2-Hydroxypropyl-β-cyclodextrine ethers

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Link to relevant study records

Reference

Endpoint:

fertility, other

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

HPbCD were administered orally before/during mating, and on gestation Day (GD) 0–7, followed by an assessment of embryonic development on GD 14.

GLP compliance:

yes

Specific details on test material used for the study:

Cargill, Cedar Rapids, IA

Species:

rat

Strain:

Crj: CD(SD)

Details on test animals or test system and environmental conditions:

For the rat fertility study, CRL:CDs[SD] female rats aged between 9 and 11 weeks of age at initiation of dosing and weighing between 279 and 355 g (males) and between 203 and 264 g (females) were obtained from Charles River Laboratories (Kingston, NY). Rats were uniquely identified by tattoo and were individually housed in suspended stainless steel wire-bottom cages. Rats were acclimated to laboratory conditions before initiation of dosing. Certified rodent Labdiet 5002 (PMI Nutrition International; Brentwood, MO) and reverse osmosis purified water was provided ad libitum. The room in which the animals were housed was maintained at 72741F, relative humidity 30–70%, and had a 12-h light/dark cycle.

Route of administration:

oral: gavage

Vehicle:

water

Details on exposure:

Control or vehicle articles were administered once daily by oral gavage to females for 2 weeks before and during mating (up to 3 weeks) and on GD 0–7. Since there were no histopathological or organ weight changes in the reproductive organs in a previous 1-month general toxicology repeat dose rat study with these vehicle articles, the control and vehicle articles were administered once daily by oral gavage to males for 3 weeks before mating and during mating (up to 3 weeks) and for 3 weeks after mating.

Details on mating procedure:

During the initial mating phase, one male was housed with one female of the same group for up to 2 weeks. If there was no evidence of mating during this 2-week interval (sperm-positive vaginal smear or observation of a copulatory plug), the female was placed with a proven male from the same dose group for one additional week. Evidence of mating was designated as GD 0, and the male and female mating pair were separated. Therefore, the mating interval was completed within 3 weeks.

Analytical verification of doses or concentrations:

not specified

Dose / conc.:

500 mg/kg bw/day (nominal)

Dose / conc.:

1 000 mg/kg bw/day (nominal)

Control animals:

yes, historical

Oestrous cyclicity (parental animals):

Estrous cyclicity was assessed in all females for 2 weeks before initiation of dosing through the day of mating via vaginal smear, which was taken by lavage. The stages identified were proestrus (round or spindal shaped epithelial cells with granular cytoplasm and few leukocytes), estrus (mostly large cornified epithelial cells without a distinct nucleus), metestrus (cornified epithelial cells, round/spindle shaped epithelial cells and leukocytes), and diestrus (predominantly leukocytes and few epithelial cells). From the smear data, mean estrous cycle length was determined as the number of days from estrus to the next estrus or proestrus to the next proestrus.

Postmortem examinations (parental animals):

All females were euthanized on GD 14 by carbon dioxide (CO2) asphyxiation and the uterus of each female was examined to determine pregnancy status. Corpora lutea were counted and recorded as left and right and the total number per female are presented. Uterine implants were counted and classified as a live fetus, dead fetus, or resorption (early or late), and the total number per animal are presented. A gross examination of the thoracic and abdominal cavities was carried on all F0 females in all dose groups. All males were euthanized within 3 weeks after the completion of the mating phase and a gross examination of the thoracic and abdominal cavities and reproductive organs was carried on all F0 males in all dose groups.

Statistics:

The adult animal or litter was considered as the experimental unit and was evaluated by identifying biologically significant changes and/or using comparative statistical methods. Descriptive statistics are presented as the mean7 standard deviation (SD), unless otherwise noted. Continuous variables including body weight gain, food consumption, number of corpora lutea, and number of implantation sites were analyzed using a one-way analysis of variance (Scheffe, 1959). If these analyses revealed significant differences, pairwise comparisons were performed using Dunnett’s test (Miller, 1981). Noncontinuous variables including % pre-implantation loss, % post-implantation loss, % affected fetuses per litter for total external, visceral and skeletal malformations were analyzed using a Kruskal–Wallis non-parametric analysis of variance (Kruskal and Wallis, 1952). If these analyses revealed significant differences, pairwise comparisons were performed using Dunn’s test (Dunn, 1964). A probability value of Pr0.05 was considered statistically significant.

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not specified

Water consumption and compound intake (if drinking water study):

not specified

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Reproductive function: oestrous cycle:

no effects observed

Reproductive function: sperm measures:

not examined

Reproductive performance:

no effects observed

Key result

Dose descriptor:

NOAEL

Effect level:

>= 1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Remarks on result:

not determinable due to absence of adverse toxic effects

Key result

Critical effects observed:

no

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Remarks on result:

not determinable due to absence of adverse toxic effects

Critical effects observed:

no

Key result

Reproductive effects observed:

no

Conclusions:

Under the conditions of the test HP-beta-CD did not impair the fertility in rats.

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Effect on fertility: via inhalation route

Endpoint conclusion:

no study available

Effect on fertility: via dermal route

Endpoint conclusion:

no study available

Effects on developmental toxicity

Link to relevant study records

Reference

Reference 1

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Principles of method if other than guideline:

Pregnant females were dosed during the period of organogenesis, followed by an assessment of fetal external, visceral,
and skeletal development.

GLP compliance:

yes

Specific details on test material used for the study:

Cargill, Cedar Rapids, IA

Species:

rabbit

Strain:

other: HRA:[NZW]SPF

Details on test animals or test system and environmental conditions:

Timed-mated HRA:[NZW]SPF rabbits aged between 5 and 6 months of age at initiation of dosing and weighing between 2.7 and 3.8 kg were obtained from Covance Research Products (Denver, PA). The female rabbits were mated at the supplier and the day of mating was designated GD 0. Rabbits were uniquely identified by tattoo and ear tag and were individually housed in suspended injection-molded plastic cages. Rabbits were acclimated to laboratory conditions before initiation of dosing. Approximately 140 g of Certified high fiber rabbit diet 5325 (PMI Nutrition International) and 10g of Certified rabbit stix (Bio-Serv, Frenchtown, NJ) was offered daily and reverse osmosis purified water was provided ad libitum. The room in which the animals were housed was maintained at 61–721F, relative humidity 30–70%, and had a 12-h light/dark cycle. The use of animals in this study followed the guide- lines provided in the NRC Guide for the Care and Use of Laboratory Animals (1996) and the Animal Welfare Act. This study was approved by the facility’s Institutional Animal Care and Use Committee and was conducted in an Association for the Assessment and Accreditation of Laboratory Animal Care accredited facility.

Route of administration:

oral: gavage

Details on exposure:

Control or vehicle articles were administered once daily by oral gavage on GD 7–19 (N520 animals/group).

Analytical verification of doses or concentrations:

not specified

Dose / conc.:

500 mg/kg bw/day (nominal)

Dose / conc.:

1 000 mg/kg bw/day (nominal)

No. of animals per sex per dose:

20/group

Control animals:

yes, historical

Maternal examinations:

Maternal body weights were recorded on GD 0, 7, 10, 13, 16, 19, 22, 25, and 29. Food consumption was visually estimated such that a value of 0 indicated that the rabbit ate 0–19% of food offered; a value of 1 indicated that the rabbit ate 20–79% of food offered; a value of 2 indicated that the rabbit ate 80–100% of food offered. Food consumption was visually estimated daily from 2 days after arrival (GD 1 to 5) through GD 29. All females were observed once daily for physical signs of toxicity on the day of arrival through the day of necropsy on GD 29. During the dosing interval (GD 7–19), females were also observed 1–3 h after dosing. Females were euthanized on GD 29 by an intravenous injection of Beuthanasia-D-Special (Schering-Plough) and the uterus of each female was examined to determine pregnancy status. Corpora lutea were counted and recorded as left and right and the total number per female are presented. A gross examination of the thoracic and abdominal cavities was performed on all F0 females in all dose groups.

Ovaries and uterine content:

Uterine implants were counted and each was classified as a live fetus, dead fetus, or resorption (early or late), and the total number per animal are presented. Placental morphology was evaluated by gross evaluation.

Fetal examinations:

All fetuses were weighed and examined externally. After external examination, each fetus was euthanized by intraperitoneal injection of Beuthanasia-D-Special (Schering- Plough). The heads of all fetuses were examined after fresh, free-hand coronal sectioning, and a fresh visceral examination was performed on all fetuses using a modified Staples’ technique (Stuckhardt and Poppe, 1984). The gender of each fetus was determined by visceral examination of the gonads. All fetuses were subsequently fixed in 95% ethanol and stained with alizarin red for skeletal examination. Fetal observations were recorded in general accordance with internationally developed terminology (Wise et al., 1997).

Statistics:

The adult animal or litter was considered as the experimental unit and was evaluated by identifying biologically significant changes and/or using comparative statistical methods. Descriptive statistics are presented as the mean7 standard deviation (SD), unless otherwise noted. Continuous variables including body weight gain, food consumption, number of corpora lutea, and number of implantation sites were analyzed using a one-way analysis of variance (Scheffe, 1959). If these analyses revealed significant differences, pairwise comparisons were performed using Dunnett’s test (Miller, 1981). Noncontinuous variables including % pre-implantation loss, % post-implantation loss, % affected fetuses per litter for total external, visceral and skeletal malformations were analyzed using a Kruskal–Wallis non-parametric analysis of variance (Kruskal and Wallis, 1952). If these analyses revealed significant differences, pairwise comparisons were performed using Dunn’s test (Dunn, 1964). A probability value of Pr0.05 was considered statistically significant.

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

In the rabbit teratology study, both the 500 and 1,000 mg/kg HPbCD groups exhibited stool findings (loose and/or scant stool) and concomitant effects on food consumption and body weight, when compared with MC. Owing to this excessive maternal toxicity, four rabbits in the 500 mg/kg and three rabbits in the 1,000 mg/kg HPbCD groups were euthanized for humane reasons on GD 16–20. In addition to these mortalities described above, one additional rabbit each in the 500 and 1,000 mg/kg HPbCD groups was euthanized because of abortion, which was attributed to maternal toxicity (scant stool, decreased food consumption, and body weight loss).

Mortality:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Individual rabbits in the 500 and 1,000 mg/kg HPbCD groups exhibited decreases in body weight gain during GD 7–19, when compared with MC (data not shown). This finding correlated with decreased food consumption and stool findings. During the post-dosing interval, mean body weights and food consumption in these HPbCD groups exhibited evidence of recovery and were comparable to the MC group.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not specified

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

effects observed, non-treatment-related

Description (incidence and severity):

In the rabbit teratology study, two rabbits in the 1,000mg/kg HPbCD group exhibited enlarged gallbladders (data not shown), and one of these two rabbits had aborted.

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Number of abortions:

effects observed, treatment-related

Description (incidence and severity):

Due to maternal toxicity as described above.

Pre- and post-implantation loss:

no effects observed

Total litter losses by resorption:

no effects observed

Early or late resorptions:

no effects observed

Dead fetuses:

no effects observed

Changes in pregnancy duration:

no effects observed

Changes in number of pregnant:

no effects observed

Key result

Dose descriptor:

NOAEL

Effect level:

< 500 mg/kg bw/day (nominal)

Based on:

test mat.

Basis for effect level:

body weight and weight gain

clinical signs

food consumption and compound intake

other: effects on the digestive tract

Remarks on result:

not determinable due to adverse toxic effects at highest dose / concentration tested

Key result

Abnormalities:

no effects observed

Fetal body weight changes:

no effects observed

Reduction in number of live offspring:

no effects observed

Changes in sex ratio:

no effects observed

Changes in litter size and weights:

no effects observed

Changes in postnatal survival:

no effects observed

External malformations:

no effects observed

Skeletal malformations:

no effects observed

Visceral malformations:

no effects observed

Key result

Dose descriptor:

NOAEL

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Remarks on result:

not determinable due to adverse toxic effects at highest dose / concentration tested

Key result

Abnormalities:

no effects observed

Key result

Developmental effects observed:

no

Conclusions:

Under the conditions of the test HP-beta-CD did not show embryonal toxicity or teratogenic effects in rats.

Reference 2

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Principles of method if other than guideline:

Pregnant females were dosed during the period of organogenesis, followed by an assessment of fetal external, visceral,
and skeletal development.

GLP compliance:

yes

Specific details on test material used for the study:

Cargill, Cedar Rapids, IA

Species:

rat

Strain:

Crj: CD(SD)

Details on test animals or test system and environmental conditions:

Timed-mated CRL:CDs[SD] female rats that were 11 weeks of age at initiation of dosing and weighing between 227 and 300g were obtained from Charles River Laboratories (Kingston, NY). The female rats were mated overnight, and the day on which a sperm plug was observed was determined as GD 0 for that female. Rats were uniquely identified by tattoo and were individually housed in suspended stainless steel wire-bottom cages. Rats were acclimated to laboratory conditions before initiation of dosing. Certified rodent Labdiet 5002 (PMI Nutrition Interna- tional) and reverse osmosis purified water was provided ad libitum. The room in which the animals were housed was maintained at 72741F, relative humidity 30–70%, and had a 12-h light/dark cycle.

Route of administration:

oral: gavage

Details on exposure:

Control or vehicle articles were administered once daily by oral gavage on GD 6–17 (N522 animals/group). Maternal body weights were recorded on GD 0, 6, 9, 12, 15, 17, and 21. Food consumption was recorded for the following intervals: GD 0–6, 6–12, 12–17, and 17–21. All females were observed once daily for physical signs of toxicity on GD 0 and on GD 5 through the day of necropsy on GD 21. During the dosing interval (GD 6–17), females were also observed 1–3 h after dosing.

Dose / conc.:

500 mg/kg bw/day (nominal)

Dose / conc.:

1 000 mg/kg bw/day (nominal)

No. of animals per sex per dose:

20/group

Control animals:

yes, historical

Maternal examinations:

All females were euthanized on GD 21 by CO2 asphyxiation and the uterus of each female was examined to determine pregnancy status.

Ovaries and uterine content:

Corpora lutea were counted and recorded as left and right and the total number per female are presented. Uterine implants were counted and each was classified as a live fetus, dead fetus, or resorption (early or late), and the total number per animal are presented. Placental morphology was evaluated by gross evaluation. A gross examination of the thoracic and abdominal cavities was performed on all F0 females in all dose groups.

Fetal examinations:

All fetuses were weighed, sexed, and examined externally. After external examination, each fetus was euthanized by intraperitoneal injection of Beuthanasia-DSpecial (Schering-Plough, Union, NJ). Approximately 50% of fetuses in each litter were subjected to fresh visceral examination, using a modified Staples’ technique (Stuckhardt and Poppe, 1984), with the fetal head fixed in Bouins’ solution and subsequently examined by free-hand coronal sectioning using Wilson’s technique (Wilson and Warkany, 1965). The remaining 50% of fetuses were fixed in 95% ethanol and stained with alizarin red for skeletal examination. Fetal observations were recorded in general accordance with internationally developed terminology (Wise et al., 1997). Fetal external, visceral, and skeletal observations were classified as malformations or variations based on standard definitions (Chahoud et al., 1999; Paumgartten et al., 2009).

Statistics:

The adult animal or litter was considered as the experimental unit and was evaluated by identifying biologically significant changes and/or using comparative statistical methods. Descriptive statistics are presented as the mean7 standard deviation (SD), unless otherwise noted. Continuous variables including body weight gain, food consumption, number of corpora lutea, and number of implantation sites were analyzed using a one-way analysis of variance (Scheffe, 1959). If these analyses revealed significant differences, pairwise comparisons were performed using Dunnett’s test (Miller, 1981). Noncontinuous variables including % pre-implantation loss, % post-implantation loss, % affected fetuses per litter for total external, visceral and skeletal malformations were analyzed using a Kruskal–Wallis non-parametric analysis of variance (Kruskal and Wallis, 1952). If these analyses revealed significant differences, pairwise comparisons were performed using Dunn’s test (Dunn, 1964). A probability value of Pr0.05 was considered statistically significant.

Clinical signs:

no effects observed

Mortality:

no mortality observed

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not specified

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Neuropathological findings:

not specified

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Number of abortions:

no effects observed

Pre- and post-implantation loss:

no effects observed

Total litter losses by resorption:

no effects observed

Early or late resorptions:

no effects observed

Dead fetuses:

no effects observed

Changes in pregnancy duration:

no effects observed

Changes in number of pregnant:

no effects observed

Key result

Dose descriptor:

NOAEL

Effect level:

>= 1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Remarks on result:

not determinable due to absence of adverse toxic effects

Key result

Abnormalities:

no effects observed

Fetal body weight changes:

no effects observed

Reduction in number of live offspring:

no effects observed

Changes in sex ratio:

no effects observed

Changes in litter size and weights:

no effects observed

Changes in postnatal survival:

not examined

External malformations:

no effects observed

Skeletal malformations:

no effects observed

Visceral malformations:

effects observed, non-treatment-related

Description (incidence and severity):

There was a low incidence of small or enlarged spleen in the 1,000 mg/kg HPbCD group when compared with MC. However, the presence of these findings at a low incidence in all vehicle groups suggests that it is a spurious finding and not related to the vehicle articles. Furthermore, large spleen and small spleen have been observed in control fetuses at other laboratories (Charles River, 2009). Other visceral and skeletal examination findings included convoluted ureter, supernumerary blood vessels, and reduced ossification of the maxilla bone, respectively. However, these are relatively common findings in this species of laboratory rat fetuses and the incidence was similar to those previously observed in control rats in this laboratory.

Key result

Dose descriptor:

NOAEL

Effect level:

>= 1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Remarks on result:

not determinable due to absence of adverse toxic effects

Key result

Abnormalities:

effects observed, non-treatment-related

Localisation:

other: spleen

Description (incidence and severity):

There was a low incidence of small or enlarged spleen in the 1,000 mg/kg HPbCD group when compared with MC. However, the presence of these findings at a low incidence in all vehicle groups suggests that it is a spurious finding and not related to the vehicle articles. Furthermore, large spleen and small spleen have been observed in control fetuses at other laboratories (Charles River, 2009). Other visceral and skeletal examination findings included convoluted ureter, supernumerary blood vessels, and reduced ossification of the maxilla bone, respectively. However, these are relatively common findings in this species of laboratory rat fetuses and the incidence was similar to those previously observed in control rats in this laboratory.

Key result

Developmental effects observed:

yes

Lowest effective dose / conc.:

1 000 mg/kg bw/day (nominal)

Treatment related:

no

Relation to maternal toxicity:

developmental effects in the absence of maternal toxicity effects

Conclusions:

Under the conditions of the test HP-beta-CD did not show embryonal toxicity or teratogenic effects in rats.

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no adverse effect observed

Effect on developmental toxicity: via inhalation route

Endpoint conclusion:

no study available

Effect on developmental toxicity: via dermal route

Endpoint conclusion:

no study available