Dioctyl phosphonate

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Description of key information

NOAEL reproductive toxicity = 800 mg/ kg bw/ day

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

800 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

Study conducted according to internationally accepted testing guidelines.

Effect on fertility: via inhalation route

Endpoint conclusion:

no study available

Effect on fertility: via dermal route

Endpoint conclusion:

no study available

Additional information

A Combined Repeated Dose Toxicity Study with the Reproduction/Developmental Toxicity Screening Test according to OECD TG 422 was performed on Dioctyl phosphonate . The test item was administered by oral gavage to Sprague Dawley rats (10 males and 10 females for each main group) using corn oil for vehicle at dose levels of 0, 100, 300 e 800 mg/kg bw/day. The assessment of delayed toxicity or persistence of adverse effects was performed on recovery groups (5 males and 5 females for each dose group) . Males of the main groups were treated for 2 weeks prior to pairing and during pairing with females until the day before necropsy, for a total of 31 days. Females were treated for 2 weeks prior to pairing, and thereafter during pairing, post coitum and postpartum periods until Day 13 post partum (for at least 51 days). Recovery animals (males) were treated for up to 4 consecutive weeks and killed after 4 weeks of recovery period. Recovery animals (females) were treated for up to 6 weeks and killed after 4 weeks of recovery period. No relevant differences were found in terms of mating performance including the pre-coital interval (number of days paired to sperm positive day), copulatory evidence (the positive identification of mating i.e. the presence of sperm and/or copulation plug in situ or in the cage) or fertility index both for main groups and for recovery groups respect to control group. All pregnant females had a comparable length of gestation period and gave birth between day 21 and 23 post coitum. Based on the results of this study, the NOAEL (No Observed Adverse Effect Level) for reproductive toxicity was considered to be 800 mg/kg bw/day for both males and females.

Effects on developmental toxicity

Description of key information

NOAEL developmental toxicity = 800 mg/ kg bw/ day

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

800 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

Study conducted according to internationally accepted testing guidelines.

Effect on developmental toxicity: via inhalation route

Endpoint conclusion:

no study available

Effect on developmental toxicity: via dermal route

Endpoint conclusion:

no study available

Additional information

A Combined Repeated Dose Toxicity Study with the Reproduction/Developmental Toxicity Screening Test according to OECD TG 422 was performed on Dioctyl phosphonate. The test item was administered by oral gavage to Sprague Dawley rats (10 males and 10 females for each main group) using corn oil for vehicle at dose levels of 0, 100, 300 e 800 mg/kg bw/day. The assessment of delayed toxicity or persistence of adverse effects was performed on recovery groups (5 males and 5 females for each dose group) . Males of the main groups were treated for 2 weeks prior to pairing and during pairing with females until the day before necropsy, for a total of 31 days. Females were treated for 2 weeks prior to pairing, and thereafter during pairing, post coitum and postpartum periods until Day 13 post partum (for at least 51 days). Recovery animals (males) were treated for up to 4 consecutive weeks and killed after 4 weeks of recovery period. Recovery animals (females) were treated for up to 6 weeks and killed after 4 weeks of recovery period. Litter data and sex ratios were unaffected by treatment. Similar clinical signs were recorded in control and treated pups during the lactation period. No relevant differences were seen between the control and treated pups in anogenital distance and no nipple was observed in males pups neither on 13 day post partum nor after euthanasia. Necropsy findings in decedent pups and in pups sacrificed on Days 4 and 14 post partum did not reveal any treatment-related effect, as well as in thyroid weight of pups sacrificed on Day 14 post partum. Based on the results of this study, the NOAEL (No Observed Adverse Effect Level) for developmental toxicity was considered to be 800 mg/kg bw/day for both males and females.

Justification for classification or non-classification

According to the CLP Regulation (EC n.1272/2008), reproductive toxicity includes adverse effects on sexual function and fertility in adult males and females, adverse effects on development of the offspring and adverse effects on or via lactation. Substances are classified in Category 1 for reproductive toxicity when they are known to have produced an adverse effect on sexual function and fertility, or on development in humans or when there is evidence from animal studies, possibly supplemented with other information, to provide a strong presumption that the substance has the capacity to interfere with reproduction in humans. Substances are classified in Category 2 for reproductive toxicity when there is some evidence from humans or experimental animals, possibly supplemented with other information, of an adverse effect on sexual function and fertility, or on development, and where the evidence is not sufficiently convincing to place the substance in Category 1. Test substance did not show any evidence of reproductive toxicity in a combined repeated dose toxicity with reproductive/developmental toxicity screening test (OECD TG 422) covering fertility, development and post-partum up to day 13. NOAEL reproductive and developmental toxicity is 800 mg/kg bw/day and the substance Dioctyl phosphonate is not classified for reproductive toxicity according to the CLP Regulation (EC n.1272/2008).