Amines, C14-16 (even numbered)-alkyldimethyl, N-oxides

Endpoint summary

Additional information

Fish: No acute fish toxicity studies have been performed using C14 -16 AO. Data are available for category members C12 AO, C14 AO, C12 -14 AO and C12 -18 AO. These data demonstrate an increase in acute toxicity to fish as chain length increases moving from C12 AO to C14 AO and C12-14 AO. The acute toxicity to fish of C12-18 AO is of the same order of magnitude as C12-14 AO. The LC50 (96 h) for fish is 1.26 mg AO/L, based on the lowest LC50 derived from the key study performed using C12-18 AO [Rowlands (2005)].

In a full life-cycle toxicity test (similar to EPA OPPTS 850.1500) fathead minnows (Pimephales promelas) were exposed to C12 -14 AO for 302 days under flow through conditions [Aquatic Environmental Services (1976) ]. The NOEC was 0.42 mg AO/L (mean measured concentration), based on reduced fry survival, reduced egg hatch, and occluded eyes in test fish.

Daphnia: No acute daphnia toxicity studies have been performed using C14-16 AO. Data are available for category members C12 AO, C14 AO, C12-14 AO and C12-18 AO. These data demonstrate a small increase in acute toxicity to daphnia magna as chain length increases moving from C12 AO to C12-14 AO, C14 AO and C12-18 AO. The EC50 (48 h) for Daphnia magna is 2.4 mg AO/L, based on the lowest EC50 derived from the key study performed using C12-18 AO [Noack (2001)].

A 21-day survival and reproduction test with Daphnia magna following OECD TG 211 is available for C12-14 AO [Maki (1997) ]. The 21 -day NOEC was 0.70 mg AO/L, based on both survival and reproduction.

Algae: No acute algal toxicity studies have been performed using C14 -16 AO. Data are available for category members C10 AO, C12 AO, C14 AO, C12-14 AO and C12-18 AO. The 72-h ErC50 for algae of 0.163 mg AO/L is calculated as the geometric mean of the results from the studies performed on Pseudokirchnerella subcapitata which appears to be the most sensitive algal species based on the available data.

The toxicity of C12-14 AO to algae was evaluated in a 28 -day freshwater periphyton microcosm assay [Belanger (1999)]. The No-Observed Effect Concentration (NOEC) of the substance to the periphyton community was determined to be>67 µg AO/L, the highest test concentration evaluated (mean measured concentration). This study is read across to C14 -16 AO based on the insensitivity to alkyl chain length demonstrated in the acute studies.

Microorganisms: No studies investigating the toxicity to micro-organisms have been performed using C14-16 AO. Data are available for category members C12 -14 AO and C12 -18 AO. These substances exhibit similar toxicity to Pseudomonas putida when exposed for 18 hours in a Bringmann-Kohn test. The value of 24 mg AO/L from the study with C12-14 AO is used for the chemical safety assessment for C14-16 AO [Kolvenbach (1990)].

Sediment-dwelling organisms: No studies are available, however risk characterisation using the equilibrium partitioning method indicates that the risk to sediment dwelling organisms is adequately controlled and there is no need for further refinement of the assessment through testing.

Terrestrial toxicity: No studies are available, however risk characterisation using the equilibrium partitioning method indicates that the risk to terrestrial organisms is adequately controlled and there is no need for further refinement of the assessment through testing.