Pentane, 1,5-diisocyanato-

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Monitoring analysis was performed using TOC. No substance specific method was used.

Qualifier:

according to guideline

Guideline:

other: (HJ/T 153-2004), "The Guidelines for the Testing of Chemicals, Effects on Biotoc Systems" (the 2nd edition) (2013)

Deviations:

no

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

The fish species in the test in not one of the recommended species in the OECD guideline 203

Principles of method if other than guideline:

Preparation of the test solutions method deviated from protocol. According to protocol, W AFs
(Water accommodated fractions) method will be adopted in the limit test, however, it was found
that the test solution clarified and transparent with the test substance stirring 30 min in water.
According to the information provided by sponsor, the test substance is insoluble and hydrolyzed
in water quickly, and the hydrolyzate is soluble in water. Thus, test solutions were prepared by
directly dissolving appropriate amount of test substance in dilution medium and then facilitating
its dispersion by stirring for 30 min in the limit test. The deviation did not affect the accuracy and
scientificity for the test results.

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

During the main test at 0, 24, 48, 72 and 96 h

Vehicle:

no

Details on test solutions:

Preparation of the Test Solutions
In the test, test solutions were prepared by directly dissolving appropriate amount of test
substance in dilution medium and then facilitating its dispersion by stirring for 30 min. The test
solution was clear and transparent. In the limit test, a volume of 9L test solutions obtained was
the evenly distributed to 3 test tanks.

Test organisms (species):

other: Gobiocypris rarus (rare minnow)

Details on test organisms:

The Rare minnow, Gobiocypris rarus, was used in the test on the basis of such important
practical criteria as, for example, their ready availability throughout the year, ease of maintenance,
convenience for testing and any relevant economic, biological or ecological factors. The test
species of Rare minnow, Gobiocypris rarus (Batch No.: F201701I 5G), were bred by our own lab.
A population of a single stock was used in the test.

(1) Holding offish
Fish to be used in the test were held for at least 7 days in water of the quality and temperature to
be used in the test.
A photoperiod of 12 hours light, provided by overhead fluorescent tubes, and 12 hours dark was
maintained. The oxygen concentration was varied from 86 % to 93 % of the air saturation. And
the temperature was controlled between 22.8°C and 23.2°C, pH: 7.65-7.74.
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. The ingredients of the
fish food are given as follows:
Crude Protein> 30.0%
Crude Fat> 2.0%
Crude Fibre< 3.0%
Crude Ash< 12.0%
Moisture < I 0.0%
Characteristics of the fish food are measured at least twice a year by Jiangsu Provincial Center for
Disease Prevention and Control. The latest measuring result is showed in Table 11.
(2) Criteria of fish selection
During the holding period the tanks was inspected daily and any debris or unhealthy or dead fish
removed.
After the 48 hour settling-in period, no mortality was observed in the following 7 days. So the
batch of fish (Batch No.: F201701I5G) was accepted.
The average wet-weight and length of the fish used in the definitive test was 0.223 g and 2.44 cm,
with relative standard deviation (RSD) of 4.71% and 4.47%, respectively

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

145 mg(CaC03)/L

Test temperature:

23°C

pH:

between 7.79 and 7.89

Dissolved oxygen:

77-95% of air saturation

Nominal and measured concentrations:

Measured concentrations according to TOC

Details on test conditions:

TEST SYSTEM
- Renewal rate of test solution (frequency/flow rate): each 24 hours
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3

OTHER TEST CONDITIONS
- Photoperiod: 12 hours photoperiod daily
- At 24, 48, 72 and 96 h, the mortalities of the fish were recorded, and observations on individual
behaviour were performed. Meanwhile, measurements of pH, dissolved oxygen and temperature
were can-ied out and recorded dai ly.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate, K2Cr20 7, CAS: 7778-50-9; Purity: ::'.:': 99.8%; Lot number: L VC0052; Beijing Leon Technology Co. Ltd.

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

100 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

element (dissolved fraction)

Basis for effect:

mortality (fish)

Sublethal observations / clinical signs:

Mortality during main test:

Nominal conc. (mg/L	Measured conc. (mg/L	Initial # of fish	Number of dead fish
blank control	nd	7	24h 0	48h 0	72h 0	96h 0
blank control	nd	7	0	0	0	0
blank control	nd	7	0	0	0	0

100	93.9	7	24h 0	48h 0	72h 0	96h 0
100	93.9	7	0	0	0	0
100	93.9	7	0	0	0	0

Validity criteria fulfilled:

yes

Remarks:

1 Control group was placed into test water alone. 2 Reference substance test K2Cr20 7 resulting 24 h-LC50 of 282 mg/L. 3 pH values of the test media were between 7.79 and 7.89, the Dissolved Oxygenvaried from 77 % to 95 % of the air saturation

Conclusions:

The results showed that under valid semi-static conditions (24 h renewal), the 96 h-LC50 of test
substance to fish (Rare minnow, Gobiocypris rarus) was greater than the nominal concentration
of 100 mg/L (mean measured concentration 93.9 mg/L), while the maximum concentration
causing no mortality (96 h-LC0) was equal to the nominal concentration of 100 mg/L (mean
measured concentration 93.9 mg/L). i.e.:
96 h-LCso > 100 mg/L (mean measured concentration 93 .9 mg/L);
96 h-LCo = 100 mg/L (mean measured concentration 93.9 mg/L).

Executive summary:

Under semi-static conditions (24 h renewal), the acute toxicity of the test substance of POI to

Rare minnow (Gobiocypris rarus) was conducted according to: "The guidelines for the testing of

chemicals" (HJ/T 153-2004), "The Guidelines for the Testing of Chemicals, Effects on Biotoc

Systems" (the 2nd edition) (2013); and with reference to Procedure 203 of the "Guidelines for

Testing of Chemicals" of the OECD: "Fish, Acute Toxicity Test" ( 1992).

According to the information provided by sponsor, the test substance is insoluble and hydrolyzed

in water quickly. Since there is no standard of hydrolyzate, UPLC or GC cannot be used to

determine the hydrolyzate's concentration in water accurately. While TOC method can accurately

detect the concentration of the test substance in test water, and characterize the stability of the test

substance.

A range-finding test with several concentrations was performed (1.0, 10.0 and 100 mg/L nominal).

Semi-static conditions (24 h renewal) method was adopted in limit test. Based on the results of

the range-finding test, the concentration of 100 mg/L was assigned in limit test. For each test tank

3 L test solution was filled in. 3 replicate was assigned for each treatment group and control

group, while the initial number of testing fish was 7 for each group.

The test fish were randomly chosen and put in appropriate test solutions after the temperature has

been adjusted to the required value. This was done in 30 min.

During the test period, the pH values of the control mediums and test mediums were between

7.79 and 7.89, the Dissolved Oxygen (DO) values varied from 77 % to 95 % of the air saturation

at the test temperature; the total hardness was in the range of 155 mg (CaC03)/L to 162 mg

(CaC03)/L; the temperature of the test mediums was maintained in the range of 23.0 °C to 23.2

°C and all fishes in the control group were normal. With the same conditions, K2Cr20 7 was used

as the positive control substance, and the resulting 24 h-LCso was 282 mg/L.

During the test period, all fish in the control groups and treated groups were alive and appeared

normal. The results showed that under valid semi-static conditions (24 h renewal), the 96 h-LC50

of test substance to fish (Rare minnow, Gobiocypris rarus) was greater than the nominal

concentration of 100 mg/L (mean measured concentration 93 .9 mg/L), while the maximum

concentration causing no mortality (96 h-LC0) was equal to the nominal concentration of I 00

mg/L (mean measured concentration 93.9 mg/L). i.e.:

96 h-LC50 > 100 mg/L (mean measured concentration 93.9 mg/L);

96 h-LC0 = 100 mg/L (mean measured concentration 93.9 mg/L).

Description of key information

The results showed that under valid semi-static conditions (24 h renewal), the 96 h-LC50 of test substance to fish (Rare minnow, Gobiocypris rarus) was greater than the nominal concentration of 100 mg/L (mean measured concentration 93.9 mg/L), while the maximum concentration

causing no mortality (96 h-LC0) was equal to the nominal concentration of 100 mg/L (mean measured concentration 93.9 mg/L). i.e.:

96 h-LCso > 100 mg/L (mean measured concentration 93 .9 mg/L);

96 h-LCo = 100 mg/L (mean measured concentration 93.9 mg/L). (Wu 2017)

The 96h-LC0 for 1,6 -diisocyanatohexane (CAS 822-06-0) which is a similar substance as Pentane, 1,5 - diisocyanato was

found to be > 82.8 mg/L (Caspers, 2000)

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

100 mg/L

Additional information

"Should read: > 100 mg/L"