Bis(2-hydroxyethyl)ammonium acetate

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

0.1 mg/L

Assessment factor:

1 000

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

1 mg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0.01 mg/L

Assessment factor:

10 000

Extrapolation method:

assessment factor

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

100 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

0.085 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

0.009 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Hazard for air

Air

Hazard assessment conclusion:

no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:

PNEC soil

PNEC value:

0.017 mg/kg soil dw

Extrapolation method:

equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

PNEC oral

PNEC value:

6.67 mg/kg food

Assessment factor:

300

Additional information

No studies were available on DEA acetate specifically. However, reliable data on closely-related substances was used for characterisation of hazards to the environment and as a basis for PNEC determination.

Aquatic toxicity

As only short-term toxicity data on freshwater species were available on structurally closely-related substances from three trophic levels, LC50/EC50 values were used as a basis for deriving freshwater and marine water PNECs. For such cases, the REACH guidance (ECHA, 2008; R.10 of the IR&CSA) recommends using assessment factors of 1000 and 10,000 for freshwater and marine water, respectively. The EC50/LC50 was above 100 mg/l, so application of AFs of 1000 and 10,000 is considered conservative.

 

A PNEC aqua for intermittent releases were also determined using the appropriate AF of 100 given in ECHA (2008) guidance (R.10 of the IR&CSA).

Microorganisms in sewage treatment plants (STPs)

Activated sludge tests on reliable surrogates found no significant effect on respiration rate at the highest tested concentration of 1000 mg/L (the NOEC). In each case, the 3-hr EC50 was greater than 1000 mg/L. An AF of 10 is appropriate when applying to NOEC from a guideline study.

 

Sediments and soils

Sediment (in fresh and marine water) and soil PNECs were derived in EUSES version 2.1 software using the partition coefficient method.

 

Atmospheric compartment

No data are available on possible effects of DEA acetate on the atmosphere. However, given its low volatility, neither biotic nor abiotic effects (e.g. global warming, ozone depleting, acidification) are likely.

Secondary poisoning

The oral (secondary poisoning) PNEC calculation was based on a NOAEL of 200 mg/kg bw/day from the 28-day rat studies on RA1 and RA2 (Allard and Becker, 1997; Braun et al. 2000), corresponding to a NOEC of 2000 mg/kg food (using a conversion factor of 10). The recommended assessment factor of 300 was applied. 

 

Based on the above and together with classification considerations, it is evident that DEA acetate is a substance of low environmental concern.

Conclusion on classification

According to Regulation (EC) No. 1272/2008, a substance poses an acute aquatic hazard if the 96-hr LC50 for fish, the 72- or 96-hr EC50 for algae, or the 48-hr EC50 for crustaceans is 1 mg/L or less. Read-across compounds (TEA acetate, RA1 and RA2) have been subject to 96-hr acute toxicity tests on carp, zebrafish and rainbow trout, all giving LC50 values above 100 mg/L (Bouwman, 2010a; Grutzner, 1997a; Peither, 2000a). EC50s in algae for TEA acetate and RA2 were both above 100 mg/L (Bouwman, 2010b; Grutzner, 1997c). For daphnia, EC50s of over 100 mg/L have been reported for RA1 and RA2 (Grutzner, 1997b; Peither, 1999). No reduction in respiration rate was seen to microorganisms in 3-hr activated sludge tests on RA1 and RA2 at up to the NOEC of 1000 mg/L (Grutzner, 1997d; Peither, 2000b). These results lend strong support to the idea that DEA acetate is likely to be of low aquatic toxicity.

Also, according to Regulation (EC) No. 1272/2008, a cut-off value of Log Kow ≥ 4 can be used to identify substances with a real potential to bioconcentrate. The partition coefficient of DEA acetate (Log Pow) is expected to be less than -1.31, indicating a low potential for bioaccumulation (Brekelmans, 2010a, b). The Regulation also states that a bioconcentration factor (BCF) in fish of at least 500 indicates a potential to bioconcentrate. The BCF for the read-across compound TEA acetate has been determined as 1.41 using EUSES version 2.1. DEA acetate is not considered as bioaccumulative.

Regarding persistence, TEA acetate has been tested for ready biodegradability. Although the strict criterion for ready biodegradability was not met (according to Regulation (EC) No. 1272/2008, for tests based on CO₂ generation: 60 % biodegradation within 10 day window), it biodegraded significantly during the 28-day test period (50 and 63 %) and thus it is considered inherently biodegradable (Desmares-Koopmans, 2010). 

In conclusion, DEA acetate is not classified as harmful to the aquatic environment as it is not expected to be persistent, bioaccumulative or toxic.