3-chloropropene

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1979-02-13 to 1980-08-13

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: - scientifically sound study - generally guideline compliant, but only 2 dose groups, doses spaced by a factor of 10 - GLP compliant

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Teratologic evaluation of inhaled epichlorohydrin and allyl chloride in rats and rabbits.

Author:

John JA, Gushow TS, Ayres JA, Hanley TR Jr, Quast JF, Rao KS.

Year:

1983

Bibliographic source:

Fundam Appl Toxicol. 1983 Sep-Oct;3(5):437-42.

Reference 2

Reference Type:

study report

Title:

Unnamed

Year:

1980

Report date:

1980

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Deviations:

yes

Remarks:

: only two doses, spaced by a factor of 10

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Automatically generated during migration to IUCLID 6, no data available

IUPAC Name:

Automatically generated during migration to IUCLID 6, no data available

Details on test material:

- Name of test material (as cited in study report): Allyl chloride
- Physical state:
- Analytical purity: 98.60%
- Impurities (identity and concentrations):
Isopropyl chloride 0.74%
1,5-hexadiene 0.40%
N-propyl chloride 0.14%
2,2-Dichloropropane 0.10%
Specific gravity 0.934
Distillation Range
Initial Boiling Point 43°C
Dry Point 49°C
- Purity test date: not reported
- Lot/batch No.: Lot No. TB 06308-3
- Provider: Dow Chemical Company, Freeport, Texas, U.S.A.
- Expiration date of the lot/batch: not reported
- Stability under test conditions: not reported, but expected to be stable
- Storage condition of test material: not reported

Test animals

Species:

rat

Strain:

Sprague-Dawley

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Spartan Research Animals, Haslett, Michigan
- Age at study initiation: not reported, delivered timed pregnant (d 3 of gestation)
- Weight at study initiation: 300 g
- Fasting period before study: not reported
- Housing: group-housed during exposures, singly during the rest of the time in wire mesh cages
- Diet (e.g. ad libitum): laboratory animal chow (Ralston Purina Company, St. Louis, Missouri, U.S.A.)
- Water (e.g. ad libitum): tap water ad libitum
- Acclimation period: no


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22.2
- Humidity (%): 45%
- Air changes (per hr): NOT REPORTED
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure (if applicable):

whole body

Vehicle:

unchanged (no vehicle)

Details on exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: 4.3 cubic meter stainless steel and glass Rochester-type inhalation chambers
- Method of holding animals in test chamber: group housed in wired mesh cages
- Source and rate of air: not reported
- Method of conditioning air: control system to maintainrelative humidity at approximately 40-60%, recorded daily
- System of generating vapor: pumping allyl chloride at calculated rates into a J-shaped glass tube where it vaporized due to incoming warm air. Vapors from the J-tube were swept into the chamber air supply duct with compressed air and mixed with oncoming air by turbulence while maintaining total chamber airflow at 800-900 liters per minute (12 air changes per hour).
- Temperature, humidity, pressure in air chamber: temperature: 21.1 - 23-9 °C, humidity: 40 - 60 %, pressure slightly negative
- Air flow rate: 800-900 liters per minute
- Air change rate: 12
- Treatment of exhaust air: not reported


TEST ATMOSPHERE
- Brief description of analytical method used: IR
- Samples taken from breathing zone: not reported in detail, but distribution within the chambers was determined to be uniform within 10% of the target concentrations prior to initiating exposures


VEHICLE (if applicable)
- no vehicle used

Details on analytical verification of doses or concentrations:

- concentration measured 2-3 times per hour (14-21 times daily) by infrared spectrophotometry (Miran I Infrared Analyzer at a wavelength of 10.6 µm)

Details on mating procedure:

- Impregnation procedure:purchased timed pregnant
- Proof of pregnancy: sperm in vaginal smear, referred to as day 0 of pregnancy

Duration of treatment / exposure:

7 h/d, d 6 - d 15 of gestation

Frequency of treatment:

daily

Duration of test:

d 6 - d 21 of gestation

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
0, 30, 300 ppm (= 0, 93, 930 mg/m³)
Basis:
nominal conc.

Doses / concentrations 2

Remarks:

Doses / Concentrations:
0, 30 ± 2 and 297 ± 6 ppm
Basis:
analytical conc.

No. of animals per sex per dose:

25 - 39 female rats

Control animals:

yes, sham-exposed

Details on study design:

- Dose selection rationale: based on a range finding study (see overall remarks on methods)
- Rationale for animal assignment (if not random): random, computer generated random numbers

Examinations

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily


DETAILED CLINICAL OBSERVATIONS: No


BODY WEIGHT: Yes
- Time schedule for examinations: d 6, 8, 10, 12, 16


FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Yes, at 3 d intervalls, starting on d 6


WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): Yes, at 3 d intervalls, starting on d 6


POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day # 21
- Organs examined: weighing: liver, kidneys; preserved for potential histology: kidney, heart, liver, nasal turbinates, trachea, lungs

Ovaries and uterine content:

- Sacrifice via carbon dioxide inhalation
The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: No, but fetuses weighted
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of resorptions: Yes
- resorptions were not distinguished into late and early, only in non-pregnant animals were stained with a 10% solution of sodium sulfide (Kopf et al., 1964) and examined for evidence of early resorption sites.

Fetal examinations:

- External examinations: Yes, all
- Soft tissue examinations: Yes: one third per litter, selected by a table of random numbers, by dissection under a low power microscope for evidence of soft-tissue alterations (Staples, 1974).
- Skeletal examinations: Yes: all per litter
- Head examinations: Yes: one third per litter, identical to the animals used for soft tissue examinations

Statistics:

- frequency of alterations and resorptions among litters and the fetal population: Wilcoxon test as modified by Haseman and Hoel (1974)
- percentage of pregnancy, maternal survival, and of other incidence data: Fischer's exact probability test (Siegel, 1956)
- body weights and the body measurements, maternal weight gain, and maternal organ weights: ANOVA
- group means: Dunnett's test (Steel and Torrie, 1960)
- fetal sex ratio: binomial distribution test (Steel and Torrie, 1960).
-

Indices:

% of pregnancy
Number of litters
Corpora lutea/dam
Implantation sites/dam
Pre-implantation loss
Fetuses/littere
Resorptions/litter
% Implantations resorbedg
% Litters with resorptions
Litters toltally resorbed
Resorptions/litters with resorptions
% Dead fetuses
sex ration
fetal body weight
fetal crown rump length

Historical control data:

not reported in detail

Results and discussion

Results: maternal animals

Maternal developmental toxicity

Details on maternal toxic effects:

Maternal toxic effects:no effects

Details on maternal toxic effects:
In the high dose group slightly significantly raised absolute liver and kidney weights were found while only a trend for raised the relative liver and kidney weights was seen (statistical significance was not reached). In addition in the first 3 d of treatment the bodyweight of dams of the high dose group were reduced, but this was compensated subsequently by a higher body weight gain during the rest of the treatment period.

Effect levels (maternal animals)

1

Dose descriptor:

NOAEC

Effect level:

30 ppm (analytical)

Basis for effect level:

other: maternal toxicity

2

Dose descriptor:

LOAEC

Effect level:

300 ppm (analytical)

Basis for effect level:

other: maternal toxicity

Results (fetuses)

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:yes

Details on embryotoxic / teratogenic effects:
- No adverse effects were seen in the indices describing the efficiency of pregnancy.
- A statistically significant rise in the occurence of unossified sternebrae and delayed ossification of vertebral centra was found in the high dose group.
- External or soft tissue alteration seen were incidential and not statistically or biologically significantly different from the controls or from historical ontrol data:
at 300 ppm: One fetus exhibited a caudia and imperforate anus and a litter-mate exhibited hypoplastic tail . Short trunk and ectopicovaries were noted in both of these fetuses . One additional fetus exhibited an alteration in which the innominate artery was not formed but the right carotid and subclavian arteries branched directly off the aorta .
controls: Two control fetuses exhibited omphalocele. These malformations have been observed at low incidences in historical control litters from Sprague-Dawley rats tested in this laboratory.

Effect levels (fetuses)

1

Dose descriptor:

NOAEC

Effect level:

30 ppm (analytical)

Basis for effect level:

other: teratogenicity

2

Dose descriptor:

LOAEC

Effect level:

300 ppm (analytical)

Basis for effect level:

other: teratogenicity

Fetal abnormalities

Abnormalities:

not specified

Overall developmental toxicity

Developmental effects observed:

not specified

Any other information on results incl. tables

- Table 1: Body Weights and Organ Weights of Rats Exposed to 3 -Chloropropene

	ppm 3-chloropropene
	0	30	300
Number of dams b	34	24	22
Body weight on gestation day
6	290 ± 20c	294 ± 20	296 ± 18
8	296 ± 19	300 ± 20	292 ± 17
10	303 ± 20	312 ± 21	305 ± 19
12	317 ± 21	325 ± 19	317 ± 21
16	345 ± 25	358 ± 26	350 ± 24
21	429 ± 40	436 ± 44	444 ± 41
Maternal liver weight on gestation day 21
absolute e	15.97±1.50	17.15±2.37 d	17.70±1.76 d
relative f	38.02±3.93	39.37±3.95	39.92±2.66
Maternal kidney weight on gestation day 21
absolute e	1.92±0.18	2.02±0.27	2.15±0.14 d
relative g	4.53±0.67	4.67±0.78	4.88±0.41

a: Rats were exposed to 0, 30, or 300 ppm of allyl chloride for 7 hrs/day on days 6 through 15 of gestation.

b: Data from non-pregnant rats were not included in these analyses.

c: Mean ± S.D.

d: Significantly different from the control value by Dunnett's Test, p<0.05.

e: g, mean ± S.D.

f: g liver/kg body weight, mean ± S.D.

g: g kidney/kg body weight, mean ± S.D.

- Table 2: Observations Made at the Time of Cesarean Section of Rats Exposed to 3 -chloropropene by Inhalation a

	ppm 3-cchloropropene
	0	30	300
Number of bred females	39	25	25
Number of deaths/no. of females bred	0/39	0/25	0/25
% pregnant b	87(34/39)	96(24/25)	88(22/25)
Pregnancies detected by stain c	0	0	0
% pregnant, tota1d	87(34/39)	96(24/25)	88(22/25)
Number of litters	34	24	22
Corpora lutea/dam e	14 ± 2	14 ± 2	14 ± 2
Implantation sites/dam e	13 ± 3	13 ± 3	13 ± 3
Pre-implantation loss f	9.1 ± 16.4	5.8 ± 8.4	9.3 ± 13.1
Petuses/litter e	12 ± 3	12 ± 4	12 ± 3
Resorptions/litter e	0.9 ± 1.8	1.3 ± 2.6	0.8 ± 0.9
% Implantations resorbed g	7(31/446)	10(31/312)	6(17/286)
% litters wit resorptions g	50(17/34)	50(12/24)	50(11/22)
Litters totally resorbed g	1	1	0
Resorptions/litters with resorptions g	1.8(31/17)	2.6(31/12)	1.6(17/11)
% Dead fetuses	0(0/415)	0(0/281)	0(0/269)
Sex ratio, M:F	51:49	51:49	50:50
Fetal body weight (g) h	5.63±0.21	5.59 ± 0.32	5.55 ± 0.27
Fetal crown-rump length (mm) h	45.1 ± 1.1	45.0 ± 1.9	44.7 ± 1.5

a: Rats were exposed to 0, 30, or 300 ppm of allyl chloride for 7 hr/day on days 6 through 15 of gestation.

b:No. of females with visible implantation sites at the time of cesarean section /total no. of bred females.

c: No. of females with implantation sites detected only after staining the uterus with sodium sulfide stain.

d: No. of females with implantation sites as observed either visually at the time of cesarean section or after staining the uterus with sodium sulfide stain/total no. of bred females.

e: Mean t S.D.

(Percent per litter, mean*S.D.

g: Resorptions which were detected only by sodium sulfide staining were not included in these calculations.

h: Mean of litter means*S.D.

No values were significantly different from the control value by the appropriate statistical test, <0.05.

- Table 3: Incidence of Fetal Alterations Among Litters of Rats Exposed to 3 -Chloropropene by Inhalations

External Examination Soft-Tissue Examination Skeletal Examination Bones Of The Skull		ppm 3 -Chloropropene
		0	30	300
		Number Fetuses (Number Litters) Examined
		415(33) 141(33) 415(33) 274(32)b	281(23) 96(23) 281(23) 185(22)b	269(22) 93(22) 269(22) 176(22)
		Percent affected (Number affected)
Total Major Malformations	Fc	1(2)	0	2(4)
	L	6(2)	0	14(3)
External Alterations
Short trunk*	F	0	0	1(2)d
	L	0	0	5(1)
Hypoplastic Tail*	F	0	0	0.4(1)d
	L	0	0	5(1)
Acaudia and imperforate	F	0	0	0.4(1)d
anus*	L	0	0	5(1)
Omphalocele*	F	1(2)	0	0
	L	6(2)	0	0
Soft-Tissue Alterations
Innominate artery unformed. Right vessels branch directly from aorta*	F	0	0	1(1)
	L	0	0	5(1)
Dilated ureter	F	1(1)	1(1)	1(1)
	L	3(1)	4(1)	5(1)
Dilated renal pelvis	F	0	0	1(1)
	L	0	0	5(1)
Slightly dilated ventricles	F	0	1(1)	1(1)
of the brain	L	0	4(1)	5(1)
Pale and hemorrhagic liver	F	0	0	1(1)
	L	0	0	5(1)
Pale and undersized kidney	F	0	0	1(1)
and spleen	L	0	0	5(1)
Pinpoint hemorrhage -	F	0	0	1(1)
kidneys	L	0	0	5(1)
Ectopic ovaries*	F	0	0
	L	0	0	5(1)
Satellite vessel	F	1(1)	0	0
	L	3(1)	0	0
Cerebral hemorrhage	F	0	0	1(1)
	L	0	0	5(1)
Skull-delayed ossification	F	8(21)	12(22)	6(11)
	L	44(14)	50(11)	23(5)
--extra site of ossification	F	2(6)	1(2)	1(2)
	L	13(4)	5(1)	9(2)
--bone island	F	0.4(1)	0	1(1)
	L	3(1)	0	5(1)
Sternebrae-delayed	F	5(21)	7(19)	11(29)e
ossification	L	39(13)	52(12)	55(12)
--unfused	F	0	0	1(3)
	L	0	0	14(3)
--unossified sternebrae	F	0	0	3(9)f
	L	0	0	18(4)
Ribs-extra rib(s)	F	1(4)	0.4(1)	0.4(1)
	L	6(2)	4(1)	5(1)
--lumbar spur(s)	F	15(60)	16(44)	6(17)f
	L	70(23)	78(18)	36(8)
--wavy	F	0	0.4(1)	0.4(1)
	L	0	4(1)	5(1)
--extra pair of ribs, vertebrae and centra	F	0	0	0.4(1)
	L	0	0	5(1)
--pair of ribs, thoracic, vertebrae and centra missing*	F	0	0	1(3)
	L	0	0	9(2)
Vertebrae-delayed, ossification, cervical centra	F	25(103)	24(67)	40(107)1
	L	82(27)	83(19)	91(20)
--unfused thoracic centra	F	1(2)	1(2)	0.4(,1)
	L	6(2)	9(2)	5(1)
--bilobed thoracic centra	F	5(20)	5(15)	3(8)
	L	49(16)	35(8)	32(7)
--delayed ossification	F	0	0	0.4(1)
thoracic centre	L	0	0	5(1)
--missing thoracic,	F	0	0	1(2)
lumbar and sacral vertebrae, centra and ribs*	L	0	0	5(1)

*: considered to be a major malformation.

a: Rats were exposed to 0, 30, or 300 ppm of aryl chloride for 7 hr/day on days 6 through 15 of gestation.

b: Due to the small number of fetuses in these litters, one litter of rats at the control and 30 ppm dose levels were not examined for bones of the skull. The heads of all fetuses in these litters were removed during the examination for soft tissue alterations.

c: F = fetuses, L = litters

d: One litter at the 300 ppm dose level contained 2 fetuses exhibiting short trunk. Hypoplastic tail was noted in one fetus and acaudia and imperforate anus was

observed in the second fetus. Both fetuses exhibited ectopic ovaries and were missing thoracic, lumbar and sacral vertebrae, vertebral centra and ribs.

e: p=0.0503, modified Wilcoxon test.

f: Significantly different from the control values by a modified Wilcoxon Test, p<0.05.

Applicant's summary and conclusion

Conclusions:

A teratogenicity study was conducted in rats generally equivalent to OECD TG 414. Female rats were exposed to 0,30 and 300 ppm 3-chloropropene for 7 h/d, daily from d 6 to d 15 of gestation.
Very slight maternal toxicity was seen at 300 ppm, accompanied by a statistically significant rise in the occurrence of unossified sternebrae and delayed ossification of vertebral centra in the offspring of this dose group.
In neither dose group adverse effects were seen in the indices describing the efficiency of pregnancy.
The NOAEC for maternal toxicity and fetotoxicity/teratogenicity is 30 ppm.

Executive summary:

In the present study (Deacon 1980) pregnant female Sprague Dawley rats were exposed to 3 -chloropropene vapors of 0, 30 and 300 ppm for 7 h/d, daily from d 6 to d 15 of gestation following generally OECD TG 414.

A NOAEC of 30 ppm (93 mg/m³) for maternal toxicity and fetotoxicity/teratogenicit and a corresponding LOAEC of 300 ppm (930 mg/m³) can be derived.

Pregnant Spague-Dawley rats were exposed to 3 -chloropropene (whole body). At day 20 they were sacrificed and a full teratology examination was performed (analysis of maternal reproductive organs and external and soft tissue analysis of litters). The treatment resulted in a slight maternal toxicity as shown by slightly significantly raised absolute liver and kidney weights in the high dose group (300 ppm) while only a trend for raised the relative liver and kidney weights was seen (statistical significance was not reached). In addition in the first 3 d of treatment the bodyweight of dams of the high dose group were reduced, but this was compensated subsequently by a higher body weight gain during the rest of the treatment period.

No adverse effects were seen in the indices describing the efficiency of pregnancy in any of the treatment groups. A statistically significant rise in the occurrence of unossified sternebrae and delayed ossification of vertebral centra was found in the high dose group (300 ppm). External or soft tissue alteration seen were incidental and not statistically or biologically significantly different from the controls or from historical control data.