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Toxicological information

Skin sensitisation

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Administrative data

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
Between 07 May 1992 and 02 July 1992
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results. However, as this study is used in a read-across approach Klimisch 2 is assigned.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1993
Report date:
1993

Materials and methods

Test guidelineopen allclose all
Qualifier:
equivalent or similar to guideline
Guideline:
other: OECD
Qualifier:
equivalent or similar to guideline
Guideline:
other: EPA-FIFRA
Qualifier:
equivalent or similar to guideline
Guideline:
other: EPA-TSCA
Qualifier:
equivalent or similar to guideline
Guideline:
other: Japanese-MAFF
GLP compliance:
yes
Type of study:
Buehler test

Test material

Constituent 1
Reference substance name:
75975-85-8
EC Number:
616-278-7
Cas Number:
75975-85-8
IUPAC Name:
75975-85-8
Test material form:
other: liquid
Details on test material:
Sponsor ID: 0S# 67708C (Total Base Number = 300)
Springborn ID: S92.007.3263
Receipt Date: March 31, 1992
Physical Description: Brown liquid
Storage Conditions: Room temperature
Expiration Date: None provided

In vivo test system

Test animals

Species:
guinea pig
Strain:
Hartley
Sex:
male/female
Details on test animals and environmental conditions:
Animals and Animal Husbandry
Animal housing and care were based on AAALAC standards and to those published in the Guide for the Care and Use of Laboratory Animals, NIH Publication No. 88-23.
Young adult Hartley Derived Albino guinea pigs were obtained from Harlan Sprague Dawley, Inc., Indianapolis, Indiana, for use in this study. The animals were individually housed in suspended stainless steel cages in an environment-controlled room with a 12/12 hour light/dark cycle. Purina Certified Guinea Pig Chow #5026 and purified water were provided to each animal ad libitum. The guinea pigs were individually identified using cage cards. All animals were acclimated to the laboratory environment for a minimum of five days prior to dosing. Only those animals judged to be healthy were assigned to the study. All range-finding study animals were weighed on the day prior to chamber application; main study animals were weighed on the day prior to the first induction and each subsequent chamber application at challenge and rechallenges.

Study design: in vivo (non-LLNA)

Inductionopen allclose all
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
100% as received, and 75%, 50% and 25% w/v OS# 67708C in USP grade mineral oil
Challengeopen allclose all
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
100% as received, and 75%, 50% and 25% w/v OS# 67708C in USP grade mineral oil
No. of animals per dose:
Phase/Group Males / Females
Topical Range-Finding: 2 / 2
Test Group: 5 / 5
Challenge Control Group: 5 / 5
Rechallenge Control Group: 5 / 5
Second Rechallenge Control Group: 5 / 5
DNCB Test Group: 3 / 3
DNCB Control Group: 2 / 1
Details on study design:
Fifty-three guinea pigs were assigned to the study.

Range-finding study
Irritation screen: A preliminary irritation screen was performed to determine an appropriate concentration of the test article for the standard sensitization study. The procedure was as follows:
On the day prior to dose administration, the hair was clipped from the dorsal trunk area of two male and two female guinea pigs using a small animal clipper. On the following day, four chambers at four different concentrations (100% as received, and 75%, 50% and 25% w/v OS# 67708C in USP grade mineral oil) were applied to the clipped area of each animal (one chamber for each level of test article). A dose of 0.3 mL of the freshly prepared test substance or test substance mixture was placed on a 25 mm Hilltop chamber. The chambers then were applied to the clipped surface as quickly as possible. The trunk of the animal was wrapped with elastic wrap and secured with tape to prevent removal of the chamber and the animal was returned to its cage.
Approximately six hours after dosing, the elastic wrap, tape and chambers were removed. The test sites were wiped with gauze moistened in USP grade mineral oil to remove test article residue and the animals returned to their cages. Approximately 24 and 48 hours following chamber application the test sites were graded using the following scale:
0 - No reaction
± - Slight patchy erythema
1 - Slight, but confluent or moderate patchy erythema.
2 - Moderate confluent erythema
3 - Severe erythema with or without edema

Induction phase: On the day prior to dose administration (day -1), the hair was then removed from the left side of ten test animals and six DNCB test animals with a small animal clipper. On the following day (day 1) a dose of 0.3 mL of the freshly prepared test solution was placed on a 25 mm Hilltop chamber. The chamber was then applied to the clipped surface of each animal as quickly as possible. Test animals received 100% OS# 67708C. The DNCB test animals received 0.5% w/v DNCB in acetone/ethanol. The trunk of each test animal was then wrapped with elastic wrap to prevent removal of the chamber and the animal returned to its cage. NOTE: The DNCB positive control group was utilized as a common control group for two other Modified Buehler Studies running concurrently for the Sponsor.
Approximately six hours after dosing, the elastic wrap and chamber were removed. The sites for the test animals were wiped with gauze moistened in USP grade mineral oil and the test sites for the DNCB animals were wiped with gauze moistened in distilled water to remove test article residue. The animals were returned to their cages. Test sites were graded for dermal irritation at approximately 24 and 48 hours following chamber application using the scale presented previously. The above induction and grading procedures were repeated for both the test and DNCB test animals on study day 8 and study day 15 so that a total of three consecutive induction exposures were made to the animals. The animals remained untreated after the last induction until the challenge phase of this study.

Challenge phase: On the day prior to challenge dose administration, the hair was clipped from the left side of the ten test and ten naive challenge control animals and the right side of the DNCB test and control animals with a small animal clipper. On day 29, a dose of 0.3 mL of the freshly prepared test substance mixture was placed on a 25 mm Hilltop chamber. The chamber was then applied to the clipped surface of each test and challenge control animal as quickly as possible. Test and challenge control animals received 50% w/v OS# 67708C in USP grade mineral oil. DNCB test and DNCB control animals received two 25 mm Hilltop chambers containing 0.1 % w /v or 0.2% w /v DNCB in acetone/ethanol. The trunk of each animal was then wrapped with elastic wrap in order to prevent removal of the chamber and the animal was returned to its cage.
Approximately six hours after dosing, the elastic wrap and chamber were removed. The OS# 67708C test sites were wiped with gauze moistened in USP grade mineral oil and the DNCB test sites were wiped with gauze moistened in distilled water to remove test article residue. The animals were then returned to their cages.
Approximately 20 hours after chamber removal the exposure sites were depilated using Neet Cream. The depilatory was placed on the test sites and surrounding areas and left on for no more than fifteen minutes. The depilatory was thoroughly removed with a stream of warm, running water. The animals were dried with a towel and returned to their cages. Approximately 24 and 48 hours after chamber removal, the test sites were graded using the scale presented previously.

Rechallenge phase: The rechallenge was performed on study day 37. On the day prior to rechallenge dose administration, the hair was removed from the right side of the ten test and ten naive rechallenge control animals with a small animal clipper. On the following day, a dose of 0.3 mL of the freshly prepared test substance mixture was placed on a 25 mm Hilltop chamber. The chamber was then applied to the clipped surface of each test and rechallenge control animal as quickly as possible. Test and rechallenge control animals received 25% w/v OS# 67708C in USP grade mineral oil. The trunk of each animal was then wrapped with elastic wrap in order to prevent removal of the chamber and the animal returned to its cage.
Approximately six hours after dosing, the elastic wrap and chamber were removed. The OS# 67708C test sites were wiped with gauze moistened in USP grade mineral oil and the animals were returned to their individual cages. Procedures for depilation and grading were the same as those described for challenge.

Second rechallenge phase: The rechallenge was performed on study day 43. On the day prior to rechallenge dose administration, the hair was removed from the right side of the ten test and ten naive rechallenge control animals with a small animal clipper. On the following day, a dose of 0.3 mL of the freshly prepared test substance mixture was placed on a 25 mm Hilltop chamber. The chamber was then applied to the clipped surface as
quickly as possible. Test and rechallenge control animals received 10% w/v OS# 67708C in USP grade mineral oil. The trunk of each animal was then wrapped with elastic wrap in order to prevent removal of the chamber and the animal returned to its cage. Approximately six hours after dosing, the elastic wrap and chamber were removed. The OS# 67708C test sites were wiped with gauze moistened in USP grade mineral oil and the animals were returned to their individual cages. Procedures for depilation and grading were the same as those described for challenge.

Study design: in vivo (LLNA)

Positive control substance(s):
other: 1-chloro-2,4-dinitrobenzene (DNCB)

Results and discussion

In vivo (non-LLNA)

Resultsopen allclose all
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
50% w/v OS#67708C in mineral oil
No. with + reactions:
9
Total no. in group:
10
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 50% w/v OS#67708C in mineral oil. No with. + reactions: 9.0. Total no. in groups: 10.0.
Reading:
2nd reading
Hours after challenge:
48
Group:
test chemical
Dose level:
50% w/v OS#67708C in mineral oil
No. with + reactions:
8
Total no. in group:
10
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 50% w/v OS#67708C in mineral oil. No with. + reactions: 8.0. Total no. in groups: 10.0.
Reading:
1st reading
Hours after challenge:
24
Group:
other: challenge control
Dose level:
50% w/v OS#67708C in mineral oil
No. with + reactions:
1
Total no. in group:
10
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: other: challenge control. Dose level: 50% w/v OS#67708C in mineral oil. No with. + reactions: 1.0. Total no. in groups: 10.0.
Reading:
2nd reading
Hours after challenge:
48
Group:
other: challenge control
Dose level:
50% w/v OS#67708C in mineral oil
No. with + reactions:
1
Total no. in group:
10
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: other: challenge control. Dose level: 50% w/v OS#67708C in mineral oil. No with. + reactions: 1.0. Total no. in groups: 10.0.
Reading:
1st reading
Hours after challenge:
24
Group:
other: DNCB
Dose level:
0.1% w/v DNCB in Acetone/Ethanol
No. with + reactions:
6
Total no. in group:
6
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: other: DNCB. Dose level: 0.1% w/v DNCB in Acetone/Ethanol. No with. + reactions: 6.0. Total no. in groups: 6.0.
Reading:
2nd reading
Hours after challenge:
48
Group:
other: DNCB
Dose level:
0.1% w/v DNCB in Acetone/Ethanol
No. with + reactions:
6
Total no. in group:
6
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: other: DNCB. Dose level: 0.1% w/v DNCB in Acetone/Ethanol. No with. + reactions: 6.0. Total no. in groups: 6.0.
Reading:
1st reading
Hours after challenge:
24
Group:
other: DNCB Controls
Dose level:
0.1% w/v DNCB in Acetone/Ethanol
No. with + reactions:
1
Total no. in group:
3
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: other: DNCB Controls. Dose level: 0.1% w/v DNCB in Acetone/Ethanol. No with. + reactions: 1.0. Total no. in groups: 3.0.
Reading:
2nd reading
Hours after challenge:
48
Group:
other: DNCB Controls
Dose level:
0.1% w/v DNCB in Acetone/Ethanol
No. with + reactions:
0
Total no. in group:
3
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: other: DNCB Controls. Dose level: 0.1% w/v DNCB in Acetone/Ethanol. No with. + reactions: 0.0. Total no. in groups: 3.0.
Reading:
1st reading
Hours after challenge:
24
Group:
other: DNCB
Dose level:
0.2% w/v DNCB in Acetone/Ethanol
No. with + reactions:
6
Total no. in group:
6
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: other: DNCB. Dose level: 0.2% w/v DNCB in Acetone/Ethanol. No with. + reactions: 6.0. Total no. in groups: 6.0.
Reading:
2nd reading
Hours after challenge:
48
Group:
other: DNCB
Dose level:
0.2% w/v DNCB in Acetone/Ethanol
No. with + reactions:
6
Total no. in group:
6
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: other: DNCB. Dose level: 0.2% w/v DNCB in Acetone/Ethanol. No with. + reactions: 6.0. Total no. in groups: 6.0.
Reading:
1st reading
Hours after challenge:
24
Group:
other: DNCB Controls
Dose level:
0.2% w/v DNCB in Acetone/Ethanol
No. with + reactions:
2
Total no. in group:
3
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: other: DNCB Controls. Dose level: 0.2% w/v DNCB in Acetone/Ethanol. No with. + reactions: 2.0. Total no. in groups: 3.0.
Reading:
2nd reading
Hours after challenge:
48
Group:
other: DNCB Controls
Dose level:
0.2% w/v DNCB in Acetone/Ethanol
No. with + reactions:
1
Total no. in group:
3
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: other: DNCB Controls. Dose level: 0.2% w/v DNCB in Acetone/Ethanol. No with. + reactions: 1.0. Total no. in groups: 3.0.
Reading:
rechallenge
Hours after challenge:
24
Group:
test chemical
Dose level:
25% w/v OS#67708C in mineral oil
No. with + reactions:
10
Total no. in group:
10
Remarks on result:
other: Reading: rechallenge. . Hours after challenge: 24.0. Group: test group. Dose level: 25% w/v OS#67708C in mineral oil. No with. + reactions: 10.0. Total no. in groups: 10.0.
Reading:
rechallenge
Hours after challenge:
48
Group:
test chemical
Dose level:
25% w/v OS#67708C in mineral oil
No. with + reactions:
10
Total no. in group:
10
Remarks on result:
other: Reading: rechallenge. . Hours after challenge: 48.0. Group: test group. Dose level: 25% w/v OS#67708C in mineral oil. No with. + reactions: 10.0. Total no. in groups: 10.0.
Reading:
rechallenge
Hours after challenge:
24
Group:
negative control
Dose level:
25% w/v OS#67708C in mineral oil
No. with + reactions:
4
Total no. in group:
10
Remarks on result:
other: Reading: rechallenge. . Hours after challenge: 24.0. Group: negative control. Dose level: 25% w/v OS#67708C in mineral oil. No with. + reactions: 4.0. Total no. in groups: 10.0.
Reading:
rechallenge
Hours after challenge:
48
Group:
negative control
Dose level:
25% w/v OS#67708C in mineral oil
No. with + reactions:
5
Total no. in group:
10
Remarks on result:
other: Reading: rechallenge. . Hours after challenge: 48.0. Group: negative control. Dose level: 25% w/v OS#67708C in mineral oil. No with. + reactions: 5.0. Total no. in groups: 10.0.
Reading:
other: second rechallenge
Hours after challenge:
24
Group:
test chemical
Dose level:
10% w/v OS#67708C in mineral oil
No. with + reactions:
7
Total no. in group:
10
Remarks on result:
other: Reading: other: second rechallenge. . Hours after challenge: 24.0. Group: test group. Dose level: 10% w/v OS#67708C in mineral oil. No with. + reactions: 7.0. Total no. in groups: 10.0.
Reading:
other: second rechallenge
Hours after challenge:
48
Group:
test chemical
Dose level:
10% w/v OS#67708C in mineral oil
No. with + reactions:
7
Total no. in group:
10
Remarks on result:
other: Reading: other: second rechallenge. . Hours after challenge: 48.0. Group: test group. Dose level: 10% w/v OS#67708C in mineral oil. No with. + reactions: 7.0. Total no. in groups: 10.0.
Reading:
other: second rechallenge
Hours after challenge:
24
Group:
negative control
Dose level:
10% w/v OS#67708C in mineral oil
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
other: Reading: other: second rechallenge. . Hours after challenge: 24.0. Group: negative control. Dose level: 10% w/v OS#67708C in mineral oil. No with. + reactions: 0.0. Total no. in groups: 10.0.
Reading:
other: second rechallenge
Hours after challenge:
48
Group:
negative control
Dose level:
10% w/v OS#67708C in mineral oil
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
other: Reading: other: second rechallenge. . Hours after challenge: 48.0. Group: negative control. Dose level: 10% w/v OS#67708C in mineral oil. No with. + reactions: 0.0. Total no. in groups: 10.0.

Any other information on results incl. tables

Body Weights: All animals appeared in good health throughout the study. Main study sensitization animals gained weight during the study.
Body weight Data
Group Animal Body Weight(g)
Number/Sex One Day Prior to Dosing
Range-Finding 8186/M 492
8187/M 470
8215/F 435
8216/F 403
 
Group Animal Body Weight {g)
Number/Sex Day -1 Day28 Day 36 Day 42
Test 8400/M 428 594 604 531
8401/M 444 614 627 640
8402/M 424 594 622 633
8403/M 419 534 548 550
8404/M 423 595 602 618
8510/F 419 534 550 544
8511/F 406 516 515 518
8512/F 449 489 497 453
8513/F 458 547 567 569
8514/F 433 637 652 640
Challenge Contrel 8405/M 433 666 - -
8406/M 450 625 - -
8407/M 441 660 - -
8408/M 452 708 - -
8409/M 433 675 - -
8515/F 396 534 - -
8516/F 428 550 - -
8517/F 400 515 - -
8518/F 436 597 - -
8519/F 431 552 - -
Rechallenge Controls 8410/M 419 - 621 -
8411/M 389 - 612 -
8412/M 403 - 652 -
8413/M 402 - 658 -
8414/M 373 - 758 -
8520/F 401 - 607 -
8521/F 406 - 550 -
8522/F 373 - 517 -
8523/F 413 - 571 -
8524/F 396 - 521 -
Second Rechallenge Controte 8415/M 425 - - 701
8416/M 410 - - 672
8417/M 470 - - 879
8418/M 452 - - 714
8419/m 440 - - 712
8525/f 425 - - 594
8526/F 402 - - 552
8527/F 435 - - 586
8528/F 417 - - 559
8529/F 414 - - 571
DNCB Test 8355/M 421 561 - -
8356/M 461 697 - -
8357/M 444 635 - -
8465/F 409 468 - -
8466/F 388 535 - -
8467/F 392 496 - -
DNCß Control 8358/F 439 681 - -
8359/M 412 599 - -
8468/F 419 537 - -
Topical Range-Finding: Based on these results, a test article dose of 100% was considered to be appropriate for induction, 50% was considered acceptable for challenge, 25% for rechallenge and 10% for the second rechallenge.
Table 2
Individual Range-Finding Scores
(OS# 67708C)
Treatment Animal Number/ Sex Dermal Scores
24 hr 48 hr
100% w/v OS# 67708C 8186/M ± ±
8187/M ± 0
8215/F 0 0
8216/F ± ±
75% w/v OS# 67708C in Mineral Oil 8186/M 0 0
8187/M ± 0
8215/F ± 0
8216/F ± 0
50% w/v OS# 67708C in Mineral Oil 8186/M 0 0
8187/M ± 0
8215/F ± 0
8216/F 0 0
25% w/v OS# 67708C in Mineral Oil 8186/M 0 0
8187/M 0 0
8215/F 0 0
8216/F 0 0
Sensitization Study: Induction Scores:
Table 3
Individual Induction Scores
(OS* 67708C)
Group Animal No./ Sex Dermal Scores
Induction 1* Induction 2* Induction 3*
24 Hr 48 Hr 24 Hr 48 Hr 24 Hr 48 Hr
Test 8400/M ± 0 0 0 ± 0
8401/M 0 0 0 0 ± ±
8402/M 0 0 ± 0 ± ±
8403/M 0 0 0 0 ± ±
8404/M 0 0 0 0 ± ±
8510/F 0 0 ± 0 ± ±
8511/F 0 0 ± 0 1 ±
8512/F 0 ± ± 0 1 ±
8513/F 0 ± 0 0 1 ±
8514/F 0 0 0 0 ± 0
*100% (as received) OS* 67708C.
Table 4
Individual Induction Scores
(DNCB)
Group Animal No./ Sex Dermal Scores
Induction 1* Induction 2* Induction 3*
24 Hr 48 Hr 24 Hr 48 Hr 24 Hr 48 Hr
DNCB Test 8355/M ± ± 3b,c 3b,c 3c, d 3b, c, d
8356/M ± ± 3b,c 3b,c 3b, d, e 3b,c
8357/M 1 1c 3b,c 3b,c 2c 3d, e
8465/F ± 2c 3b,c 3b,c 3b, c, d 3b, c, d
8466/F 1 1c 3b,c 3b,c 3b, c, d 3b, c, d
  8467/F ± ± 3b,c 3b,c 3b, c, d 3b, c, d
a0.5% w/v DNCB
bEschar
cSlinght edema
dblanching
eModerate edema
Challenge Scores:
Table 5
Individual Challenge Scores
(OS# 67708C)
Group Challenge Treatment Animal No./Sex Dermal Scores
24 Hr 48 Hr
Test 50%w/vOS# 67708C in USP Grade Mineral Oil 8400/M 1 1
8401/M 1 1a
8402/M ± ±
8403/M 1 1
8404/M 1 1
8510/F 1 1a
8511/F 1 ±
8512/F 1 1a
8513/F 1 1
8514/F 2a 2a
Mean 1.1 1.0
Challenge Controls 50%w/vOS# 67708C in USP Grade Mineral Oil 8405/M ± ±
8406/M ± ±
8407/M ± ±
8408/M ± 1
8409/M ± ±
8515/F ± ±
8516/F 1 ±
8517/F ± ±
8518/F 0 0
8519/F ± ±
Mean 0.5 0.5
aslight edema
bmoderate edema
csevere edema
NOTE: For the purpose af calculation, ± = 0.5.
Table 6
individual challenge Scores
{DNCB)
Group  Challenge Treatment Animal No./ Sex Dermal Scores
24 Hr  48 Hr
DNCB Test 0.1% w/v in Acetone/Ethanol 8355/M 3a, b 3a, b
8356/M 3a, c, d 3a, c, d
8357/M 3a, c, d 3a, c, d
8465/F 3a, b 3a, b
8466/F 3a, c 3a, c
8467/F 3a, b,d 3a, b,d
Mean 3.0 3.0
DNCB Controls 0.1% w/vin Acetone/Ethanol 8358/M 1 ±
8359/M ± ±
8968/F ± 0
Mean 0.7 0.3
DNCB Test 0.2% w/vin Acetone/Ethanol 8355/M 3a, b 3a, c, d
8356/M 3a, c, d 3a, c, d
8357/M 3a, c, d 3a, c, d
8465/F 3a, c 3a, c, d
8466/F 3a, c 3a, c
8467/F 3a, c, d 3a, c, d
Mean 3.0 3.0
DNCB Controls 0.2% w/v in Acetone/Ethanol 8358/M 1 1
8359/M ± ±
8968/F 1 ±
Mean 0.8 0.7
ablanching
bslight edema
cmoderate edema
deschar
NOTE: For the purpose of calculation, ± = 0.5
Rechallenge Scores:
Table 7
IndividualRechallenge Scores
(0S#67708C)
Group Challenge Treatment Animal No./Sex DermalScores
24 Hr 48 Hr
Test 25%w/v OS# 67708C In USP grademineral Oil 8400/M 1 2a
8401/M 2a 2a
8402/M 1 1
8403/M 1 1
8404/M 2a 2b
8510/F 2a 2b
8511/F 1 1
8512/F 2a 2a
8513/F 2a 2a
8514/F 2 2a
Mean 1.6 1.7
Rectialtenga Controls 25% w/v OS# 67708Cin USP Grade MineralOil 8410/M ± 1
8411/M ± 1
8412/M 1 1
8413/M ± ±
8414/M 1 1
8520/F ± ±
8521/F 1 ±
8522/F ± ±
8523/F 1 1
8524/F ± ±
Mean 0.7 0.8
aSlight edema
bModerate edema
NOTE: For the purpose af calculation, ± = 0.5.
Second Rechallenge Scores:
Table 8
Individual Second Rechallenge Scores
(OS# 67708C)
Group Challenge Treatment Animal No./ Sex Dermal Scores
24 Hr 48 Hr
Test 10% w/v OS# 6770GC irt usp Grede Mineral Oil 8400/M 1a 1a
8401/M 2a 2a
8402/M ± ±
8403/M 1 ±
8404/M 2b 2b
8510/F 1 1a
8511/F ± ±
8512/F 1 1
8513/F 1 1
8514/F 2a 2a
Mean 1.2 1.2
Fectiallenge Controls 1d% w/v 677DSC In dsp Grade Mineral Oil 8415/M ± ±
8416/M 0 ±
8417/M ± ±
8418/M 0 ±
8419/M ± ±
8525/F ± ±
8526/F ± ±
8527/F ± ±
8528/F 0 ±
8529/F 0 0
Mean 0.3 0.5
aSlight edema
bModerate edema
NOTE: For the purpose af calculation, ± = 0.5.
OS# 67708C: Following challenge with 50% w/v OS# 67708C in USP grade mineral oil, dermal scores of 1 to 2 were observed in 9/10 test animals at 24 hours. By 48 hours, dermal scores of 1 to 2 with the majority of the test sites exhibiting slight oedema were observed in 8/10 test animals. Dermal scores in 9/10 challenge control animals were 0 to ± at 24 and 48 hours. Group mean dermal scores were noted to be higher in the test animals as compared to the challenge control animals. Following rechallenge with 25% w/v OS# 67708C in USP grade mineral oil, a stronger dermal response was again noted in the test group as compared to the rechallenge control group. Dermal scores of 1 to 2 with the majority of the test sites exhibiting slight to moderate oedema were noted in 10/10 test animals at 24 and 48 hours. Dermal reactions in 10/10 rechallenge control animals were scores of ± to 1 at 24 and 48 hours. Group mean dermal scores were also higher in the test animals as compared to the rechallenge control animals. Following the second rechallenge with 10% w/v OS# 67708C in USP grade mineral oil, dermal scores of 1 to 2 with the majority of the test sites exhibiting slight to moderate oedema were again noted in 8/10 test animals at 24 hours and 7/10 test animals at 48 hours. Dermal scores of 0 to ± were noted in the 10/10 control animals at 24 and 48 hours. The number of animals exhibiting positive sensitzation responses for the test substance at 50%, 25%, and 10% were 8/10, 10/10, and 7/10 respectively, and the mean 24/48 hour Draize scores were 1.1/2.1, 1.6/1.7, and 1.2/1.2, respectively. The mean 24/48 hour Draize scors for the naive controls at 50%, 25%, and 10% were 0.5/0.5, 0.7/0.8, and 0.3/0.5, respectively. Positve control: Challenge with DNCB produced substantially stronger dermal responses in animals previously induced with the positive control demonstrating that the test system could detect potential contact sensitizers.

Applicant's summary and conclusion

Interpretation of results:
sensitising
Remarks:
Migrated information Under the conditions of this test, OS# 67708C is considered a contact sensitizer in guinea pigs.
Conclusions:
Under the conditions of this test, OS# 67708C (Total Base Number = 300) is considered a contact sensitizer in guinea pigs.
Executive summary:

The potential of the calcium sulfonate read across substance (CAS 75975-85-8, Total Base Number = 300) to elicit a delayed contact hypersensitivity response was evaluated in guinea pigs. Five male and five female guinea pigs were treated topically with 100% of the test substance, once per week, for three consecutive weeks. Following a two week rest period, the ten test animals and ten previously untreated (naive) challenge control guinea pigs were topically challenged with 50% w/v of the test substance in USP grade mineral oil. Challenge responses in the test animals were compared to those of the challenge controls. Approximately one week after challenge, the ten test animals and ten previously untreated (naive) rechallenge control guinea pigs were topically rechallenged with 25% w/v ofthe test substance in USP grade mineral oil. Rechallenge responses in the test animals were compared to those of the rechallenge controls. Approximately one week after rechallenge, a second rechallenge was performed with 10% w/v ofthe test substance in USP grade mineral oil using the ten test animals and ten new naive second rechallenge control animals in order to confirm previous challenge results. Second rechallenge responses in the test animals were compared to those of the second rechallenge controls.

A dinitrochlorobenzene (DNCB) positive control group consisting of six DNCB test and three DNCB control guinea pigs was included in this study. The DNCB test animals received 0.5% w/v DNCB in an acetone/ethanol vehicle for induction and 0.1% w/v and 0.2% w/v DNCS in acetone/ethanol for challenge.

Evidence of delayed contact dermal sensitization was observed following the challenge and two rechallenges with the test substance. Slight to moderate dermal reactions (grades ± to 2) were observed for the test animals at both the 24 and 48 hour scoring intervals. No to slight reactions (grades 0 to 1) were observed for the challenge control animals at both the 24 and 48 hour scoring intervals. The 24 and 48 hour group mean scores were higher in test animals than in the challenge control animals. For both rechallenges. the test animals exhibited greater dermal responses to the test article than either of the naive rechallenge control groups.

Challenge with DNCB produced substantially stronger dermal responses in animals previously induced with the positive control demonstrating that the test system could detect potential contact sensitizers.

Based on the results of this study, the calcium sulfonate read across substance (CAS 75975-85-8) is considered a contact sensitizer in guinea pigs.