6,6'-di-tert-butyl-4,4'-butylidenedi-m-cresol

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:

16 July 1980 to 20 July 1980

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study performed following the intent of GLP with recognised standards referenced in the report.

Qualifier:

according to guideline

Guideline:

other: Committee on Methods for Toxicity Tests with Aquatic Organisms (C. E. Stephan, Chairman). 1975. Methods for Acute Toxicity Tests with Fish, Macroinvertebrates and Amphibians. Environmental Protection Agency, Ecological Research Series EPA-660/3-75-009

Qualifier:

according to guideline

Guideline:

other: American Public Health Association. 1975. Standard Methods for the Examination of Water and Wastewater. 14th ed. Washington, DC. 1193 p.

GLP compliance:

yes

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
Not specified

Analytical monitoring:

not specified

Details on sampling:

Based on the results of preliminary testing, five concentrations of the test compound, ranging in a logarithmic series from 100 to 1,000 mg/l.
The test concentrations were obtained by transferring appropriate weights of the sample directly to the test chambers.
The sample was stored at 4°C.

Vehicle:

not specified

Details on test solutions:

Test concentrations were prepared based on the total compound. Before the test concentrations were prepared, the standard was allowed to warm to room temperature (22°C). The test concentrations were obtained by transferring appropriate weights of the sample directly to the test chambers. The compound was noted to precipitate in all test solutions .

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

The rainbow trout used in the test were obtained from Trout Lodge in McMillan, Washington. The fish were identified to species using the taxonomic keys developed by Eddy. All test fish were held in culture tanks on a 16 hour daylight photoperiod and observed for at least fourteen days prior to testing. Fish culture techniques used were basically those described by Brauhn et. al. A daily record of fish observations during the holding period, along with prophylactic and therapeutic disease treatments. During this period, the fish received a standard commercial fish food (Rangen's) daily until 48 hours prior to testing at which time feeding was discontinued. The rainbow trout used for this experiment had a mean weight of 0.35 g and a mean standard length of 29 mm. Weight and length measurements were made on the control group of fish at the termination of the test.
The test fish were acclimated to the dilution water and test temperature and held without food 48 hours prior to testing.

Test type:

static

Water media type:

brackish water

Total exposure duration:

96 h

Post exposure observation period:

No post exposure observation period specified in the report

Hardness:

255ppm

Test temperature:

12°C

pH:

8.2

Dissolved oxygen:

9.3ppm

Salinity:

Not specified

Nominal and measured concentrations:

Measured concentrations

Details on test conditions:

The static fish bioassay was conducted in five gallon glass vessels containing 15 litres of laboratory well water. These vessels were kept in a water bath at 12°C (±1.0). The test fish were acclimated to the dilution water and test temperature and held without food 48 hours prior to testing.
A 48 hour range-finding test was conducted to determine the concentration range for the definitive study. The preliminary test concentrations were set at 1,10 and 100 mg/l. Based on the results of preliminary testing, five concentrations of the test compound, ranging in a logarithmic series from 100 to 1,000 mg/l, with ten fish per concentration were selected for definitive bioassay, as approved by the study sponsor. The fish were added to the test chambers by random assignment within 30 minutes after addition of toxicant aliquots.

Reference substance (positive control):

yes

Remarks:

Antimyin A

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% C.I.

Details on results:

The dissolved oxygen concentration which stayed between 60 and 100% saturation was considered adequate for testing. The pH values remained consistent with the control throughout the study. The ammonia concentrations were below the toxic limit.

Results with reference substance (positive control):

As a quality check, the rainbow trout were challenged with a reference compound, Antimycin A. The observed 96 hour LCs0 and 95% confidence limits (C.I.) were within the 95% confidence limits reported in the literature, indicating that the fish were in good condition.

Reported statistics and error estimates:

Not specified

Sublethal observations / clinical signs:

The Acute Toxicity of Santowhite Powder and Antimycin A to Rainbow Trout (Salmo gairdneri)*

	LC50 in milligrams/litre (ppm)
Compound	24 hours	48 hours	96 hours
Santowhite powder	>1,000	>1,000	>1,000
Antimycin A	0.000060 (0.000042 – 0.000075)**	0.000028 (0.000023 – 0.000036)	0.000019 (0.000016 – 0.000024)

*Bioassay as conducted as 12°C (±1.0), mean weight and length, 0.35g and 29mm.

**95% confidence interval.

***Antimycin A standard obtained from Sigma Chemical Company, Type III, crystalline, Lot 125C – 0152.

 

Mortality Rates and Water Quality Measurements During the Acute Toxicity Test of Santowhite Powder to Rainbow Trout (Salmo gairdneri)

				Water Quality
	Percent Mortality Hours			0 hours				48 hours				96 hours
mg/l Concentration	24	48	96	Temp.°C	D.O.* mg/l	pH**	NH3*** mg/l	Temp.°C	D.O.* mg/l	pH**	NH3*** mg/l	Temp.°C	D.O.* mg/l	pH**	NH3*** mg/l
Control	0	0	0	12	8.3	7.6	0.18	12	8.0	7.6	0.30	12	8.5	7.7	0.26
100	0	0	0	12	8.7	7.5	0.20	12	8.5	7.7	0.26	12	7.7	7.8	0.18
180	0	0	0
320	0	0	0
560	0	0	0
1,000	0	0	0	12	8.9	7.5	0.21	12	8.3	7.7	0.24	12	7.5	7.7	0.20

*Dissolved oxygen concentrations – Dissolved Oxygen Probe (YSI Model 54).

**pH – pH Probe (Orion Model 91 – 06) used with an Extech Model 671 pH and mV meter.

***Total ammonia concentrations – ammonia Probe (Extech Model 8002 – 8) used with an Extech Model 671 pH and mV meter.

Conclusions:

96 hour LC50 >1,000 mg/l

Executive summary:

The acute toxicity of Santowhite Powder to rainbow trout (Salmo gairdneri) was assessed using the methods outlined by the Committee on Methods for Toxicity Tests with Aquatic Organisms. Water quality parameters of temperature, dissolved oxygen, pH and ammonia were measured throughout the test and were within acceptable limits. The study was conducted following the intent of the Good Laboratory Practice Regulations.

As a quality check, the rainbow trout were challenged with a reference compound, AntimycinA.The observed 96 hour LCs0 and 95% confidence limits (C.I.) were within the 95% confidence limits reported in the literature, indicating that the fish were in good condition.

The results of the four day static fish toxicity study using rainbow trout are summarized below:

 

Compound: Santowhite powder, 96 hour LC50 >1,000 mg/l

Compound: Antimycin A, 96 hour LC50 0.000019

Description of key information

Key value determined using US EPA and American Public Health Association guidance.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

1 000 mg/L

Additional information

Both the supporting studies provide the same result as the key value described.