:

According to “The guidelines for the testing of chemicals” (HJ/T 153 -2004) and with reference to Procedure 106 of the“Guidelines for Testing of Chemicals” of the OECD: “Bioconcentration: Semi-static Fish Test ”(OECD TG 305B), the bioconcentration factor (BCFs) of the substance (meta-Diisopropanolbenzene) in fish (Brachydanio rerio) was tested.

The bioconcentration test was performed using zebrafish. The test fish were exposed to the concentrations of the test substance with 1 and 10 mg/L under semi-static conditions with 48h renewal. BCF values were measured following 28-day exposure period.

The water sample of the test substance was analyzed emplying UPLC-PDA. The retention time of it was approximate 2.65 min.The linear regression equation of meta-Diisopropanolbenzene was: y = 47326.5 x - 174.1, with good linearity of r²=0.99996 for 0.20~10.0 mg/L.

The fish sample of the test substance was analyzed emplying UPLC-PDA. The retention time of it was approximate 2.950 min.The linear regression equation of meta-Diisopropanolbenzene was: y = 9505.2 x - 1190.9, with good linearity of r²=0.99996 for 1.0~50.0 mg/kg.

The recovery in the water sample was between 92.1%~93.1% and RSD was 3.18%~ 3.78%, when the added concentration of the test substance is 1.00~10.0 mg/L in water samples. The recovery in the fish sample was between 94.6%~99.8% and RSD was 0.67%~4.99%, while the added concentration of the test substance is 1~10 mg/kg in fish samples. The minimum detection amount of PDA detector for meta-Diisopropanolbenzene is1.0×10 ^-9 g, and the minimum detection concentration for water and fish sample is 0.20 mg/L and 1.0 mg/kg.

The results show that the BCF value of meta-Diisopropanolbenzene is < 1~3.99 (at 1 mg/L) and < 1~2.08 (at 10 mg/L).The bioconcentrationfactor of meta-Diisopropanolbenzene in fish was below 100, so the test substance has low bioconcentration effect on fish during the exposure period of 28 days.

Description of key information

The results show that the BCF value of meta-Diisopropanolbenzene is < 1~3.99 (at 1 mg/L) and < 1~2.08 (at 10 mg/L). The bioconcentration factor of meta-Diisopropanolbenzene in fish was below 100, so the test substance has low bioconcentration effect on fish during the exposure period of 28 days.