Valeric anhydride

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Dec 2002 - Jan 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Principles of method if other than guideline:

Not relevant

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Daphnia magna

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Table 1: Cumulative immobilization (%) of Daphnia magna (n=20) after exposure to

ZK 56407/ ZK 56510

Concentration of ZK 56407 / ZK 56510 (mg/L)	24 hours	48 hours
0 control (tap water)	0	5
100	0	5

Validity criteria fulfilled:

yes

Conclusions:

The ECso/48 hours of hydrolysed ZK 56407 (valeric anhydride) to Daphnia magna is expected to
be higher than 100 mg/L.

Executive summary:

The purpose ofthe study was to detennine the acute toxicity (immobilization, ECso/48 hours) of Valeriansäureanhydrid (ZK 56407) with Daphnia magna in order to evaluate the aquatic toxicity. ZK 56407 is an intermediate of the synthesis of different steroids.

The study was conducted as a limit test according to the following guidelines ofthe OECD, no 202.

20 juvenile Daphnia magna were used for the test solution of ZK 56407 and 20 for the tap water

control. The Daphnia were exposed for aperiod of 48 hours under static conditions.

Immobilization was recorded at 24 hours and 48 hours.

For the preparation of the test solution, a suspension with a nominal loading of approximately 100 mg/L was ultrasonified for approximately 30 minutes and stirred for approximately 24 hours. This suspension was filtered through a glassfibre filter. The solution obtained by this procedure was used for the preparation of the test solution. ZK 56407 (valeric anhydride)

hydrolyses rapidly into valeric acid (ZK 56510), which is weIl soluble.

Therefore, it is expected that the test solution contained almost entirely valeric acid.

The organic carbon concentration ofthe test solution was analyzed with a TOC analyzer in

sampIes taken at the start of exposure and 48 hours thereafter. The substance concentration was

calculated on the basis of the molecular fonnula. The mean concentration was calculated with

102.75 mg/L [valeric acid (ZK 56510)] which indicated complete solubility, In the following, the

results are interpreted in the context of the nominal concentration of 100 mg/L.

The EC50/48 hours of hydrolysed ZK 56407 (valeric anhydride) to Daphnia magna is expected to be higher than 100 mg/L.

Description of key information

The ECso/48 hours of hydrolysed ZK 56407 (valeric anhydride) to Daphnia magna is expected to

be higher than 100 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L