TABLE 13.
Incidence of fetuses/litters with malformations in the rat after maternal oral administration of DDAC
| Fetal malformations | DDAC dose level (mg/kg/day) | |||
|---|---|---|---|---|
| 0 (control) | 1 | 10 | 20 | |
| Number examined externally | 337/25a | 337/24 | 319/24 | 311/23 |
| Thread‐like tail and imperforate anus | 1/1b | 0/0 | 0/0 | 0/0 |
| Umbilical hernia | 0/0 | 0/0 | 0/0 | 1/1 |
| Micrognathia | 0/0 | 0/0 | 0/0 | 1/1c |
| Fetus edematous | 0/0 | 0/0 | 1/1 | 0/0 |
| Shortened hindpaw | 1/1d | 0/0 | 0/0 | 0/0 |
| Number examined viscerally | 176/25 | 175/24 | 164/24 | 162/23 |
| Hydroureter and/or hydronephrosis | 3/3 | 6/4 | 14/7 | 6/5 |
| Number examined skeletally | 161/25 | 162/24 | 155/24 | 149/23 |
| Ribs, centra, and arches absent (cervical, thoracic, lumber, and sacral) | 1/1b | 0/0 | 0/0 | 0/0 |
| One cervical or lumbar arch and/or centrum absent | 1/1 | 0/0 | 0/0 | 1/1 |
| Rib #13 absent—unilateral | 0/0 | 0/0 | 2/2 | 0/0 |
| Total number with malformations | 6/5 | 6/4 | 16/9 | 9/6 |
Abbreviation: DDAC, didecyl dimethyl ammonium chloride.
a
Data are presented as number of fetuses/number of litters.
b
The same fetus exhibited the external and skeletal malformations.
c
The eye bulge was also absent during external examination and a skeletal examination of this fetus revealed that the nasal, premaxillary, and mandible bones were malformed.
d
The skeletal examination of this fetus revealed that the proximal and distal phalanges of the hindpaw were absent.