Zinc, O,O-mixed (iso-Bu), (iso-Pr), (pentyl) phosphorodithioate

Endpoint summary

Description of key information

oral route:

source substance Zinc bis(O,O-diisobutyl dithiophosphate) (CAS 68457 -79 -4): non GLP, similar to OECD Guideline 401, Klimisch 1, rat, oral (gavage), LD50 = 3600 mg/kg bw

source substance Zinc bis[O,O-bis(2-ethylhexyl)] bis(dithiophosphate) (CAS 4259 -15 -8): non GLP, similar to OECD Guideline 401, Klimisch 2, rat, oral (gavage), LD50 = 3100 mg/kg bw

source substance Phosphorodithioic acid, mixed O,O-bis(1,3 -dimethylbutyl and iso-Pr) esters, zinc salts (CAS 84605 -29 -8): non GLP, similar to OECD 401, Klimisch 1, rat, oral (gavage), LD50 = 3100 mg/kg bw

inhalative route:

source substance Phosphorodithioic acid, mixed O,O-bis(1,3 -dimethylbutyl and iso-Pr) esters, zinc salts (CAS 84605 -29 -8): non GLP, similar to OECD 403, Klimisch 2, rat, inhalation (vapour) - whole body, 4 h, LD50 > 2.3 mg/L air (nominal)

dermal route:

source substance Zinc bis(O,O-diisobutyl dithiophosphate) (CAS 68457 -79 -4): GLP, similar to OECD 402 - according to 16CFR1500.3, Klimisch 2, rabbit, dermal - occlusive, 25 h, LD50 > 20000 mg/kg bw

source substance Phosphorodithioic acid, mixed O,O-bis(1,3 -dimethylbutyl and iso-Pr) esters, zinc salts (CAS 84605 -29 -8): GLP, similar to OECD 402, Klimisch 2, rat, dermal - semiocclusive, 25 h, LD50 > 2002 mg/kg bw

source substance Zinc bis[O,O-bis(2-ethylhexyl)] bis(dithiophosphate) (CAS 4259 -15 -8): non GLP, similar to OECD 402, Klimisch 2, rabbit, dermal - occlusive, 24 h, LD50 > 5000 mg/kg bw

Based on the available data and based on the performed studies for CSA as key value the lowest value of all category members was choosen. Differences in the values of each category-member are obvious, but this is in range with the category approach, where nevertheless the members of one category may have different values, because all results show, that no substance has to be classified according to CLP (Regulation (EC) No 1272/2008).

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

3 100 mg/kg bw

Quality of whole database:

High due to high quality guideline studies

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LC50

Value:

2 300 mg/m³ air

Quality of whole database:

Good due to well documented study comparable to guideline study

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 002 mg/kg bw

Quality of whole database:

High due to high quality guideline studies

Additional information

Source substance Zinc bis(O,O-diisobutyl dithiophosphate) (CAS 68457 -79 -4):

oral route:

Male Wistar rats were exposed to test substance at doses of 2.0, 3.5, 5.0 and 8.75 g/kg. The oral LD50 is 3.6 g/kg. Sublethal effects of lethargy, diarrhea, piloerection, chromodacryorrhea, chromorhinorrhea and ptosis were observed. Necropsy observations included lung and gastrointestinal abnormalities (Moreno 1979).

dermal route:

In an acute dermal toxicity study similar to OECD Guideline 402, New Zealand White rabbits were exposed to 20 g/kg of the test substance. The LD50 on Day 14 post-exposure was greater than 20 g/kg. Toxic signs observed included lethargy, diarrhea, ataxia, ptosis, alopecia, emaciation, and yellow nasal discharge. Based on the results of this study, the test substance would not be classified in accordance with CLP. This toxicity study is classified as acceptable and satisfies the guideline requirement for acute dermal toxicity in rabbits.

 

Source substance Zinc bis[O,O-bis(2-ethylhexyl)] bis(dithiophosphate) (CAS 4259 -15 -8):

oral route:

Sublethal effects of depression, diarrhea, and reduced food intake were observed. Necropsy observations included reduction of body fat, no specific organ toxicity is evident (Bullock 1975).

dermal route:

This substance does not show any evidence of toxicity via the dermal route of exposure in animals when tested in accordance with OECD Guideline 402. The dermal LD50 is greater than 5000 mg/kg in male rabbits. Severe erythema and edema noted at 24 hours. Necrotic-appearing areas of lung tissue observed in five rabbits. Further histology of the lungs revealed confluent bronchopneumonia or chronic interstitial pneumonia.

 

Source substance Phosphorodithioic acid, mixed O,O-bis(1,3 -dimethylbutyl and iso-Pr) esters, zinc salts (CAS 84605 -29 -8):

oral route:

The substance does not show any evidence of toxicity via the oral route of exposure in animals when tested similar to OECD Guideline 401. The rat oral LD50 is 3,200 mg/kg in male and 3,100 mg/kg in female rats. Sublethal effects included hypokinesia and diarrhea; necropsy observations were unremarkable; no specific organ toxicity is evident; all animals showed expected bodyweight gain during the course of study.

inhalative route:

In an acute inhalation toxicity study similar to OECD guideline 403 (no GLP conditions), male and female rats were exposed to test substance at a nominal concentration of 2.3 mg/l under continuous air flow conditions for 4 h. The LC50 is >2.3 mg/l. Diarrhea was noted in one animal, all other animals appeared normal. Based on the results of this study, the test substance would be unclassifiable in accordance with the classification system of GHS. The LC50 only eliminates Category 1 or 2 classification.This toxicity study is classified as acceptable and satisfies the guideline requirement for acute inhalation toxicity in rats.

dermal route:

This substance does not show adverse toxicity effects via the dermal route of exposure in animals when tested in accordance with OECD Guideline 402. The rat dermal LD50 is greater than 2002 mg/kg in male rabbits. Prostration in one animal, and desquamation of the skin noted on test day 11 were observed. No specific organ toxicity is evident.

Justification for classification or non-classification

Based on the results for the source substances the registered substance does not have to be classified according to Regulation (EC) No 1272/2008.

oral: LD50 > 3100 mg/kg bw

inhalative: LC50 > 2300 mg/m³ (no higher concentration reachable, because no adverse effects at this concentration observed, therefore no classifcation was done)

dermal: LD50 > 2002 mg/kg bw