Myo-inositol

Long-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

8 weeks

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

publication

Title:

Dietary Inositol Requirement for Juvenile Grass Shrimp, Penaeus monodon

Author:

Shiau S-Y and Su S-L

Year:

2004

Bibliographic source:

Aquaculture, 241:1-8

Materials and methods

Test guideline

Qualifier:

no guideline available

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Myo-inositol

EC Number:

201-781-2

EC Name:

Myo-inositol

Cas Number:

87-89-8

Molecular formula:

C6H12O6

IUPAC Name:

cyclohexane-1,2,3,4,5,6-hexol

Test material form:

solid

Details on test material:

- Purity: not reported

Sampling and analysis

Analytical monitoring:

yes

Test organisms

Test organisms (species):

other: Grass shrimp, Penaeus monodon

Study design

Test type:

other: Feeding study

Limit test:

no

Total exposure duration:

8 wk

Post exposure observation period:

None

Test conditions

Hardness:

not reported

Test temperature:

26 to 29°C

pH:

6.6 to 6.8

Dissolved oxygen:

Averaged at 7.3 mg O2/L

Salinity:

19 to 21 g/kg

Conductivity:

not reported

Nominal and measured concentrations:

Nominal: 250, 500, 1000, 2000, 4000. 6000, and 8000 mg/kg of diet
Analytical: 295, 696, 1079, 2036, 3943, 6159, and 8218 mg/kg of diet

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Key result

Duration:

8 wk

Dose descriptor:

LC50

Effect conc.:

>= 8 000 other: mg/kg diet

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: The survival data indicated that there was a gradual attrition during the 8-week duration of the experiment.

Details on results:

Weight gain, protein efficiency ratio and survival were highest for shrimp fed diets supplemented with ≥ 3943 mg/kg, followed by 2036 mg/kg and lowest for shrimp fed diets supplemented with ≤ 696 mg/kg. The values for these three dietary treatments were significantly different from one another (P<0.05). The survival data indicated that there was a gradual attrition during the 8-week duration of the experiment.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Shrimp fed diets supplemented with ≥3943 mg/kg (≥4000 mg/kg nominal) of diet had significantly (P<0.05) survival.

Executive summary:

The dietary test substance requirement of juvenile grass shrimp, Penaeus monodon, was estimated. Purified basal diets were formulated using vitamin-free casein as the protein source. Dietary treatments consisted of graded levels (0, 250, 500, 1000, 2000, 4000, 6000 and 8000 mg/kg of diet) of the test substance added to a basal diet. Each diet was fed to three replicate groups of shrimp initially averaging 0.44±0.01 g for 8 weeks. Shrimp fed diets supplemented with ≥3943 mg/kg of diet had significantly (P<0.05) greater weight gain, protein efficiency ratio (PER), survival and levels of the test substance in the midgut gland than those fed diets supplemented with ≤2036 mg/kg of diet. Lipid in the midgut gland of shrimp fed diets supplemented with ≥1079 mg/kg of diet was higher than that of shrimp fed diets supplemented with ≤696 mg/kg of diet. The midgut gland index (MGI) of shrimp fed diets supplemented with ≥3943 mg/kg of diet was lower than that of shrimp fed diets containing ≤1079 mg/kg of diet. Weight gain percentage, the level of test substance in the midgut gland and the midgut gland index values for the different treatments were analyzed by broken-line regression and indicated that the requirement for dietary test substance in growing P. monodonis was approximately 3400 mg/kg of diet.