Quaternary ammonium compounds, bis(C16-18 and C18-unsatd. alkyl)dimethyl, chlorides

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

For details on endpoint specific justification please see read-across report in section 13 or find a link in cross-reference “assessment report”.

Reason / purpose for cross-reference:

assessment report

Reason / purpose for cross-reference:

read-across source

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.38 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

other: reproduction and mean length

Remarks on result:

other: Water from White river: pH 8.4-8.6, 345-363 mg/L CaCO3, 3-5 mg/L susp. matter

Duration:

21 d

Dose descriptor:

LC50

Effect conc.:

1.72 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

reproduction

Remarks on result:

other: Water from White river: pH 8.4-8.6, 345-363 mg/L CaCO3, 3-5 mg/L susp. matter

Validity criteria fulfilled:

yes

Conclusions:

The source substance DODMAC (14C-labelled) was tested for long-term toxicity towards aquatic invertebrates (Daphnia magna) in a 21 d Daphnia reproduction study performed similar / equivalent to OECD 211. The semi-static test (daily renewal) was performed in river water with 3-5 mg/L susp. matter. The following results relevant for the target substance DTDMAC were determined:
NOEC (Daphnia magna; 21 day; semi-static; mean measured; length, total young, mean brood size): 0.38 mg/L;
LOEC (Daphnia magna; 21 day; semi-static; mean measured; length, total young, mean brood size): 0.76 mg/L.
LC50 (Daphnia magna; 21 day; semi-static; mean measured): 1.72 (95% CI = 1.31-2.49) mg/L.
The MW difference between source and target substance is low (formally, a factor of 0.904 were needed to adapt effect concentrations to the target substance). Considering the overall variability observed as a function of the suspended solids content of test waters, the effect of the molecular weight difference between source and target on effect concentrations is negligible and thus no correction was performed.

Executive summary:

The study used as source investigated the long-term toxicity towards aquatic invertebrates using the source substance DODMAC in a study performed similar / equivalent to OECD 211. The study results determined for the source substance were considered applicable to the target substance. Justification and applicability of the read-across approach (structural analogue) is outlined in the read-across report in section 13 or find a link in cross reference “assessment report”.

Description of key information

Toxicity figure based on river water testing with DODMAC (read-across).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.38 mg/L

Additional information

Read across for DTDMAC from structurally similar Quats DHTDMAC/DODMAC can be applied and the corresponding effect data form DHTDMAC/DODMAC used for DTDMAC as well.

Key study for long-term toxicity towards aquatic invertebrates:

The source substance DODMAC (14C-labelled) was tested for long-term toxicity towards aquatic invertebrates (Daphnia magna) in a 21 d Daphnia reproduction study performed similar / equivalent to OECD 211. The semi-static test (daily renewal) was performed in river water with 3-5 mg/L susp. matter. Most relevant parameters for this study type are reported in the scientifically valid publication (Lewis and Wee, 1983), including details on the test item used. Further, the study was assessed as relevant within the EU-RAR for DODMAC (ECB, 2009). Accordingly, it was assigned a Klimisch reliability score of 2 (Klimisch et al., 1997).

The following results relevant for the target substance DTDMAC were determined:

NOEC (Daphnia magna; 21 day; semi-static; mean measured; length, total young, mean brood size): 0.38 mg/L;

LOEC (Daphnia magna; 21 day; semi-static; mean measured; length, total young, mean brood size): 0.76 mg/L.

LC50 (Daphnia magna; 21 day; semi-static; mean measured): 1.72 (95% CI = 1.31-2.49) mg/L.

The MW difference between source and target substance is low (formally, a factor of 0.904 were needed to adapt effect concentrations to the target substance). Considering the overall variability observed as a function of the suspended solids content of test waters, the effect of the molecular weight difference between source and target on effect concentrations is negligible and thus no correction was performed.

Further available data:

In the Endpoint Summary Aquatic toxicity (IUCLID Chapter 6.1) an Overview table with the available chronic invertebrate tests is given. From the EU Risk Assessment DODMAC (EU, 2002) the following discussion on chronic invertebrate toxicity is available:

Chronic toxicity to Invertebrates

In a semistatic 21d-study (OECD 202) with Daphnia magna DHTDMAC (76.6% active ingre­dient) was emulsified in reconstituted groundwater by treatment for 30 minutes in an ultrasonic vibration bath (Akzo, 1991a). All test vessels were conditioned with the test solutions 24 hours before the start of the test. The most sensitive endpoint was the reproduction rate with a NOEC of 0.18 mg/l (nominal concentration of active ingredient). The NOEC for adult morta­lity was 0.56 mg/l. Test substance was analyzed at the end of the test only for concentrations of 0.56 mg/l and higher showing that they had not decreased in the course of the test. Analytical determination of all test concentrations at the start of the test revealed higher measured concentrations than nominal concentrations in tests up to 0.10 mg/l.

The toxicity of DODMAC to Ceriodaphnia dubia was investigated in a 7 day static renewal test (Versteeg & Shorter, 1993). As test medium filtered water from the Little Miami River, Ohio, was used (5.4 mg/l total organic carbon, pH = 8.1 - 8.4, hardness = 171 mg/l CaCO3). Based on reproduction the EC20 was 0.26 mg/l and the EC50 was 0.70 mg/l (measured con­centrations). Survival was affected from 0.41 mg/l upwards. These results have to be treated with care as the reproduction was decreased by exposure to the carrier solvent acidic methanol alone. Results fromTaylor, 1984 (cited in ECETOC, 1993) were similar for DHTDMAC tested inOhio Riverwater. A 7 d EC50 of 0.78 mg/l and an EC20 for reproduction of 0.20 mg/l were reported (nominal conc.). DODMAC was synthesized by a special route which ensures no MTTMAC.

In tests reported by Versteeg (1987) DTDMAC (this is assumed to be DHTDMAC) concentrations were produced by treatment of surfactant containing influents of two municipal wwtps in a laboratory scale continuous activated sludge system (CAS). The influent was supple­mented with different amounts of 0, 1 and 3% untreated industrial plant wastewater. This resulted in different DTDMAC concentrations in the effluent matrix which were diluted with Little Miami River water. (The system was preacclimatized for 32 days.) Toxicity to Ceriodaphnia dubia was measured in a 7 d reproduction test with the effluents diluted with river water. MATC-values were lowest in theCASeffluents where no industrial waste water was added additionally with 99 and 267 µg/l DTDMAC, which is similar to studies with river water. In the CAS effluents where industrial wastewater was added toxicity was reduced to between 1.0 and 3.75 mg/l, demonstrating the high influence of the effluent matrix. The concentrations of total suspended solids in the first case were 3.8 and 6.6 mg/l and in the second case 13 to 33 mg/l which might be one possibility of explanation for the different toxicities. The concentration of MTTMAC increased with decreasing toxicity.