[No public or meaningful name is available]

Additional toxicological data

Administrative data

Endpoint:

additional toxicological information

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

No data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Meets generally accepted scientific standards with acceptable restrictions.

Data source

Reference

Reference Type:

publication

Title:

The ototoxic effect of boric acid solutions applied into the middle ear of guinea pigs.

Author:

Öztürkcan S, Dündar R, Katilmiş H, İlknur AE, Aktaş S & Haciömeroğlu S.

Year:

2009

Bibliographic source:

Eur. Arch. Otorhinolaryngol. 266: 663 - 667.

Materials and methods

Type of study / information:

The study analysed the ototoxic effects of boric acid solutions on 22 young guinea pigs.

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

The study analysed the ototoxic effects of boric acid solutions on 22 young guinea pigs. Auditory Brainstem Response (ABR) test was applied prior to adminsitration. A perforation was created on the tympanic membrane of the right ear and small gelfoam pieces were inserted into the perforation. Test solutions were administered for 10 days by means of a transcanal route. 15 days after insertion of the gelfoams they were removed and the ABR repeated.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Boric acid

EC Number:

233-139-2

EC Name:

Boric acid

Cas Number:

10043-35-3

Molecular formula:

H3BO3

IUPAC Name:

Boric acid

Results and discussion

Any other information on results incl. tables

When the saline control group and the 4 % boric acid solution prepared with distilled water group were compared against the initial condition of both groups, a borderline significance was detected (P = 0.046; P = 0.046, respectively). When the ototoxic control (Gentamicine) and 4 % boric acid solution prepared with 70 % alcohol groups were compared against their initial conditions, statistically signifcant changes in the ABRs threshold was found (P = 0.026; P = 0.011, repectively). When the ototoxic control group was compared with the 4 % boric acid solution prepared with distilled water and with the saline group, a statistically significant toxic effect was found in the ototoxic control group ( P = 0.003; P = 0.001, respectively). When the Gentamicine group was compared with 4 % boric acid solution prepared with 70 % alcohol group, no significant difference in ototoxic effect was detected between the two groups (p = 0.128).

As a result of the comparison of the 4 % boric acid solution prepared with 70 % alcohol group with the saline group and the 4 % boric acid prepared with distilled water groups statistically significant effect in the 4 % boric acid solution prepared with 70 % alcohol was detected (P = 0.002 ; P = 0.000). No statistically significance was found in comparison of the saline and 4 % boric acid solution prepared with distilled water groups (P: 0.653). In the group where 4 % boric acid solutions prepared with 70 % alcohol statistically significant alterations in the test thresholds were detected.

Applicant's summary and conclusion

Conclusions:

The study analysed the ototoxic effects of boric acid solutions on 22 young guinea pigs. Prior to application of the boric acid solution under general anaesthesia an Auditory Brainstem Response (ABR) test was applied to the right ear of the guinea pigs. Following the test a performation was created on the tympanic membrane of the right ear of each guinea pig and small gelfoam pieces inserted into the perforated area. Test soluitons were administered to the middle ear for 10 days by means of a transcanal route. 15 days after inserting the gelfoams they were removed and the ABR test performed again. The ABRs were within the normal range before applications after hte application no singificant changes were deteced in the ABRs threshold in the saline group or the group administered boric acid and dstilled water solution. However, significant changes were detected in the ototoxic control group (Gentamicine) and boric acid and alcohol solution groups.