Dibutoxydibutylstannane

Carcinogenicity

Description of key information

The following study has been submitted to address the carcinogenicity endpoint:
EFSA (2004) Opinion of the Scientific Panel on Contaminants in the Food Chain on a request from the Commision to assess the health risks to consumers associated with exposure to organotins in foodstuffs (Question No EFSA-Q-2003-110). The EFSA Journal 102: 1-119.
As the reference is secondary literature, it has been allocated a Klimisch score of 4.

Key value for chemical safety assessment

Carcinogenicity: via oral route

Link to relevant study records

Reference

Endpoint:

carcinogenicity: oral

Type of information:

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

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Scientific opinion of EFSA citing numerous studies on toxicological effects of oganotin compounds. The Committee preparing the document primarily focused on compounds for which both the toxicological and exposure databases were considered suitable. Data used in the assessment is cited only as short abstracts, and it is therefore not possible to evaluate the reliability of the individual studies reviewed in the document.

Principles of method if other than guideline:

Data reviewed and cited by EFSA in a publically available report addressing the potential effects of organotin concentration in food. Reference is made to a chronic (2 year) carcinogenicity study from NCI (1979) in which F344 rats and B6C3F1 mice were fed diets containing dibutyltin diacetate. Rats were dosed with 66.5 and 133 mg/kg dibutyltin diacetate and the mice were fed diets containing 76 and 152 mg/kg dibutyltin diacetate. Groups of 50 males and 50 females of each species were used. Data cited from: NCI (National Cancer Institute), 1979. Carcinogenesis. Bioassay of dibutyltin diacetate for possible carcinogenicity. Technical Report Series n. 183. US-NIH.

GLP compliance:

not specified

Species:

other: Rat and Mouse

Strain:

other: F344 Rats and B6C3F1 mice

Sex:

male/female

Route of administration:

oral: feed

Vehicle:

not specified

Analytical verification of doses or concentrations:

not specified

Remarks:

Doses / Concentrations:
66.5 and 133 mg/kg dibutyltin diacetate in F344 rats
Basis:

Remarks:

Doses / Concentrations:
76 and 152 mg/kg dibutyltin diacetate in B6C3F1 mice
Basis:

Control animals:

yes

Statistics:

Results were tested for statistical significance in comparison to controls

Details on results:

No statistically significant increased in tumour incidences were observed in dosed rats or mice compared to the control. An accidental loss of tissues from high dose female rats prevented an evaluation of the carcinogenicity of dibutyltin diacetate in female rats.

Dose descriptor:

NOAEL

Effect level:

133 ppm

Based on:

test mat.

Sex:

male

Basis for effect level:

other: No increased tumours up to the top dose (133 ppm in the diet) in males

Remarks on result:

other: Effect type: carcinogenicity (migrated information)

Dose descriptor:

NOAEL

Effect level:

152 ppm

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No increased incidence of tumours in mice up to the top dose (152 ppm in the diet)

Remarks on result:

other: Effect type: carcinogenicity (migrated information)

Conclusions:

In a two year carcinogenicity study performed in F344 rats and B6C3F1 mice, no increase in the incidence of tumours was noted in either species up to the highest dose tested.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

0.025 mg/kg bw/day

Study duration:

chronic

Species:

other: mouse and rats

Carcinogenicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Carcinogenicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

No data is available for the substance itself. Limited data from a presumably robust study indicated dibutyltin diacetate not to be carcinogenic in mice or in male rats; data for female rats was compromised by loss of tissues and no conclusion can be drawn.

A read-across approach was considered appropriate between dibutyltins. Under gastric conditions dibutyltins are hydrolysed to form dibutyltin chloride. This is demonstrated in various dibutyltin compounds presented in the TNO report V5047, (presented as individual reports as under Toxicokinetics).