Essential Oil of Piper nigrum L. (Family: Piperaceae). Obtained by the steam distillation of dried unripe berries.

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification

Justification for type of information:

The supporting QMRF report has been attached

Qualifier:

according to guideline

Guideline:

other: estimated data

Principles of method if other than guideline:

The prediction was done by using OECD QSAR tool box v3.3

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material: Black Pepper Oil
- IUPAC name: Pepper, black, oil (Piper nigrum L.)
- Molecular formula: Unspecified
- Molecular weight: Unspecified
- Smiles : Unspecified
- Inchl: Unspecified
- Substance type: Organic
- Physical state: Liquid (colorless to slightly greenish)

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)

Test type:

static

Water media type:

freshwater

Total exposure duration:

72 h

Hardness:

150 mg/L as NaHCO3

Test temperature:

23 +/- 2°C

pH:

7.98-8.10 (control and test vessels, start) 8.26-10.04 (control and test vessels, end)

Reference substance (positive control):

not specified

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

0.911 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: other details not available

The prediction was based on dataset comprised from the following descriptors: EC50
Estimation method: Takes average value from the 5 nearest neighbours
Domain  logical expression:Result: In Domain

((("a" or "b" or "c" )  and ("d" and ( not "e") )  )  and ("f" and "g" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Alkene OR Allyl OR Cycloalkene by Organic Functional groups ONLY

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Allyl OR Cycloalkene OR Overlapping groups by Organic Functional groups (nested) ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Aliphatic Carbon [CH] OR Aliphatic Carbon [-CH2-] OR Aliphatic Carbon [-CH3] OR Olefinic carbon [=CH- or =C<] OR Olefinic carbon [=CH2] OR Tertiary Carbon by Organic functional groups (US EPA) ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Non binder, without OH or NH2 group by Estrogen Receptor Binding

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Non binder, non cyclic structure by Estrogen Receptor Binding

Domain logical expression index: "f"

Parametric boundary:The target chemical should have a value of log Kow which is >= 3.19

Domain logical expression index: "g"

Parametric boundary:The target chemical should have a value of log Kow which is <= 4.88

Validity criteria fulfilled:

not specified

Conclusions:

EC50 value of test chemical black pepper oil was estimated to be 0.9112 mg/L when it was exposed to Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) algae for 72 hrs.

Executive summary:

Toxicity of test chemical Black pepper oil (CAS no. 8006-82-4) to aquatic algae Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was estimated by using OECD QSAR tool box v3.3 and by considering five closest read across chemicals. EC 50 value was determined to be 0.9112 mg/L in 72 hrs on the basis of growth rate. By considering EC50 value it is concluded that test chemical Black pepper oil is toxic to Pseudokirchneriella subcapitata and can be classified in aquatic acute 1 category according to CLP classification criteria.

Description of key information

Toxicity of test chemical Black pepper oil (CAS no. 8006-82-4) to aquatic algae Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was estimated by using OECD QSAR tool box v3.3 and by considering five closest read across chemicals. EC 50 value was determined to be 0.9112 mg/L in 72 hrs on the basis of growth rate. By considering EC50 value it is concluded that test chemical Black pepper oil is toxic to Pseudokirchneriella subcapitata and can be classified in aquatic acute 1 category according to CLP classification criteria.

Key value for chemical safety assessment

EC50 for freshwater algae:

0.911 mg/L

Additional information

Results of predicted data for target chemical Black pepper oil (CAS no. 8006-82-4) and experimental data for its read across chemical with log Kow as primary descriptor are summarized below for toxicity of green algae and cyanobacteria endpoint.

In a first predicted data the toxicity of test chemical Black pepper oil (CAS no. 8006-82-4) to aquatic algae Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was estimated by using OECD QSAR tool box v3.3 and by considering five closest read across chemicals. EC 50 value was determined to be 0.9112 mg/L in 72 hrs on the basis of growth rate. By considering EC50 value it is concluded that test chemical Black pepper oil is toxic to Pseudokirchneriella subcapitata and can be classified in aquatic acute 1 category according to CLP classification criteria.

In another predicted data the short-term toxicity of the test substance Black Pepper Oil (CAS no. 8006-82-4) to green algae was predicted using Estimation Program Interface (EPI Suite, 2017) ECOSAR version 1.10. On the basis of effects observed in a static freshwater system during a 96 hr exposure, the effect concentration (EC50) for the substance is estimated to be 0.522 mg/L. Based on this value, it can be concluded that the test chemical Black pepper oil can be considered as toxic to green algae at environmentally relevant concentrations and can be considered to be classified in aquatic acute category 1 as per the CLP classification criteria.

Further, the supporting experimental weight of evidence study was done from authoritative database  J Check (2017) in this study the toxicity of read across chemical methylcyclohexane (CAS no. 108-87-2) was determined on the green algae on the basis of its growth rate for 72 hrs. The EC50 value of read across chemical methylcyclohexane obtained was 0.34 mg/L and NOEC value obtained was 0.067 mg/L on the basis of growth rate of green algae when read across chemical was exposed to green algae for 72 hrs. On the basis of EC50 value it is concluded that this read across chemical can be considered as toxic to green algae and classified in aquatic acute 1 category according CLP classification criteria.

Last study was also experiment study done from Ecotox database (2017) for read across chemical 1-methyl-4(1-methylethylidene) cyclohex-1-ene (CAS no. 586-62-9). In this study the short term toxicity to aquatic algae namely Pseudokirchneriella subcapitata (Green Algae) was determined by exposing it to read across chemical 1-methyl-4(1-methylethylidene) cyclohex-1-ene for 96 hrs. NOEC value was determined to be 0.03-0.95 mg/L on the basis of inhibition of biomass (Population).

On the basis of results of all the studies mentioned above EC 50 value of test chemical Black pepper oil (CAS no. 8006-82-4) was in range of 0.522-0.9112 mg/L and by considering this EC50 value range it is concluded that this test chemical is toxic to aquatic green algae and can be classified in aquatic acute 1 category as per the CLP classification criteria.