Aluminium trilactate

Long-term toxicity to fish

Description of key information

No data on long term toxicity to fish are available for the substance Aluminium trilactate. Thus, a read-across to the moieties of Aluminium trilactate - Lactic acid and Aluminium is used for hazard assessment. This read-across approach is adequate as the salt Aluminium trilactate will dissociate into Lactic acid and Aluminium ions in aqueous solutions.  
One long term study with Lactic acid as well as two studies with Aluminium are available.
In a 90-day chronic toxicity study the minimum effective concentration of Lactic acid that caused a significant reduction in food conversion factor, specific growth rate, percent increase in weight, yield, and fecundity over control in juvenile tilapia (Oreochromis mossambicus) was determined to be 2.18 mg/L (nominal). 
A 28/42-day study assessed the chronic toxicity of Aluminium to early life stage (artificially implanted eggs, alevins and parr) of brown trout Salmo trutta (L.) in natural streams of different acidity. The 28 d-LC50 was 19 µg/L, the 42 d-LC50 was 15 µg/L. 
In a 60-day chronic toxicity study of Aluminium sulfate hexadecahydrate to Salvelinus fontinalis, the lowest NOEC was determined for incomplete hatching to be 13 µg/L dissolved Al. 
Some publications suggest lower NOECs being in the range of naturally occurring Aluminium concentrations (from 0.001 to 0.05 mg/L, and up to 0.5 - 1 mg/L in more acidic waters or water rich in organic matter, according to WHO, 1998). 
LAWA (2010) concluded that even though the studies are inherently valid, such data are not relevant for natural waters. The authors assume that the effective concentrations may be artefacts due to relating to incorrect Aluminium species.
LAWA (2010) and Environment Canada (2010) suggest a limit concentration (critical toxicity value, CTV) of 50 µg Al/L and 60 µg Al/L, respectively. Following this approach a NOEC of 50 µg Al/L corresponding to 0.55 mg/L Aluminium trilactate will be used. 

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

0.55 mg/L

Additional information

No data on long term toxicity to fish are available for the substance Aluminium trilactate. Thus, a read-across to the moieties of Aluminium trilactate - Lactic acid and Aluminium is used for hazard assessment. This read-across approach is adequate as the salt Aluminium trilactate will dissociate into Lactic acid and Aluminium ions in aqueous solutions. 

One long term study with Lactic acid as well as two studies with Aluminium are available:

The chronic toxicity of Lactic acid to juvenile tilapia (Oreochromis mossambicus) was investigated in a study conducted according to the recommendations of APHA (1995). The 90 d chronic toxicity tests were conducted in outdoor earthern vats. Behaviour and survival were examined twice daily. After a 90 d exposure period, no mortality of fish occurred and there was no apparent change in behaviour and colour of the exposed fish. The condition factor did not show any variation between the treatments. The maturity index of male fish significantly reduced in all concentrations tested whereas that of female fish decreased only in concentrations ranging from 5.08 to 25.41 mg/L. The minimum effective concentration of lactic acid that caused a significant reduction in food conversion factor, specific growth rate, percent increase in weight, yield, and fecundity over control was determined to be 2.18 mg/L (nominal).

The study is regarded as reliable with restrictions although some information e.g. on test conditions are missing as the study was conducted according to the recommendations of APHA.

The 28/42-day chronic toxicity of Aluminium to early life stage (artificially implanted eggs, alevins and parr) of brown trout Salmo trutta (L.) was studied in natural streams of different acidity. 300 fertilized eggs ofSalmo truttawere exposed to measured concentrations of 3, 5.2, 5.6, 12, 34, 56, 88, 377, 397 µg Al/L. 

Chemical analysis included detailed aluminium speciation of surface and interstitial water samples, taken over the duration of intragravel life stages. Egg survival, from two minutes after fertilization to hatching, was usually above 71%, and was independent of the mean concentration of total monomeric aluminium over the range 3 - 397 µg/L.

The survival of alevins exposed for 28 days (before 'swim-up') or 42 days ('swim-up') was most strongly related to mean total monomeric aluminium concentration and to pH. For 28- and 42-day exposures, LC50 values for Al were approximately 19 and 15 µg/L, respectively.

The 21-dayLC50 of parr (ca 3 months old) was > 84 µg Al/L.

The 60-day chronic toxicity of Aluminium sulfate hexadecahydrate to Salvelinus fontinalis (brook trout) was studied under static renewal conditions similar to OECD guideline 210. In the first exposure (exposure A), eyed eggs of brook trout and the resultant larvae and juveniles were exposed to nominal Al concentrations of 38, 75, 150, and 300 µg/L at pH5.5; controls (no Al added) were held at pH 5.5 and 7.2. In the second exposure (exposure B), eyed eggs and the resultant larvae and juveniles were exposed to nominal Al concentrations of 50, 100,200, and 400 µg/L at pH 6.5; controls were held at pH 6.5 and 7.2. Because Al is less soluble under less acidic conditions and its toxicity to fish decreases, slightly higher Al exposure concentrations were used in exposure B than in A. The exposures were conducted in soft water containing about 3.0 mg/L Ca. The sublethal effects included were mortality in fry, weight, swimming capacity, and hatching. The most sensitive endpoint was hatching.The lowest NOEC was determined for incomplete hatching to be 13 µg/L dissolved Al.

Long term toxicity of Aluminium to fish has also been reviewed by Environment Canada (2010), LAWA (2010), WHO IPCS EHC (1997) and US ATSDR (2008). These reviews and the literature cited therein have also been taken into account for hazard assessment.

Some publications suggest lower NOECs being in the range of naturally occurring Aluminium concentrations (from 0.001 to 0.05 mg/L, and up to 0.5 - 1 mg/L in more acidic waters or water rich in organic matter, according to WHO, 1998).

LAWA (2010) concluded that even though the studies are inherently valid, such data are not relevant for natural waters. The authors assume that the effective concentrations may be artefacts due to relating to incorrect Aluminium species.

LAWA (2010) and Environment Canada (2010) suggest a limit concentration (critical toxicity value, CTV) of 50 µg Al/L and 60 µg Al/L, respectively. Following this approach a NOEC of 50 µg Al/L corresponding to 0.55 mg/L Aluminium trilactate will be used.

References:

Environment Canada (2010)Environment Canada Priority Substance List Assessment Report, Follow-up to the State of Science Report, 2000 Aluminium Salts (Final Content), available via internet: http://www.ec.gc.ca/lcpe-cepa/default.asp?lang=En&n=491F0099-1 and http://www.ec.gc.ca/lcpe-cepa/documents/substances/sa-as/final/al_salts-eng.pdf

 

LAWA (Bund/Länder-Arbeitsgemeinschaft Wasser) (2010)Stoffdatenblatt Aluminium-Kation (14903-36-7), Available via internet: http://www.laenderfinanzierungsprogramm.de/cms/WaBoAb_prod/WaBoAb/Vorhaben/LAWA/Vorhaben_des_Ausschusses_Oberflaechengewaesser_und_Kuestengewaesser_%28AO%29/O_5.07/L4_db_Aluminium_Datenblatt_UQN-Vorschlag_100315.pdf

 

US ATSDR (United States Agency for Toxic Substances and Disease Registry)(2008) Toxicological profile for Aluminium, U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES, Public Health Service, Agency for Toxic Substances and Disease Registry, available via internet: http://www.atsdr.cdc.gov/toxprofiles/tp.asp?id=191&tid=34

 

WHO (World Health Organisation) 1998, Aluminium in Drinking-water,Background document for development of WHOGuidelines for Drinking-water Quality,2nd ed. Addendum to Vol. 2.Health criteria and other supporting information.

 

WHO IPCS EHC (World Health Organisation International Programme on Chemical Safety Environmental Health Criteria)(1997) Aluminium (Environmental health criteria; 194), IPCS, World Health Organization, Geneva, available via internet: http://www.inchem.org/documents/ehc/ehc/ehc194.htm