4-chloro-3,5-xylenol

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:

1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

pcmx powder, organic, dissolved in 50% dechlorinated mains water for 12 hours with stirrer.

Vehicle:

yes

Details on test solutions:

50% PCMX solution with 50% dechlorinated tap water mix.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

The sizes of the animals were found to be in approximately normal (Gaussian) distribution.

Test type:

semi-static

Water media type:

other: dechlorinated

Limit test:

yes

Total exposure duration:

96 h

Remarks on exposure duration:

The tests are observed at regular intervals for the first six hours and thereafter at regular intervals for the test duration of four days (96 hours). The mortalities are recorded and any obvious sign of unusual behaviour or stress is noted.

Post exposure observation period:

Test is discontinued after 96 hours.

Hardness:

240mg/L Calcium carbonate per litre.

Test temperature:

mean 14.98 C

pH:

mean pH 8.14

Dissolved oxygen:

overall mean value 94.4% of air saturation value

Salinity:

n/a

Conductivity:

n/a

Nominal and measured concentrations:

0.32 - 10.0 mg/L

Reference substance (positive control):

not specified

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

ca. 1.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 1.4mg/L PCMX, half of trout would survive for 4 days.

Details on results:

The results of this experiment indicate that under these test conditions concentrations of 1.8mg/L PCMX or higher were rapidly toxic to the Rainbow Trout and caused 100% mortality within 24hrs. The maximum concentration to cause no mortality within the test period was 1.0mg/L.
It was noted that although the seven remaining trout in the test concentration of 1.3mg/L, and the 10 exposed to 1.0mg/L PCMX survived the 4 day test period, they were extremely distressed.

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- Mortality: 100% above above 1.8mg/L after 24hrs.
- LC50: 1.4mg/L
- Other:

Reported statistics and error estimates:

The observed mortality at 0.32mg/L is considered anomalous.

Validity criteria fulfilled:

yes

Conclusions:

96h LC50 1.4mg/L

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

1.4 mg/L