Reaction Mass of (4R)-4-isopropenyl-1-methylcyclohexene and (4R)-4-(2-methoxypropan-2-yl)-1-methylcyclohexene

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

01 November 2016 - 13 February 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Study was conducted in accordance with international guidelines and in accordance with GLP. All guideline validity criteria were met.

Qualifier:

according to guideline

Guideline:

OECD Guideline 121 (Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Specific details on test material used for the study:

RADIOLABELLING INFORMATION (if applicable)
- Radiochemical purity: n/a
- Specific activity: n/a
- Locations of the label: n/a
- Expiration date of radiochemical substance: n/a

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: 6 ºC ± 2 ºC, protected from light and under nitrogen.
- Stability under test conditions: Stable
- Solubility and stability of the test substance in the solvent/vehicle: Soluble and stable
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: No

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: Dissolved in acetonitrile to form a 100 mg/L stock solution.
- Preliminary purification step (if any): n/a
- Final dilution of a dissolved solid, stock liquid or gel: n/a
- Final preparation of a solid: n.a

FORM AS APPLIED IN THE TEST (if different from that of starting material) n/a

OTHER SPECIFICS: n/a

Radiolabelling:

no

Test temperature:

20 - 25 ± 1ºC

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: Autosampler, binary solvent manager, column manager, DAD-detector
- Type: Acquity UPLC
- Type, material and dimension of analytical (guard) column: YMC-Pack-Cyano, S-5 µm, 12 nm, 250 x 4.0 mm, batch 13303, YMC Europe GMBH.
- Detection system: Photodiode array detector (DAD)

MOBILE PHASES
- Type: Acetonitrile: HPLC water (60:40 v/v)
- Experiments with additives carried out on separate columns: no
- pH: 5.5 - 7.5 (test item not ionisable)
- Solutes for dissolving test and reference substances: Acetonitrile and HPLC water.

DETERMINATION OF DEAD TIME
- Method: by means of homologous series / by inert substances which are not retained by the column (threefold injection of a solution of 5 mg/L sodium nitrate).

REFERENCE SUBSTANCES
- Identity: Atrazine, 4-nitrobenzamide, monuron, aniline, linuron, fenthion, phenanthrene, 4,4-DDT.

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: 10 mg/L (10 µL injection)
- Quantity of reference substances: 5 mg/L (10 µL injection)
- Intervals of calibration: Before and after test item.

REPETITIONS
- Number of determinations: Test item = 3. Reference item = Single injections before and after test item.

EVALUATION
- Calculation of capacity factors k': (retention time - dead time) / dead time
- Calculation of adsorption coefficients: linear regression of the log k' of the reference items against the log koc of the reference items
- Determination of the log Koc value: log koc = slope of the calibration curve x log k + y-intercept of the calibration curve.

Key result

Type:

Koc

Value:

>= 2.86 - <= 3.89

Matrix:

Soil

Remarks on result:

other: determined by HPLC method

Key result

Type:

Koc

Value:

>= 2.78 - <= 4.03

Matrix:

Sewage sludge

Remarks on result:

other: determined by HPLC method

Details on results (HPLC method):

- Retention times of reference substances used for calibration:
-atrazine = 4.413 - 4.411 mins
-4-nitrobenzamide = 3.753 - 3.750 mins (values discounted as outliers and not used in calculations)
- monuron = 4.236 - 4.231 mins
- aniline = 4.686 - 4.717 mins
- linuron = 5.261 - 5.258 mins
- fenthion = 6.605 - 6.599 mins
- phenanthrene = 6.784 - 6.791 mins
- 4,4-DDT = 10.288 - 10.317 mins

- Details of fitted regression line (log k' vs. log Koc):
-atrazine: log k' = -0.111 to -0.112 and log koc(soil) = 1.81 and log koc(sludge) = 1.66
-monuron: log k' = -0.153 to -0.154 and log koc(soil) = 1.99 and log koc(sludge) = 1.46
-aniline: log k' = -0.0536 to -0.0475 and log koc(soil) = 2.07 and log koc(sludge) = 1.74
-linuron: log k' = 0.0473 to 0.0469 and log koc(soil) = 2.59 and log koc(sludge) = 2.43
-fenthion: log k' = 0.219 to 0.218 and log koc(soil) = 3.31 and log koc(sludge) = 3.75
-phenanthrene: log k' = 0.237 to 0.238 and log koc(soil) = 4.09 and log koc(sludge) = 4.35
-4,4-DDT: log k' = 0.496 to 0.498 and log koc(soil) = 5.63 and log koc(sludge) = not determined

4 - Graph of regression line attached: yes
- Average retention data for test substance:
-peak 1 = 5.344 - 3.353 mins
-peak 2 = 6.773 - 6.792 mins

Table 1       Capacity factors (k') of the reference items for soil and sewage sludge

Reference Item	logKOC,soil	logKOC,sewage sludge	1^stCalibration			2^ndCalibration
			tR1 [min]	k'	logk'	tR2 [min]	k'	logk'
Atrazine	1.81	1.66	4.413	0.774	-0.111	4.411	0.773	-0.112
4-Nitrobenzamide^1	1.93	1.52	3.753	0.509	-0.203	3.750	0.508	-0.294
Monuron	1.99	1.46	4.236	0.703	-0.153	4.231	0.701	-0.154
Aniline	2.07	1.74	4.686	0.884	-0.0536	4.717	0.896	-0.0475
Linuron	2.59	2.43	5.261	1.12	0.0473	5.258	1.11	0.0469
Fenthion	3.31	3.75	6.605	1.66	0.219	6.599	1.65	0.218
Phenanthrene	4.09	4.35	6.784	1.73	0.237	6.791	1.73	0.238
4.4-DDT	5.63	-	10.288	3.14	0.496	10.317	3.15	0.498

t_R1 = Retention time 1. Injection

t_R2 = Retention time 2. Injection
k’ = Capacity factor

K_OC = Adsorption coefficient

1 = Outlier, not included in calculations

Table 2       Retention time, capcity factors and adsorption coefficients of Reaction mass of (4R)-4-isopropenyl-1-methylcyclohexene and (4R)-4-(2 -methoxypropan-2-yl)-1-methylcyclohexene (Peak 1)

Reaction mass of (4R)-4-isopropenyl-1-methylcyclohexene and (4R)-4-(2-methoxypropan-2-yl)-1-methylcyclohexene– Peak 1
Rep	tR [min]	k’	logk’	logKOC.soil 95 % CI		logKOC.sewagesludge 95 % CI
				1^stCalibration	2^ndCalibration	1^stCalibration	2^ndCalibration
1	5.344	1.15	0.0601	2.86 ± 0.12 2.54 to 3.17	2.85 ± 0.12 2.53 to 3.17	2.78 ± 0.11 2.47 to 3.09	2.77 ± 0.12 2.45 to 3.09
2	5.345	115	0.0603
3	5.353	1.15	0.0615
Mean	5.35	1.15	0.0606	2.86		2.78

tR = retention time

CL = confidence intervals

Table 3       Retention time, capcity factors and adsorption coefficients of Reaction mass of (4R)-4-isopropenyl-1-methylcyclohexene and (4R)-4-(2 -methoxypropan-2-yl)-1-methylcyclohexene (Peak 2)

Reaction mass of (4R)-4-isopropenyl-1-methylcyclohexene and (4R)-4-(2-methoxypropan-2-yl)-1-methylcyclohexene– Peak 2
Rep	tR [min]	k’	logk’	logKOC.soil 95 % CI		logKOC.sewagesludge 95 % CI
				1^stCalibration	2^ndCalibration	1^stCalibration	2^ndCalibration
1	6.773	1.72	0.236	3.89 ± 0.14 3.52 to 4.26	3.88 ± 0.14 3.51 to 4.25	4.03 ± 0.19 3.52 to 4.54	4.03 ± 0.19 3.50 to 4.55
2	6.779	1.73	0.237
3	6.792	1.73	0.238
Mean	6.78	1.73	0.237	3.89		4.03

Validity criteria fulfilled:

yes

Conclusions:

The log Koc for the test item in soil and sewage sludge is 2.86 - 3.89 and 2.78 - 4.03 at 23.7 ºC, respectively.

Executive summary:

OECD 121 (2017) - The adsorption coefficient (K_OC) for the test item, Reaction mass of (4R)-4-isopropenyl-1-methylcyclohexene and (4R)-4-(2-methoxypropan-2-yl)-1-methylcyclohexene, on soil and on sewage sludge using high performance liquid chromatography (HPLC) was estimated according to OECD 121 (2001) and Council Regulation (EC) No. 440/2008, Method C.19.

The test was performed at one pH value since the test item is not ionisable in the relevant pH range 5.5 to 7.5 and temperature controlled (23.71 °C, mean value). Acetonitrile:HPLC water(60:40 v/v)was used as mobile phase. A 10mg/L sample of the test item was analyzed threefoldviaHPLC on a cyanopropyl (CN-) column with DAD detection.

Calibrations were performed using eightreference items for soil and seven for sewage sludgewith known logK_OCvalues (given by the guidelines). The reference items were measured twice, once before and once after the measurement (double injection of one replicate) of the test item. Dead time of the HPLC-system was determined with sodium nitrate. Two individual logK_OCvaluesfor soil andforsewage sludge forthe test item were derived under consideration of the first and second calibration at each pH value. Since two peaks with comparable UV spectra were determined, logK_OCvalues were calculated for both peaks.

The log Koc for the test item in soil and sewage sludge was determined to be 2.86 - 3.89 and 2.78 - 4.03, respectively, at 23.7 ºC.

Description of key information

Log Koc soil = 3.98, Log Koc sludge = 4.03; OECD 121; Anon. (2017)

Key value for chemical safety assessment

Koc at 20 °C:

7 762

Additional information

In a study conducted in accordance with OECD 121, the adsorption coefficient (K_OC) for the test item, on soil and on sewage sludge using high performance liquid chromatography (HPLC) was estimated according to OECD 121 (2001) and Council Regulation (EC) No. 440/2008, Method C.19.

The test was performed at one pH value since the test item is not ionisable in the relevant pH range 5.5 to 7.5 and temperature controlled (23.71 °C, mean value). Acetonitrile:HPLC water (60:40 v/v) was used as mobile phase. A 10mg/L sample of the test item was analyzed threefold via HPLC on a cyanopropyl (CN-) column with DAD detection.

Calibrations were performed using eightreference items for soil and seven for sewage sludgewith known log K_OC values (given by the guidelines). The reference items were measured twice, once before and once after the measurement (double injection of one replicate) of the test item. Dead time of the HPLC-system was determined with sodium nitrate. Two individual log K_OC values for soil and forsewage sludge for the test item were derived under consideration of the first and second calibration at each pH value. Since two peaks with comparable UV spectra were determined, log K_OC values were calculated for both peaks.

The log Koc for the test item in soil and sewage sludge was determined to be 2.86 - 3.89 and 2.78 - 4.03, respectively, at 23.7 ºC.

Based on the knowledge of constituent specific water solubility and partition coefficients (KREATIS, 2017), the following Koc values were assigned to each constituent:

Constituent 1:

Log Koc soil = 3.89

Log Koc sludge = 4.03

Constituent 2:

Log Koc soil = 2.86

Log Koc sludge = 2.78

[LogKoc: 3.89]