4.2.2.1-Toxicity 
A limit test according to OECD 203 did not show any adverse effects to fish at a test concentration of 1 g/L L-arginine. 
A subsequent test with L-arginine according to OECD 203 with higher test concentrations showed the following results: 
LC50 = 2.8 g/L; LC 100 = 5.6 g/L; NOEC (mortality) = 1.8 g/L; NOEC (condition) = 1.0 g/L.
EC50 was found to be 1.8g/L,EC100 was found to be 5.6 g/L. EC50 for algae was calculated to be ca. 26857mg/L
NOEC(mobility)was estimated to be 1.0 g/L and NOEC (condition)was estimated to be <1.0g/L
L-arginine did not show toxicity to mikroorganisms. The EC10 after 16h was>10g/L
Considering the results from higher trophic levels as well as for microorganisms and an expert statement 
(see endpoint summary in IUCLID section 6.1.5) toxicity testing with aquatic algae was not deemed necessary.
Fresh water fish :limit test according to OECD 203 did not show any adverse effects to fish at a test concentration of 1 g/L 
Fresh water invertebrates:A limit test according to OECD 202 did not show any adverse effects to Daphnia magna at a test 
concentration of 1 g/L L-arginine.
A subsequent test with L-arginine according to OECD 202 with higher test concentrations showed the following results:
EC50 = 1.8 g/L; EC100 = 5.6 g/L; NOEC (mobility) was estimated to be 1.0 g/L and NOEC (condition) was estimated to be < 1.0 g/L.

4.2.2.2-Irratıon-Corrosion
The instillation of L-arginine did not cause any changes at the rabbits eyes. The corneae, irises and conjunctivae were not affected
 by instillation of the test item. L-arginine is classified as not-irritating to eyes.

4.2.2.3- Sensitation
There is no human or animal data that indicates L-arginine to be a skin sensitiser. Considering the extensive, widespread dermal 
exposure to L-arginine in preparations repeatedly applied to the skin or being in contact with the skin, the absence of case reports 
of humans showing skin reactions is consistent with L-arginine having a very low skin sensitisation potential.

4.2.2.4- Repeated dose toxicity
The mean human daily intake of arginine for all life stage and gender groups from food and supplements is approximately 4.2 g/d 
(Food and Nutrition Board, 2005). A dietary dose of 5.0% L-arginine is equivalent to about 50 times amount of the mean daily 
oral intake for humans.

4.2.2.5- Genetic Toxicity
In a GLP guideline study according to OECD 473 L-arginine did not induce a statistically significant increase in the 
frequency of cellswith chromosome aberrations in either the absence or presence of a liver enzyme metabolising system in 
either of two separate experiments. The maximum test concentration was 1740 µg/L. The test material was therefore considered
 to be non-clastogenic to human lymphocytes in vitro.

4.2.2.6-Toxicity to Reproduction
L-arginine did not show effects on the reproductive organs in general repeated dose toxicity studies. Moreover, L-arginine 
is an amino acid that is required for normal functioning of humans. The substance is of very low toxicological activity and 
subject to homeostasis. Therefore, reprotoxic effects are not expected for L-arginine and no test is required for this 
substance.