Ceratonia siliqua, ext.

Long-term toxicity to fish

Administrative data

Endpoint:

long-term toxicity to fish, other

Remarks:

protective effect of carob (and fig) on lead induced toxicity in fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

90 days

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Remarks:

proper control and experimental design

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

other: 90-day long term exposure

Version / remarks:

LC50 was carried out according to Behreus and Karbeur, 90 day study is scientifically sound

Deviations:

not specified

Remarks:

Scientifically sound study design

Principles of method if other than guideline:

The extraction process was done according to Mokhtari et al. (2012),

GLP compliance:

not specified

Remarks:

Anticipated GLP was followed, though not specified in the report.

Test material

Test material information

Constituent 1

Test material form:

liquid

Details on test material:

- Physical appearance: Dark brown to black liquid
- Storage of test material: At room temperature

Specific details on test material used for the study:

Ceratonia siliqua pods (carob) (one kg) were collected from market and then separately crushed with seeds removal. Consequently, they were dried and grinded to a fine powder. The powder was solved in two liters of ethyl alcohol (100%) for 48 h with periodical shaking and then the extract was filtered using gauze and funnel. Subsequently, the ethyl alcohol was evaporated by rotatory evaporator and then the extract was lyophilized. The lyophilized sample semisolid mass (10%) was collected, stored in airtight containers and kept in refrigerator at 4oC. The extraction process was done according to Mokhtari et al.

Sampling and analysis

Analytical monitoring:

not specified

Details on sampling:

Blood samples were collected from caudal vein of fish using sterile syringe with EDTA solution (anticoagulant) at 30, 60 and 90 days post exposure for determining endpoints

Test solutions

Vehicle:

not specified

Remarks:

From paper no vehicle is indicated.

Test organisms

Test organisms (species):

other: O. niloticus

Details on test organisms:

One hundred and forty O. niloticus (30±10 g) free from diseases were collected from fish farm belonging to the Central Laboratory for Aquaculture Research. Fish were left two weeks for acclimatization before the beginning of the experimental study. Fish was fed on normal basal diet at 3% of body weight daily during the acclimation period. They were divided into 7 groups each contain two aquaria with 10 fish/aquarium.

Study design

Test type:

not specified

Water media type:

not specified

Limit test:

no

Total exposure duration:

90 d

Remarks on exposure duration:

variable exposure to protective materials

Test conditions

Hardness:

not specified

Test temperature:

not specified

pH:

not specified

Dissolved oxygen:

not specified

Salinity:

not specified

Conductivity:

not specified

Nominal and measured concentrations:

not specified

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Duration:

90 d

Dose descriptor:

other: 600 mg

Remarks:

1/2 and 1/4 LC50 of lead was given in conjunction with the carob to determine if carob was protective aginst lead exposure.

Effect conc.:

ca. 600 other: mg

Nominal / measured:

not specified

Conc. based on:

not specified

Basis for effect:

not specified

Remarks on result:

other: fish treated with lead and carob showed decrease mortality and all other endpoints were similar to those of the control

Details on results:

see attached paper

Results with reference substance (positive control):

Fish treated with just lead showed higher toxic effects and endpoints

Reported statistics and error estimates:

Means within the same column carrying different superscripts were significantly different at P < 0.05.

Any other information on results incl. tables

see paper attached

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Carob extract was protective against lead induced toxicity, indicating it is not an inherently toxic material itself. The hematological, biochemical parameters, growth performance were significantly decreased after exposure to 1/2 96h LC50 and 1/4 96h LC50 of Lead for 30, 60 or 90 days. Plasma glucose and mortality were increased significantly. Compared to control group, there were no significant changes in RBCs, Hb and PCV of fish fed with diet enriched with Carob or fig extract 600 mg/kg diet for 90 days in the presence of 1/2 96h LC50 or 1/4 96h LC50 of Lead.

Executive summary:

The current study aimed to investigate the possible effect of Ceratonia siliqua (carob) pods and Ficus carica (fig) fruits ether extracts against lead toxicity on hematological, biochemical parameters, growth performance and mortality % in Nile Tilapia (Oreochromis niloticus). One hundred and forty fish were divided into 7 groups. The first group was left as a control and fed a control diet, while, the second and third groups were exposed to 1/2 96 h LC50 (77.5 mg/L) and 1/4 96 hLC50 (38.7 mg/L) of Lead (Pb), respectively and provided with a control diet. The fourth and fifth groups were exposed to 1/2 96 h LC50 and 1/4 96 h LC50 of Pb, respectively and fed diet with 600 mg carob extract/kg diet. The sixth and seventh group were exposed to 1/2 96 h LC50 and 1/4 96 h LC50 of Pb, respectively and provided with diet contain 600 mg fig extract/kg diet. The hematological, biochemical parameters and growth performance was significantly decreased after exposure to 1/2 96 h LC50 and 1/4 96 hLC50 of Pb for 30, 60 and 90 days, while plasma glucose and mortality % were increased significantly. There were no significant changes in RBCs, Hb and PCV of O. niloticus exposed to 1/2 96 h LC50 and 1/4 96 h LC50 of Pb that fed diet enriched with carob extract 600 mg/kg diet for 90 days. The fish exposed to 1/2 96 h LC50 and 1/4 96 h LC50 of Pb and fed diet enriched with 600 mg/kg diet carob or fig for 90 days revealed no significant changes in plasma albumin, total protein, glucose and growth parameters with a reduction of mortality %. The current study highlighted the importance of carob and fig ether extract in the protection of Nile tilapia against the lead acetate toxicity.