Registration Dossier

Administrative data

Endpoint:
dermal absorption in vivo
Type of information:
migrated information: read-across based on grouping of substances (category approach)
Adequacy of study:
supporting study
Study period:
1982
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:
study report
Title:
Unnamed
Year:
1982
Report Date:
1982

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
The substance was applied to the shaved back skin of rats. The animals were housed in metabolic cages to collect urine and faeces. After 48 h the rats were euthanised and the substance was measured in urine and faeces, in the skin of the application area and in the remaining body.
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
not specified
Radiolabelling:
yes
Remarks:
14C

Test animals

Species:
rat
Strain:
Wistar
Sex:
male
Details on test animals and environmental conditions:
weight: 220-260 g
caging in open metabolic cages at a room temperature of 20 °C
feed (Altromin 1324) and water ad libitum

Administration / exposure

Type of coverage:
other: glass capsule with holes, allows gas exchange but prevents the rats to lick off the substance
Vehicle:
water
Duration of exposure:
48 h
Doses:
0.2 g of a 1 % solution
No. of animals per group:
10
Control animals:
no

Results and discussion

Signs and symptoms of toxicity:
not specified
Dermal irritation:
not specified
Total recovery:
81.5 %
Percutaneous absorption
Dose:
0.1 %
Parameter:
percentage
Absorption:
0.46 %
Remarks on result:
other: 48 h

Any other information on results incl. tables

The absorbed radioactivity was mostly eliminated via faeces (0.082 %), while a minor part was eliminated via urine (0.025 %). Elimination via faeces was similar in both collection periods (0 - 24 h and 24 - 48 h), while elimination via urine was predominantly found in the first collection period. After 48 h a mean of 0.339 % of the applied radioactivity could be found in the remaining carcass.

Applicant's summary and conclusion

Conclusions:
The absorption of sodium HEDP is very low (0.46 %).
Executive summary:

Cutaneous absorption and elimination of sodium HEDP was determined in male rats. The measurements were performed with 14C labelled CA 2. The radioactive substance was applied as a 1 % solution to the shaved back skin of rats. Absorption and elimination was measured after 48 h. After this time, 0.46 % of the applied radioactivity was absorbed. This shows that sodium HEDP is absorbed poorly. The main route of elimination was via faeces. Most of the absorbed amount (0.34 %) could be found in the remaining carcass (excluding the skin of the application area) at the end of the test. This may suggest a delayed elimination and probably an accumulation in the bones.