Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.

REACH

N,N’-di[3-(p-toluene sulfonyl)oxy]phenyl urea

EC number: 876-151-9 | CAS number: 2292123-68-1

Life Cycle description
Uses advised against

Toxicological information

Endpoint summary

Administrative data

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

The substance has been tested for gene mutation/chromosome aberrations using in vitro methods.

In an in vitro gene mutation test conducted with bacteria in accordance with OECD Guideline 471, the substance was reported to be negative. This indicates that the substance does not exhibit gene mutation in bacteria under conditions of the test.

In an in vitro chromosome aberration test conducted on mammalian cells accordance with OECD Guideline 473, the substance was reported to be positive. This indicates that the substance may have potential for clastogenicity in vivo systems.

The in vitro gene mutation assay on bacteria has been selected as the key endpoint as the in vitro chromosome aberration study has been investigated in an in vivo system and the result of the in vivo micronucleus test was negative.

Link to relevant study records

Reference

Endpoint:: in vitro gene mutation study in bacteria
Type of information:: experimental study
Adequacy of study:: key study
Reliability:: 1 (reliable without restriction)
Rationale for reliability incl. deficiencies:: guideline study
Qualifier:: according to guideline
Guideline:: OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Version / remarks:: July 21, 1997
Deviations:: no
GLP compliance:: yes (incl. QA statement)
Type of assay:: bacterial reverse mutation assay
Species / strain / cell type:: S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2
Metabolic activation:: with and without
Metabolic activation system:: Rat liver S9 mix
Test concentrations with justification for top dose:: Main test -1 (-/+S9 mix): 4.88, 19.5, 78.1, 313, 1250, 5000 µg/plate.
Main test -2 (-/+ S9 mix): 313, 625, 1250, 2500, 5000 µg/plate.
5000µg/plate selected as the highest dose as precipitation of the test item was observed.
Vehicle / solvent:: - Vehicle(s)/solvent(s) used: DMSO

- Justification for choice of solvent/vehicle: The test item was insoluble in distilled water at 50 mg/mL. Test item solution of 50 mg/mL was prepared in DMSO. The test item was soluble and considered to be stable from the observations; no colour change, gas generation, etc. Dehydrated DMSO was selected as vehicle as the test item can hydrolyse with strong alkali.
Negative solvent / vehicle controls:: yes
Positive controls:: yes
Positive control substance:: sodium azide; benzo(a)pyrene; furylfuramide; other:
Remarks:: 5 positive controls are used
Details on test system and experimental conditions:: NUMBER OF REPLICATIONS:
- Number of cultures per concentration (single, duplicate, triplicate): triplicate
- Number of independent experiments: 2

METHOD OF TREATMENT/ EXPOSURE:
- preincubation; incorporation in agar and poured on to agar plate

TREATMENT AND HARVEST SCHEDULE:
- Preincubation period, if applicable: 20 minutes at 37°C +/- 0.5°C
- Exposure duration/duration of treatment: Incubation period = 48 hours
- Number of revertant colonies counted after incubation period

METHODS FOR MEASUREMENT OF CYTOTOXICITY
- Any supplementary information relevant to cytotoxicity: none observed
Rationale for test conditions:: As required by the OECD guideline
Evaluation criteria:: - Test item was judged to be positive when the number of revertant colonies increased to twice or more than the negative control and when the responses were dose-related and/or reproducible. The other cases were judged to be negative.
Statistics:: No statistical methods used
Species / strain:: S. typhimurium TA 100
Metabolic activation:: with and without
Genotoxicity:: negative
Cytotoxicity / choice of top concentrations:: no cytotoxicity, but tested up to precipitating concentrations
Vehicle controls validity:: valid
Untreated negative controls validity:: not applicable
True negative controls validity:: not applicable
Positive controls validity:: valid
Species / strain:: S. typhimurium TA 1535
Metabolic activation:: with and without
Genotoxicity:: negative
Cytotoxicity / choice of top concentrations:: no cytotoxicity, but tested up to precipitating concentrations
Vehicle controls validity:: valid
Untreated negative controls validity:: not applicable
True negative controls validity:: not applicable
Positive controls validity:: valid
Species / strain:: E. coli WP2 uvr A
Metabolic activation:: with and without
Genotoxicity:: negative
Cytotoxicity / choice of top concentrations:: no cytotoxicity, but tested up to precipitating concentrations
Vehicle controls validity:: valid
Untreated negative controls validity:: not applicable
True negative controls validity:: not applicable
Positive controls validity:: valid
Species / strain:: S. typhimurium TA 98
Metabolic activation:: with and without
Genotoxicity:: negative
Cytotoxicity / choice of top concentrations:: no cytotoxicity, but tested up to precipitating concentrations
Vehicle controls validity:: valid
Untreated negative controls validity:: not applicable
True negative controls validity:: not applicable
Positive controls validity:: valid
Species / strain:: S. typhimurium TA 1537
Metabolic activation:: with and without
Genotoxicity:: negative
Cytotoxicity / choice of top concentrations:: no cytotoxicity, but tested up to precipitating concentrations
Vehicle controls validity:: valid
Untreated negative controls validity:: not applicable
True negative controls validity:: not applicable
Positive controls validity:: valid
Conclusions:: The test item had no ability to induce mutations under the test conditions.

Endpoint conclusion

Endpoint conclusion:: no adverse effect observed (negative)

Genetic toxicity in vivo

Description of key information

In an in vivo micronucleus test was conducted with mice in accordance with OECD Guideline 474, the substance was reported to be negative. This indicates that the substance does not exhibit clastogenicity in mice under conditions of the test.

The results from this study remove the concern which was raised with the positive result in the in vitro chromosome aberration study.

Link to relevant study records

Reference

Endpoint:: in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus
Type of information:: experimental study
Adequacy of study:: key study
Reliability:: 1 (reliable without restriction)
Rationale for reliability incl. deficiencies:: guideline study
Qualifier:: according to guideline
Guideline:: OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
Version / remarks:: July 29, 2016
Deviations:: no
GLP compliance:: yes (incl. QA statement)
Type of assay:: mammalian erythrocyte micronucleus test
Species:: mouse
Strain:: ICR
Remarks:: Crl:CD1
Details on species / strain selection:: As required by the guideline. Mice are used widely in micronucleus test because the observation of the micronuclei is easy and the historical data are abundant
Sex:: male/female
Details on test animals or test system and environmental conditions:: TEST ANIMALS
- Source: Charles River Laboratories, Japan
- Age at study initiation: 7 weeks
- Weight at study initiation: male (26.5 - 31.3g), female (23.0 - 24.0g)
- Assigned to test groups randomly: yes, under following basis: body weight stratified random sampling method on the day before administration
- Fasting period before study: Not applicable
- Housing: Polycarbonate cages with flat bottom, bedding and enrichment
- Diet (e.g. ad libitum): MF pellets. ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 6 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21-25
- Humidity (%): 40-70
- Air changes (per hr): 10-15 times/hour
- Photoperiod (hrs dark / hrs light): 12 hours/12 hours
Route of administration:: oral: gavage
Vehicle:: Corn oil
Details on exposure:: PREPARATION OF DOSING SOLUTIONS:
The test item (4.00g) was weighed and suspended in corn oil using a laboratory mixer and ultrasonicator to make a 20 mL of 200mg/mL test item formulation. This formulation was serially diluted with corn oil to prepare 100 and 50.0 mg/mL test item formulations using a magnetic stirrer.

The test item formulations were prepared on the first administration day, stored within a cold place and used within 2 days after preparation.
Duration of treatment / exposure:: Not applicable for dosing by gavage.
Frequency of treatment:: 2 doses in a single 24 hour period.
Post exposure period:: 1 hour after second dose.
Dose / conc.:: 500 mg/kg bw/day (nominal)
Remarks:: Low dose
Dose / conc.:: 1 000 mg/kg bw/day (nominal)
Remarks:: Mid-dose
Dose / conc.:: 2 000 mg/kg bw/day (nominal)
Remarks:: High dose
No. of animals per sex per dose:: Low dose - 5 males
Mid-dose - 5 males
High dose - 5 males, 3 females
Control animals:: yes, concurrent no treatment; yes, concurrent vehicle
Positive control(s):: Mitomycin C (MMC)
- Justification for choice of positive control: MMC is lasted as a positive control in the OECD guideline and historical data have been accumulated in the testing facility.
- Route of administration: intraperitoneally
- Doses / concentrations: 2 mg/kg/day
Tissues and cell types examined:: Polychromatic erythrocytes (PCE)
Bone marrow erythrocytes (TE)
Details of tissue and slide preparation:: CRITERIA FOR DOSE SELECTION: Based on the results of the 28-day repeated dose oral toxicity study of the item. No toxic effect was observed on male or female SD rats administered 1000 mg/kg/day (oral gavage).

TREATMENT AND SAMPLING TIMES ( in addition to information in specific fields):
Specimens were prepared 24 hours after the second administration in the test item groups. Two specimens per animal were prepared.

DETAILS OF SLIDE PREPARATION:
The animals were euthanised. The femurs were removed and bone marrow cells were collected with approx. 0.8mL of heat-inactive foetal bovine serum into a centrifuge tube, the tube was centrifugated at 1000rpm for 5 minutes. A small amount of the cell suspension was smeared on the glass slide. The smears were completely air-dried and fixed with methanol. Then, the specimen were stained with 3 vol% Giemsa solution prepared with 1/15 mol/L phosphate buffer solution (pH 6.8) and treated with 0.004 w/v% citrate aqueous solution.

METHOD OF ANALYSIS:
The specimens of the untreated, the negative and positive controls and all three doses of the test item groups were observed. Slide number were allocated randomly to the specimens. The specimens were microscopically (x1000) in a blinded manner.
1) Frequency of micronuclei
four thousand polychromatic erythrocytes (PCE) per animal (2000 PCE per specimen) were observed and the frequency of micronucleated polychromatic erythroctyes (MNPCE) (MNPCE/PCE) was calculated.
2) Growth inhibition of bone marrow cells
A total of 500 erythrocytes (TE) per animal (250 TE per specimen) were observed and ratio of PCE to TE (PCE/TE) was calculated.
Evaluation criteria:: All the criteria of the MNPCE/PCE in case of 1-3 or 4 were fulfilled, a test item was considered to be positive:
1) outside the distribution of the historical data of the negative control group
2) the does of the test item exhibits a statistically significant increase compared with the concurrent negative control
3) the increase of the MNPCE/PCE is dose-related
4) both micronucleus test and confirmation test are fulfilled in case of 2) and 3).
Statistics:: MNPCE/PCE: The Conditional Binomial (Kastenbaum and Bowman) was conducted in order to compare the MNPCE/PCE in each dose of the test item group and the positive control group with that of the negative control group. The conditional Binomial test was conducted at upper-tailed significance levels of 5% and 1%. The conditional Binomial test was also conducted for the negative control group with the untreated control group.

PCE/TE: All data except for the positive control were tested by Bartlett's test for homogeneity of variance. Since the variance were homogeneous, Williams' test was performed. Since there were no significant differences, Dunnett's test was performed to compare the mean in the negative control group with each dose of the test item group.
The comparisons between the negative and the positive control group, and the untreated and negative control groups were tested by the F test for homogeneity of variance between the groups. Since the results of the F test showed homogeneity, Student's t-test was performed to compare the mean in the positive control group with that in the negative control group and the mean in the negative control group with that the untreated group. Significance levels of the tests were 5% for the Bartlett's test and the F test, both sides of 5% for Williams' test and both sides of 5% and 1% for the other tests.
Sex:: female
Genotoxicity:: negative
Toxicity:: no effects
Vehicle controls validity:: valid
Negative controls validity:: valid
Positive controls validity:: valid
Sex:: male
Genotoxicity:: negative
Toxicity:: no effects
Vehicle controls validity:: valid
Negative controls validity:: valid
Positive controls validity:: valid
Additional information on results:: The mean of the MNPCE/PCE in the untreated control group was within the range of the negative historical data in the testing facility. The means of MNPCE/PCE in the negative and positive control groups were within the range of the respective historical data in the testing facility. The mean of MNPCE/PCE in the positive control was showed a statistically significant increase at both sides of 1% level compared with the negative control group. In the test item group, the PCE/TE was 20% or more compared with that of the negative control group at all observation doses. Therefore, the results were judged to be negative.
In the PCE/TE, since no statistically significant differences were observed in any doses of the test item group compared to the negative control group, the exposure of the test item to bone marrow was not proved. However, it was considered that the potential to induce micronuclei of the test item could be evaluated adequately, since 2000 mg/kg/day that was the maximum dose in the test method was set in the present test.
Conclusions:: It was concluded that the test item did not induce micronuclei under the present test conditions.

Endpoint conclusion

Endpoint conclusion:: no adverse effect observed (negative)

Additional information

Justification for classification or non-classification

The substance was negative for gene mutation in bacteria and an in vivo study was conducted to investigate the positive result seen the in vitro chromosome aberration study. The results of the in vivo micronucleus study conducted on mice showed that the test substance was negative. Therefore the data available indicates that the substance is not mutagenic and therefore classification under the CLP regulation (EC1272/2008, as amended) is not warranted.

Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.

Test period	From July 26, 2018 to July 30, 2018
With (+) or Without (-) S9 mix	Test item dose (µg/plate)	Number of revertant colonies per plate
		Base-pair substitution						Frameshift
		TA100		TA1535		WP2uvrA		TA98		TA1537
-S9 mix	Negative control	89	(90± 7)	10	(9 ± 2)	20	(24 ± 8)	18	(18 ± 4)	6	(12 ± 6)
		83		7		19		15		12
		97		10		34		22		18
	4.88	91	(96 ± 10)	11	(10 ± 2)	25	(21 ± 4)	14	(17 ± 7)	13	(16 ± 4)
		89		10		18		11		21
		107		8		19		25		15
	19.5	100	(93 ± 6	7	(6 ± 1)	15	(18 ± 5)	20	(17 ± 5)	15	(13 ± 4)
		90		7		15		12		8
		89		5		24		20		15
	78.1	87	(85 ± 6)	10	(8 ± 3)	34	(25 ± 8)	20	(15 ± 6)	14	(13 ± 2)
		90		4		18		8		11
		89		10		22		18		14
	313*	93	(88 ± 13)	3	(4 ± 4)	24	(20 ± 4)	15	(14 ± 1)	17	(12 ± 4)
		98		8		20		13		10
		74		1		17		13		10
	1250*	76	(82 ± 8)	4	(5 ± 1)	10	(14 ± 4)	11	(10 ± 2)	8	(8 ± 1)
		79		6		18		8		7
		91		5		14		11		9
	5000*	77	(77 ± 9)	8	(7 ± 1)	28	(22 ± 6)	8	(11 ± 3)	13	(11 ± 2)
		68		6		16		12		9
		85		6		23		14		11
+S9 mix	Negative control	90	(89 ± 2)	6	(6 ± 2)	21	(26 ± 6)	25	(22 ± 3)	17	(17 ± 5)
		87		4		24		21		12
		91		7		32		20		22
	4.88	90	(95 ± 5)	7	(10 ± 6)	29	(28 ± 4)	22	(30 ± 7)	10	(14 ± 5)
		94		7		24		36		13
		100		17		32		33		19
	19.5	93	(90 ± 25)	10	(11 ± 1)	22	(27 ± 4)	24	( 30 ± 7)	19	(21 ± 4)
		85		11		29		29		25
		85		12		29		38		18
	78.1	119	(89 ± 11)	8	(8 ± 4)	33	(32 ± 4)	26	(28 ± 7)	11	(14 ± 3)
		78		5		27		22		17
		74		12		35		36		13
	313*	83	(89 ± 2)	6	(9 ± 3)	20	(23 ± 3)	32	( 29 ± 7)	13	(15 ± 3)
		83		9		22		21		15
		102		11		26		34		18
	1250*	87	(86 ± 6)	4	(7 ± 4)	21	(22 ± 2)	26	(22 ± 4)	11	(11 ± 1)
		91		5		25		21		11
		89		11		21		19		10
	5000*	89	(86 ± 6)	6	(6 ± 2)	17	(15 ± 2)	24	(23 ± 3)	12	(13 ± 2)
		79		4		14		25		15
		91		7		14		19		13
Positive control -S9 mix	Chemical	AF-2		NaN3		AF-2		AF-2		ICR-191
	Dose ((µg/plate)	0.01		0.5		0.01		0.1		0.5
	No. of revertant colonies/plate	680	(692 ± 12)	492	(492 ± 11)	122	(120 ± 8)	488	(498 ± 9)	474	(482 ± 29)
		703		503		111		504		457
		692		481		127		503		514
Positive control +S9 mix	Chemical	2AA		2AA		2AA		B[a]P		2AA
	Dose ((µg/plate)	1		2		10		5		2
	No. of revertant colonies/plate	897	(896 ± 3)	191	(179 ± 11)	476	(449 ± 56)	318	(302 ± 17)	167	(177 ± 25)
		899		169		485		284		206
		893		177		385		303		159

Test period	From August 10, 2018 to August 13, 2018
With (+) or Without (-) S9 mix	Test item dose (µg/plate)	Number of revertant colonies per plate
		Base-pair substitution						Frameshift
		TA100		TA1535		WP2uvrA		TA98		TA1537
-S9 mix	Negative control	99	(94± 4)	8	(7 ± 1)	39	(44 ± 5)	29	(23 ± 10)	6	(11 ± 6)
		93		6		48		11		11
		91		8		45		28		17
	313*	83	(76 ± 11)	8	(8 ± 3)	32	(35 ± 3)	17	(14 ± 3)	7	(8 ± 3)
		81		5		37		14		6
		63		11		36		11		11
	625*	62	(75 ± 12)	5	(6 ± 3)	37	(29 ± 8)	14	(11 ± 3)	8	(9 ± 3)
		82		9		28		11		12
		82		4		21		8		7
	1250*	71	(77 ± 9)	8	(8 ± 2)	36	(34 ± 2)	8	(12 ± 5)	10	(7 ± 4)
		87		9		32		11		9
		74		6		35		17		3
	2500*	74	(79 ± 4)	6	(5 ± 2)	42	(37 ± 5)	15	(13 ± 2)	4	(4 ± 1)
		80		2		35		13		5
		78		6		33		12		4
	5000*	87	(82 ± 5)	7	(8 ± 3)	42	(38 ± 7)	15	(13 ± 2)	5	(4 ± 1)
		80		12		30		11		4
		78		6		42		14		4
+S9 mix	Negative control	85	(88 ± 9)	7	(14 ± 7)	29	(40 ± 14)	26	(26 ± 6)	10	(13 ± 4)
		80		20		55		21		18
		98		15		35		32		12
	313*	72	(73 ± 5)	5	(6 ± 3)	33	(37 ± 4)	21	(27 ± 6)	15	(18 ± 4)
		78		3		37		27		23
		69		9		41		33		17
	625*	77	(81 ± 3)	14	(8 ± 6)	28	(35 ± 7)	29	(32 ± 6)	14	(13 ± 1)
		83		6		41		38		14
		83		3		38		28		12
	1250*	92	(79 ± 14)	4	(9 ± 5)	32	(34 ± 3)	24	(26 ± 3)	13	(10 ± 3)
		64		14		34		25		7
		80		8		37		30		9
	2500*	60	(76 ± 15)	4	(7 ± 3)	39	(44 ± 5)	15	(20 ± 5)	9	(10 ± 2)
		81		9		48		20		9
		88		9		44		24		13
	5000*	69	(69 ± 4)	5	(7 ± 3)	36	(32 ± 4)	28	(23 ± 4)	8	(9 ± 3)
		73		7		20		22		13
		65		10		31		20		7
Positive control -S9 mix	Chemical	AF-2		NaN3		AF-2		AF-2		ICR-191
	Dose ((µg/plate)	0.01		0.5		0.01		0.1		0.5
	No. of revertant colonies/plate	943	(966 ± 57)	340	(353 ± 19)	141	(125 ± 14)	420	(416 ± 11)	442	(458 ± 16)
		1031		344		121		424		473
		925		374		113		404		459
Positive control +S9 mix	Chemical	2AA		2AA		2AA		B[a]P		2AA
	Dose ((µg/plate)	1		2		10		5		2
	No. of revertant colonies/plate	1230	(1238 ± 14)	210	(187 ± 36)	574	(557 ± 31)	288	(270 ± 26)	162	(157 ± 9)
		1255		146		521		281		147
		1230		206		575		240		162

	-S9 mix					+S9 mix
	TA100	TA1535	WP2uvrA	TA98	TA1537	TA100	TA1535	WP2uvrA	TA98	TA1537
Mean	118	10	33	20	11	109	10	29	27	12
S.D.	18	4	12	6	4	17	3	11	7	4
Upper limit	172	22	69	38	23	160	19	62	48	24
Lower limit	64	1	1	2	1	58	1	1	6	1

	-S9 mix					+S9 mix
	TA100	TA1535	WP2uvrA	TA98	TA1537	TA100	TA1535	WP2uvrA	TA98	TA1537
Chemical	AF-2	NaN3	AF-2	AF-2	ICR-191	2AA	2AA	2AA	B[a]P	2AA
Dose (µg/plate)	0.01	0.5	0.01	0.1	0.5	1	2	10	5	2
Mean	869	282	145	463	604	1476	237	458	264	205
S.D.	89	47	29	56	95	261	35	121	36	38
Upper limit	1136	423	232	631	889	2259	342	821	372	319
Lower limit	602	141	58	295	319	693	132	95	156	91

	-S9 mix					+S9 mix
	TA100	TA1535	WP2uvrA	TA98	TA1537	TA100	TA1535	WP2uvrA	TA98	TA1537
Mean	115	10	31	20	11	107	10	28	27	12
S.D.	18	3	9	6	5	17	3	9	8	8
Upper limit	169	19	58	38	26	158	19	55	51	27
Lower limit	61	1	4	2	1	56	1	1	3	1

Administration group	Dose (mg/kg/day)	Animal no.	Body weight (g)
			The 1^st administration day	The 2^nd administration day	One day after 2^nd administration
			Before administration	Before administration	One day after 2^nd administration
Untreated control	0	101	30.5	31.3	31.5
		102	30.0	30.4	30.5
		103	31.3	31.9	32.2
		104	26.5	26.9	27.2
		105	30.1	30.2	30.7
	Mean±S.D.		29.7 ± 1.85	30.1 ± 1.94	30.4 ± 1.92
Negative control (corn oil)	0	106	29.5	30.1	30.4
		107	29.0	29.5	30.4
		108	31.1	31.3	31.7
		109	28.5	28.7	29.3
		110	29.1	29.5	29.9
	Mean±S.D.		29.4 ± 0.99	29.8 ± 0.97	30.3 ± 0.88
Test item	500	111	29.2	29.2	29.5
		112	29.5	29.3	30.1
		113	31.5	31.6	31.8
		114	28.9	29.8	30.7
		115	30.7	31.1	31.7
	Mean±S.D.		29.9 ± 1.00	30.2 ± 1.09	30.7 ± 1.03
	1000	116	29.7	30.0	30.5
		117	29.2	29.3	29.2
		118	31.2	31.9	32.8
		119	28.3	29.0	29.5
		120	26.9	29.4	29.8
	Mean±S.D.		29.1 ± 1.60	29.9 ± 1.16	30.4 ± 1.45
	2000	121	29.7	30.1	30.1
		122	28.3	28.4	28.5
		123	30.8	30.9	31.6
		124	28.8	28.9	29.4
		125	28.0	27.2	27.8
	Mean±S.D.		29.1 ± 1.14	29.1 ± 1.45	29.5 ± 1.47
Positive control	2	126	30.3	30.9	30.9
		127	27.5	29.1	29.1
		128	29.8	30.6	30.6
		129	28.3	28.6	28.6
		130	30.2	30.7	30.7
	Mean±S.D.		29.2 ± 1.25	29.3 ± 1.23	30.0 ± 1.05

Administration group	Dose (mg/kg/day)	Sampling time after the 2^nd Administration (hours	Animal no.	PCE/TE^a)	MNPCE/PCE^b)
Untreated control	0		101	45.6	0.150
			102	44.0	0.050
			103	40.0	0.125
			104	30.8	0.100
			105	52.8	0.150
		Mean±S.D.		43.6 ± 8.08	0.115 ± 0.0418
		Max/Min.		52.8 / 30.8	0.150 / 0.050
Negative control (corn oil)	0		106	50.2	0.100
			107	54.6	0.125
			108	48.0	0.150
			109	52.0	0.075
			110	49.6	0.200
		Mean±S.D.		50.9 ± 2.52	0.130 ± 0.0481
		Max/Min.		54.6 / 48.0	0.200 / 0.075
Test item	500		111	47.4	0.125
			112	53.4	0.150
			113	44.8	0.075
			114	38.4	0.025
			115	49.2	0.050
		Mean±S.D.		46.6 ± 5.57	0.085 ± 0.0518
		Max/Min.		53.4 / 38.4	0.150 / 0.025
	1000		116	54.8	0.050
			117	43.2	0.000
			118	45.2	0.075
			119	54.0	0.175
			120	59.2	0.125
		Mean±S.D.		51.3 ± 6.80	0.085 ± 0.0675
		Max/Min.		59.2 / 43.2	0.175 / 0.000
	2000		121	66.4	0.125
			122	52.4	0.000
			123	62.4	0.225
			124	44.0	0.050
			125	52.8	0.050
		Mean±S.D.		55.6 ±8.88	0.090 ± 0.0877
		Max/Min.		66.4 / 44.0	0.225 / 0.000
Positive control	2		126	55.0	7.650
			127	53.6	8.325
			128	56.6	6.000
			129	49.0	4.650
			130	47.4	5.700
		Mean±S.D.		52.3 ± 3.95	6.465 ± 1.4966**
		Max/Min.		56.6 / 47.4	8.325 / 4.650

Control	MNPCE/PCE (%, Values in parentheses indicate 95% control limit)
Control	Mean	Lower control limit	Upper control limit
Negative control	0.08	0.02 (0.02)	0.15 (0.14)
Positive control	5.38	3.38 (3.48)	7.38 (7.28)