Essential oil of Spearmint obtained from the aerial part of Mentha spicata and/or Mentha cardiaca (Lamiaceae) obtained by distillation

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:

20/1/2015 - 27/1/2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Study according to international guideline (OECD guideline 203) under GLP. No deviations from guideline reported.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

Principles of method if other than guideline:

Not relevant

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

spearmint oil
Mentha cardiaca, ext.
EC 294-809-8
CAS 91770-24-0
Oil of spearmint - Chinese type
Oil of spearmint - Scotch variety

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

Analytical monitoring:

yes

Details on sampling:

- Concentrations: nominal WAF of 4.6 mg/l
- Sampling method: 50 ml Samples for possible analysis were taken from all test concentrations and the control according at t=0 h and t=96 h.
Volume 50 ml
- Sample storage conditions before analysis: Samples were stored in a refrigerator until analysis. Additionally, reserve samples of 50 ml were taken from all test solutions for possible analysis. If not already used, these samples were stored in a freezer for a maximum of three months after delivery of the draft report, pending on the decision of the sponsor for additional analysis.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Water Accommodated Fractions (WAFs) were prepared at individual loading rates. Exact amounts of test substance were added to test medium and magnetically stirred for 2 days in closed vessels with minimal headspace. Thereafter, all solutions were left to stabilise overnight. Subsequently, the WAFs were collected by siphoning the water phase. In the limit test two vessels were used for preparation and the WAFs were pooled.
- Controls: yes, blanks

Test organisms (species):

Cyprinus carpio

Details on test organisms:

TEST ORGANISM
- Common name: Carp
- Source: Zodiac, proefacc, "De Haar Vissen", Wageningen University and Research Centre, The Netherlands.
- Length at study initiation (length definition, mean, range and SD): 2.6 ± 0.3 cm
- Weight at study initiation (mean and range, SD): 0.46 ± 0.17 g
- Method of breeding: F1 from a single parent-pair bred in UV-treated water. Fish held in adjusted ISO medium, formulated using RO-water (tap-water purified by reverse osmosis; GEON Waterbehandeling, Berkel-Enschot, The Netherlands)
- Feeding during test: No

ACCLIMATION
- Type and amount of food: pelleted fish food (Cyprico Crumble Excellent (300-500 um), Coppens International bv, Helmond, The Netherlands)
- Feeding frequency: daily
- Health during acclimation (any mortality observed): In the batch of fish used for the test, mortality during the seven days prior to the start of the test was less than 5%.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

No

Hardness:

180 mg/l CaCO3

Test temperature:

21 - 22ºC

pH:

7.5 - 7.8

Dissolved oxygen:

6.8 - 9.4 mg/l

Salinity:

Not relevant

Nominal and measured concentrations:

Nominal: 4.6 mg/l (WAF)
Measured: see Section "Any other information on results".

Details on test conditions:

TEST SYSTEM
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: 6.5 litres, all-glass, containing 6.3 litres of test solution
- Aeration: None
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 0.51 g fish/litre

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Adjusted ISO medium, formulated using RO-water (tap-water purified by reverse osmosis; GEON Waterbehandeling, Berkel-Enschot, The Netherlands)
- Composition:
CaCl2.2H2O 211.5 mg/l
MgSO4.7H2O 88.8 mg/l
NaHCO3 46.7 mg/l
KCl 4.2 mg/l
- Culture medium different from test medium: No
- Intervals of water quality measurement: temperature was measured continuously, pH and oxygen saturation were measured at the start and end of the test.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): mortality (after 2½, 24, 48, 72 and 96 hours)

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 4.6
- Range finding study
- Test concentrations: 1.0, 10 and 100 mg/l (WAF)
- Results used to determine the conditions for the definitive study: Yes

Reference substance (positive control):

yes

Remarks:

Pentachlorophenol

Duration:

24 h

Dose descriptor:

LL50

Effect conc.:

> 4.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

48 h

Dose descriptor:

LL50

Effect conc.:

> 4.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

72 h

Dose descriptor:

LL50

Effect conc.:

> 4.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

> 4.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Mortality of control: 0%
- Observations: No mortality or other clinical effects were observed in the limit test.

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- Mortality: 100%
- 96h-LC50: 0.32 mg/l

Reported statistics and error estimates:

No LL50 could be calculated because the effects observed at the limit concentration were below 50% (LL50 > maximum loading rate tested).

Sublethal observations / clinical signs:

Incidence of mortality and total mortality during the limit test

Spearmint Essential oil, ex Mentha cardiaca Loading rate (mg/l)	Initial number of fish	Cumulative mortality					Total mortality (%)
		2.5h	24h	48h	72h	96h
Control	7	0	0	0	0	0	0
4.6	7	0	0	0	0	0	0

Measured TOC concentrations in the limit test

Spearmint Essential oil, ex Mentha cardiaca Loading rate (mg/l)	Measured concentration (mg TOC/l) t=0h	Measured concentration (mg TOC/l) t=96h	Relative to initial (%)
Control	2.331 4.305^2	0.6457^1	n.a.
4.6	4.579	3.443	75

1. Concentration was below the limit of quantification of the analytical method (<1.0 mg/l) and therefore, should be considered indicative.

2. Reserve sample

n.a. Not applicable

Validity criteria fulfilled:

yes

Remarks:

No mortality in controls, test conditions constant, dissolved oxygen above 60% of air saturation value

Conclusions:

The acute toxicity (96h-LL50) of Spearmint oil (Spearmint Essential oil, ex Mentha cardiaca) towards Cyprinus carpio is > 4.6 mg/l.

Executive summary:

The acute toxicity of Spearmint oil (Spearmint Essential oil, ex Mentha cardiaca) towards Cyprinus carpio was investigated according to OECD guideline 203 under GLP. Fish were exposed to a nominal WAF of 4.6 mg/l and were observed for 96 hours. The 96h-LL50 was found to be > 4.6 mg/l.

Description of key information

96h-LL50: >4.6 mg/l

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

4.6 mg/L

Additional information

The acute toxicity of Spearmint oil (Spearmint Essential oil, ex Mentha cardiaca) towards Cyprinus carpio was investigated according to OECD guideline 203 under GLP. Fish were exposed to a nominal WAF of 4.6 mg/l and were observed for 96 hours. The 96h-LL50 was found to be > 4.6 mg/l.