Gum turpentine oil, consisting of the volatile fraction resulting from the distillation of oleoresin collected by tapping softwoods from pinacea derivatives (genus: pinus). It consists of terpenes, mainly monoterpenes such as alpha-pinene and beta-pinene.

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

23 September 2016 to 16 November 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

GLP study performed according to OECD Guideline No. 301 D. All validity criteria were fulfilled

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 301 D (Ready Biodegradability: Closed Bottle Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test)

Deviations:

no

Principles of method if other than guideline:

Not applicable.

GLP compliance:

yes (incl. QA statement)

Remarks:

signed on 10 of January 2017

Oxygen conditions:

aerobic

Inoculum or test system:

other: river water

Details on inoculum:

- Origin: River water was sampled from “La Mourachonne”, situated downstream of a plant treating domestic wastewater (Pegomas, France).
- Pre-conditioning: The river water was aerated for about 7 days before use as inoculum at the test temperature to reduce endogenous respiration.

Duration of test (contact time):

28 d

Initial conc.:

2 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Test water: Mineral medium, Reconstituted water, as prescribed by the OECD Guideline No. 301D
- Composition of medium: Mineral medium (8.5 mg KH2PO4, 21.75 mg K2HPO4, 33.40 mg Na2HPO4•2H2O, 0.50 mg NH4Cl; 36.40 mg CaCl2•2H2O, 22.50 mg MgSO4•7H2O and 0.25 mg FeCl3•6H2O.)
- River water was aerated for about 7 days before use as inoculum at the test temperature to reduce endogenous respiration.
- Test temperature: Temperatures recorded continuously were situated between 20.2 and 21.5°C throughout the test (average value: 21.2°C)
- Continuous darkness: Yes

TEST SYSTEM
- Culturing apparatus: All-glass sealed with ground glass stoppers BOD (Biological Oxygen Demand) bottles of approximately 300 mL capacity.
- Inoculum: A concentration of inoculum of approximately 10^5 cells/L was used.
- Number of culture flasks/concentration: 10 bottles containing test item, inoculum, mineral medium and silica gel (test suspension)

SAMPLING
- Sampling frequency: Determinations of the concentration of dissolved oxygen using an oxygen electrode in duplicate vessels taken from each group (except the procedure control) were made at day 0, 7, 14, 21 and 28, and only at the start of the test and after 7 and 14 days of incubation for the procedure control.
- Temperature: Measured continuously in the growth chamber.

CONTROL AND BLANK SYSTEM
- Inoculum blank: 10 bottles containing inoculum, mineral medium and silica gel (inoculum blank + with silica gel); 10 bottles containing inoculum and mineral medium (inoculum blank without silica gel)
- Procedure control: 6 bottles containing reference substance, inoculum and mineral medium (procedure control)
- Toxicity control: No

Reference substance:

benzoic acid, sodium salt

Remarks:

2 mg/L

Preliminary study:

None.

Key result

Parameter:

% degradation (O2 consumption)

Value:

68

Sampling time:

28 d

Details on results:

Substances are considered to be readily biodegradable in the Closed Bottle test if oxygen consumption is equal to or greater than 60% of the ThOD value in the ten-day window within the 28-day period of the test (the 10-day window begins when the degree of biodegradation has reached 10% of the ThOD). However, since the test item is a multi-constituent substance, this last requirement (10-day window) is not applicable.
Test item GUM TURPENTINE OIL was biodegraded by 68% at day 28 in the Closed Bottle test.
Therefore, GUM TURPENTINE OIL is considered as readily biodegradable based on the biodegradation percentage of 68% at day 28.

Calculated ThOD of the test item: 3.29 mg O2/mg

Results with reference substance:

Calculated ThOD of the reference substance: 1.67 mg O2/mg. The biodegradation percentage of the reference substance, sodium benzoate, was 78 % at day 14.

Table 5.2.1/1: Percentage biodegradation of the test item and of the reference substance throughout the test

 

Test item and of the reference substance	Replicates	Time (days)
		0	7	14	21	28
Test Suspension (2 mg/L)	Replicate 1	0.00	61.63	76.29	70.59	67.25
	Replicate 2	0.00	65.27	65.05	62.99	68.47
	Mean	0	63	71	67	68
Procedure Control (2 mg reference substance/L)	Replicate 1	0.00	81.89	78.14	N.A.	N.A.
	Replicate 2	0.00	82.78	77.84	N.A.	N.A.
	Mean	0	82	78	N.A.	N.A.

Dissolved oxygen concentrations (mg.L^-1) throughout the test.

	Time (days)
	0	7	14	21	28
Inoculum Blank + silica gel	8.52	8.50	8.35	7.89	7.35
	8.54	8.53	8.19	7.98	7.38
Mean	8.53	8.52	8.27	7.94	7.37
Test Suspension (2 mg test item.L^-1)	8.55	4.48	3.27	3.31	2.96
	8.59	4.28	4.05	3.85	2.92
Mean	8.57	4.38	3.66	3.58	2.94
Inoculum Blank (without silica gel)	8.45	8.57	8.09	7.89	7.60
	8.38	8.53	8.16	7.90	7.62
Mean	8.42	8.55	8.13	7.90	7.61
Procedure Control(2 mg reference substance.L^-1)	8.44	5.84	5.54	N.A.	N.A.
	8.41	5.78	5.52	N.A.	N.A.
Mean	8.43	5.81	5.53	N.A.	N.A.

Validity criteria of the test:      

Inoculum blank: Oxygen depletion in the inoculum blank did not exceed 1.5 mg dissolved oxygen/L after 28 days.

Residual [O₂]: Oxygen concentrations were > 0.5 mg/L in all bottles during the test period.

Replicate values: The differences of the replicate (test suspension) values at day 28 were less than 20 %.

Reference substance: The biodegradation percentage of the reference substance, sodium benzoate, was 78% at day 14.

Thus all validity criteria of the test have been fulfilled in the present study.

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The test item, GUM TURPENTINE OIL, is considered as readily biodegradable based on the biodegradation percentage of 68% at day 28 and fulfilling the 10-day time window requirement (ca. less than 7 days).

Executive summary:

A ready biodegradability study was performed to assess the biotic degradation of test item GUM TURPENTINE OIL according to OECD Guideline 301 D and in compliance with GLP.

Ten BOD bottles were filled with mineral medium inoculated with river water and test item added at a nominal concentration of 2 mg.L^-1 with the help of silica gel. In the meantime, two series of ten blanks (with and without silica gel) were filled with inoculated mineral medium. Furthermore, six bottles containing reference substance sodium benzoate (2 mg.L^-1) were tested in order to check the procedure. The concentrations of dissolved oxygen in duplicate bottles from each group incubated at 22°C±2°C in darkness were measured at the start of the test and thereafter once a week until the end of the test (28 days for each group except the procedure control until 14 days).

The validity of the test was demonstrated by an endogenous respiration < 1.5 mgO₂.L^-1and by a biodegradation of the reference substance of 78% of its ThOD after 14 days of incubation. Moreover, the differences of the replicate values at day 28 were less than 20% and oxygen concentrations were > 0.5 mg.L^{-1 in all bottles during the test period}.

Substances are considered to be readily biodegradable in the Closed Bottle test if oxygen consumption is equal to or greater than 60% of the ThOD value in the ten-day window within the 28-day period of the test (the 10-day window begins when the degree of biodegradation has reached 10% of the ThOD).

Therefore, test item GUM TURPENTINE OIL was biodegraded by 68% at day 28. The passed level of 60% was reached after less than 7 days (approximately 6 days) upon achieving 10% of biodegradation.

Therefore, GUM TURPENTINE OIL is considered as readily biodegradable based on the biodegradation percentage of 68% at day 28 and fulfilling the 10-day time window requirement (ca. less than 7 days).

Description of key information

Test item GUM TURPENTINE OIL is considered as readily biodegradable based on the biodegradation percentage of 68% at day 28 and fulfilling the 10-day time window requirement (ca. less than 7 days).

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater

Additional information

A study was performed to assess the biotic degradation of test item GUM TURPENTINE OIL by performing a ready biodegradability test. The method followed was designed to be compliant with OECD Guideline for Testing of Chemicals No. 301 D, "Ready biodegradability – Closed Bottle Test", referenced as Method C.4-E of Commission Regulation No. 440/2008 amended by Commission Regulation (EU) 2016/266 (2) and with ISO 10634. Ten BOD bottles were filled with mineral medium inoculated with river water and test item added at a nominal concentration of 2 mg.L-¹ with the help of silica gel. In the meantime, two series of ten blanks (with and without silica gel) were filled with inoculated mineral medium. Furthermore, six bottles containing reference substance sodium benzoate (2 mg.L^-1) were tested in order to check the procedure. The concentrations of dissolved oxygen in duplicate bottles from each group incubated at 22°C ± 2°C in darkness were measured at the start of the test and thereafter once a week until the end of the test (28 days for each group except the procedure control until 14 days).

The validity of the test was demonstrated by an endogenous respiration < 1.5 mgO₂.L^-1 and by a biodegradation of the reference substance of 78% of its ThOD after 14 days of incubation. Moreover, the differences of the replicate values at day 28 were less than 20% and oxygen concentrations were > 0.5 mg.L^-1 in all bottles during the test period.

Substances are considered to be readily biodegradable in the Closed Bottle test if oxygen consumption is equal to or greater than 60% of the ThOD value in the ten-day window within the 28-day period of the test (the 10-day window begins when the degree of biodegradation has reached 10% of the ThOD). However, since the test item is a UVCB substance, this last requirement (10-day window) is not applicable.

In this study, test item GUM TURPENTINE OIL was biodegraded by 68% at day 28.

Therefore, GUM TURPENTINE OIL is considered as readily biodegradable based on the biodegradation percentage of 68% at day 28.