Reaction products of γ-butyrolactone, naphthalene-1,6-diol and phthalic anhydride

Endpoint summary

Description of key information

Acute toxicity has been tested with the solid commercial material of the form in its stable structue at pH 10 in 1978. If brought into the acidic environment of the stomach acid, the material is transformed to the target substance.

Testing was done prior to the introduction of GLP and OECD testing guidelines. The method for acute oral toxicity is identical to the set-up outlined in OECD guideline 423. Doses of 2150 and 5000 mg/kg bw was tested in each five female and five male rats, and one female rat died one day after dosing with 5000 mg/kg bw. The other animals recovered and survived until the scheduled sacrifice 14 days after dosing. Therefore, the LD50 was determined to be greater than 5000 mg/kg bw in female rats. Animals of both dose groups had blue faeces and urine during the first 24h after dosing. Clincial symptomes were observed on the first day only. There were no findings at necropsy.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
The target chemical is a pH-indicator: It undergoes a reversible change in chemical structure (and accordingly the colour) depending on the pH value. The source chemical is the form that is predominant above pH 10. If given by the oral route, the source chemical is transformed to the target chemical in the acidic environment of the body. The reaction and comparison to similar pH indicators is shown in the figure.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
It is referred to the attached document.


3. ANALOGUE APPROACH JUSTIFICATION
Under the acidic conditions in the stomach, the source substance is transformed into the target substance. Therefore, for the oral route, both substance and source substances have identical toxicological profiles.

Reason / purpose for cross-reference:

read-across source

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Remarks on result:

other: No mortality up to 2000 mg/kg bw

Interpretation of results:

GHS criteria not met

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating dose

Value:

2 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available