Triethoxy(3-isocyanatopropyl)silane

Bioaccumulation: aquatic / sediment

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

bioaccumulation in aquatic species: fish

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance has a low potential for bioaccumulation based on log Kow <=3

Reference 2

Endpoint:

bioaccumulation in aquatic species: fish

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1994-10-12 to 1995-02-20

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Radiolabelling:

no

Details on sampling:

IN THE TEST WATER :
Test material was analysed twice weekly, 16 times in total, for both concentration 1 area and 2 area during exposure period, using one sample each time.
IN THE TEST FISH :
Test material was analysed 2, 4, 6, and 8 weeks, 4 times in total for both concentration 1 area and 2 area, after the initiation of exposure, using two fish samples each time. The analysis of test material in the control fish was performed before the start and after the completion of exposure, using two fish samples each time.

Vehicle:

no

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

Concentration 1 area

The test material was dissolved in ion-exchanged water and obtained a 1000 mg/L test material stock solution.

Concentration 2 area
The test material was dissolved in ion-exchanged water and obtained a 100 mg/L test material stock solution.

These stock solutions were put into each 25 L-volume glass stock solution tank and supplied to test aquarium.

Test organisms (species):

Cyprinus carpio

Details on test organisms:

TEST FISH ;
Common name : Common carp
Strain : Carp ( Cyprinus carpio )
Source : Sugishima fish farm

Condition for fish cultivation :
The fishes which receipted at 7 June, 1994 were macroscopically examined on receipt and those demonstrating any abnormalities were removed. Then, the fish were cultivated for 34 days under the condition of flow-through water following an external disinfection in the aquarium in which the fish were received.

Acclimatisation condition :
After the cultivation and dipping for parasite removal, the fish were transferred to an acclimatisation tank and acclimated after further dipping. During acclimatisation period, fish demonstrating any abnormalities were eliminated and the fish were cultivated under the condition of flow-through water at 25±2 ℃ for 54 days. Finally, they were transferred to test tank, dipped and cultivated for 49 days at same temperature under the condition of flow-through water. Terminated date of acclimatisation ; 7 Sep., 1994.
Fish length at study initiation : 9.9 cm on average
Fish weight at study initiation : 26.2 g on average

Feeding ;
Feed : Formula pellet feed for carp ( Nippon Formula Feed Mfg. Co., Ltd. )
Feeding method : An amount corresponding to about 2 % of the test fish bodyweight was fed twice daily in halves. On the day of before sampling, however, feeding was suspended.

Route of exposure:

aqueous

Test type:

flow-through

Water / sediment media type:

natural water: freshwater

Total exposure / uptake duration:

8 wk

Hardness:

Total hardness ( Ca, Mg ) : 127 mg/L ( Sampling date : August 02, 1994 )

Test temperature:

Test temperature ; 25 ± 2 ℃

pH:

7.6 ( Sampling date : August 02, 1994 )

Dissolved oxygen:

Concentration 1 area ; 6.4 - 7.2 mgO2/L
Concentration 2 area ; 6.3 - 7.7 mgO2/L
Control area ; 7.4 - 7.9 mgO2/L

TOC:

Total Organic Carbon ; 0.1 mg/L ( Sampling date : August 02, 1994 )

Salinity:

no data due to freshwater test

Details on test conditions:

TEST SYSTEM ;
(1) Supply of test water : A flow-through water system assembled by this testing facility was used
(2) Test vessel : 100 L glass aquarium
(3) Flow rate of test water : The test material stock solution and the dilution water were supplied to the test aquarium in an amount of 579 L/day in total, at rates of 2 mL/min. of test material stock solution and 400 mL/min. of dilution water, respectively.
(4) Number of test fish used :
Concentration 1 and 2 area ; 11 each test aquarium (at the initiation of exposure)
Control area ; 5 (at the initiation of exposure)

DILUTION WATER FOR TEST ;
(1) Origin : Underground water pumped from the premises of Kurume Research Laboratories
(2) Water quality assessment : The water sample was measured or analysed periodically once per six months following items such as pH, chemical oxygen demand, total hardness, chlorine ion and ammonia nitrogen, together with hazardous substances such as organic phosphorus, cyanide ion, heavy metals etc. in this laboratory. It was confirmed that the values of these analysis parameters of the water for the test were not larger than the concentration value described in the " Water Quality Standards based on Water Works Law " ( Health and Welfare Ministry Ordinance No. 56, amended on Dec. 21, 1992 ), " Water Quality Criteria for Fisheries " ( Japan Marine Resource Protection Association, March 1983 ) or " OECD Guideline for Testing Chemicals 210, Fish, Eaely-life Stage Toxicity Test " .

PRELIMINALY STUDY ;
(1) Test method : The preliminary test was performed in accordance with the method described in " Factory Effluent Test Method : Acute Toxicity Test in Fish " ( 71 of JIS K -102-1993 ).
(2) Species : Killifish ( Oryzias latipes )
(3) Duration of exposure : 48 hours
(4) Exposure method : Semi-static system ( Renewal of test water after 24 hours )
(5) Test result : 48-hr LC50 of test material ; > 1000 mg/L ( The calculation was performed by the Doudoroff method )

RATIONAL OF THE TEST MATERIAL CONCENTRATION FOR DEFINITIVE TEST ;
Based on the preliminary test results for 48-hr LC50 and the analytical sensitivity of test material, the test material concentrations for definitive test were determined as follow ;
Concentration 1 area ; 5 mg/L
Concentration 2 area ; 0.5 mg/L

Nominal and measured concentrations:

Concentration 1 area ; 5 mg/L ( Nominal )
Concentration 2 area ; 0.5 mg/L ( Nominal )

Reference substance (positive control):

no

Details on estimation of bioconcentration:

no description

Lipid content:

4.3 %

Time point:

start of exposure

Remarks on result:

other: average value

Type:

BCF

Value:

3.4 dimensionless

Basis:

whole body w.w.

Calculation basis:

steady state

Remarks on result:

other: Conc.in environment / dose:5 mg/L

Metabolites:

no data

Results with reference substance (positive control):

no use of reference substance

Details on results:

Mortality of test organisms: No deaths were observed during the test period.
Abnormalities of test fish: No abnormalities were observed during the test period.

Table.1: Bioaccumulation factor

Concentration area	2 weeks	4 weeks	6 weeks	8 weeks
Concentration 1 area	less than 3.4 less than 3.4	less than 3.4 less than 3.4	less than 3.4 less than 3.4	less than 3.4 less than 3.4
Concentration 2 area	less than 34 less than 34	less than 34 less than 34	less than 34 less than 34	less than 34 less than 34

Conclusions:

A steady-state BCF value of 3.4 was determined in a reliable study conducted according to an appropriate test protocol, and in compliance with GLP. The test material supplied by the sponsor was easily hydrolysed in aqueous solution and changed in γ-aminopropyltrihydroxysilane. Therefore, it was considered that the actual test material for this study was γ-aminopropyltrihydroxysilane.

Description of key information

Bioaccumulation: aquatic/sediment: Low potential for bioaccumulation

Additional information

The submission substance hydrolyses very rapidly to substances which have low log K_owvalues (<3) and thus have low potential for bioaccumulation, and the requirement for testing is waived. During hydrolysis, the substance forms 3-aminopropyl(triethoxy)silane (CAS 919-30-2) as an intermediate hydrolysis product and carbon dioxide.

A bioaccumulation in fish study was conducted with 3-aminopropyl(triethoxy)silane according to OECD Test Guideline 305C and in compliance with GLP. The test material supplied by the sponsor was easily hydrolysed in aqueous solution forming 3-aminopropyltrihydroxysilane. Therefore, it was considered that the test organism is exposed to the silanol hydrolysis product, 3-aminopropyltrihydroxysilane. A steady-state BCF value of 3.4 was determined for 3-aminopropylsilanetriol.

3-Aminopropyl(triethoxy)silane hydrolyses rapidly to substances (3-aminopropylsilanetriol and ethanol) which have low log K_owvalues (<3) and thus have low potential for bioaccumulation. 3-Aminopropyl(triethoxy)silane also has a log K_owvalue of <3.