(3-chloro-2-hydroxypropyl)trimethylammonium chloride

Biodegradation in water and sediment: simulation tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: sediment simulation testing

Data waiving:

exposure considerations

Justification for data waiving:

the study does not need to be conducted because direct and indirect exposure of sediment is unlikely

Reference 2

Endpoint:

biodegradation in water: simulation testing on ultimate degradation in surface water

Data waiving:

exposure considerations

Justification for data waiving:

the study does not need to be conducted because direct and indirect exposure of sediment is unlikely

Reference 3

Endpoint:

biodegradation in water: sewage treatment simulation testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2005-06-15 to 2006-10-28

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 303 A (Simulation Test - Aerobic Sewage Treatment. A: Activated Sludge Units)

Deviations:

yes

Remarks:

pH of the stock solution was adjusted to pH4 to provide adequate stability during application

GLP compliance:

yes (incl. QA statement)

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Details on source and properties of surface water:

- Details on collection (e.g. location, sampling depth, contamination history, procedure): Domestic sewage was collected from the overflow channel of the primary sedimentation tank or the feed of the activated sludge plant of the municipal sewage treatment plant at D-31137 Hildesheim. Synthetic sewage was prepared according to the test guideline and used for DOC adjustment of the domestic sewage if necessary.

- Storage conditions: Stored at 4°C

- Storage length: Maximum 7 days

Details on source and properties of sediment:

Not applicable

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Activated sludge from the municipal sewage treatment plant at D-31137 Hildesheim.

- Storage conditions: Aeration at room temperature

- Concentration of sludge: Starting concentration of dry matter 1.25 to 2.40 g/l

Duration of test (contact time):

96 d

Initial conc.:

30.6 mg/L

Based on:

DOC

Initial conc.:

78.4 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

DOC removal

test mat. analysis

Details on study design:

Simulation test - aerobic sewage treatment according to US EPA, OPPTS 835.3220 April 1996, Porous Pot Test and OECD 302 A.

The degradation was studied in a continously operating porous pot with activated sludge from a municipal sewage treatment plant over a test period of 135 days. The influent was adjusted to 200 mg DOC/l. After 40 days of flow, when the DOC elimination was constant >80 %, the test item was added.

The stock solution was adjusted to pH 4 +- 0.5 in order to stabilise the test item. With regard to the low volumes applied the pH value of the porous pot reactor was not markedly influenced. Influent concentration of the test item was 30.6 mg/L DOC which is higher than normal mean test concentration 10-20 mg/l DOC according to OECD quideline (with upper concentration of no more than 50 mg/l).

Activated sludge: pH values were partly outside the specified range 7 to 8. These slight deviations were temporary and found to be negligible. Therefore, no adjustments were made.

Analysis comprised of DOC analysis and specific test item analysis including two known hydrolysis or conversion products EPTAC and DHPTAC (Di-hydroxypropyl trimethylammonium chloride).

Guideline OECD 303 A does not require substance specific analysis, although it has been performed in this study.

Reference substance:

not required

Key result

% Degr.:

ca. 28

St. dev.:

14.3

Parameter:

test mat. analysis

Remarks on result:

other: Sampling time 61-74 days after test item application

Transformation products:

not measured

Evaporation of parent compound:

no

Volatile metabolites:

no

Residues:

no

Details on results:

All elimination/primary degradation values are based on measured concentrations of all three compounds CHPTAC, EPTAC and DHPTAC.
The elimination of the parent substance, CHPTAC, was in the range of 5–45%. No clear degradation tendency was observed and no plateau phase was reached (see Table 5). The mean elimination/primary degradation was calculated on 14 consecutive values from study days 100–113, corresponding to days 61–74 of test item application. The mean elimination/primary degradation was 28 ± 14.3 %, expressed as active ingredient.
All elimination/primary degradation values are based on measured concentrations of all three compounds CHPTAC, EPTAC and DHPTAC.
DOC elimination during the phase of test substance addition was between 72 and 92 %.

Results with reference substance:

Not applicable

Table 5: Elimination of CHPTAC based on measured concentrations of CHPTAC, EPTAC and DHPTAC

Phase	Study day	Day of test item application	Effluent (mmol/l)	Elimination/Primary degradation (%)
	48	9	0.39	5
	54	15	0.17	59
	57	18	0.39	7
	61	22	0.31	25
	64	25	0.33	20
	76	37	0.30	28
	82	43	0.36	13
	92	53	0.31	27
	99	60	0.19	55
Calculation of mean elimination	100	61	0.25	39
	101	62	0.23	45
	102	63	0.39	7
	103	64	0.37	12
	104	65	0.39	5
	105	66	0.31	25
	106	67	0.31	25
	107	68	0.36	13
	108	69	0.28	32
	109	70	0.26	38
	110	71	0.25	40
	111	72	0.31	25
	112	73	0.21	49
	113	74	0.26	37

 

Validity criteria fulfilled:

yes

Conclusions:

In an OECD 303A porous pot test, elimination of CHPTAC was in the range 5-45%. No clear degradation tendency was observed and no plateau phase was reached. The mean elimination/primary degradation was 28 ± 14.3 % based on measured concentrations of the three substances CHPTAC, EPTAC and DHPTAC in effluent on days 61–74 of test item application.

Description of key information

In an OECD 303A porous pot test, elimination of CHPTAC was in the range 5-45%. No clear degradation tendency was observed and no plateau phase was reached. The mean elimination/primary degradation was 28 ± 14.3 % based on measured concentrations of the three substances CHPTAC, EPTAC and DHPTAC in effluent on days 61–74 of test item application.

In accordance with Column 2 of REACH Annex X, simulation studies on the ultimate degradation in surface water and sediment is not needed as the chemical safety assessment according to Annex I indicates that exposure of the substance to surface water and sediment is not expected.