Phosphoric acid, mono- and bis(branched and linear pentyl) esters

Endpoint summary

Description of key information

Acute oral toxicity in rats (OECD 423 guideline study, Kr. 1): LD50 between 2000 and 5000 mg/kg bw.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 2012-06-08 to 2012-12-04

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted in compliance with international standard guidelines under GLP conditions. The study report was well documented with all mandatory information included.

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: 12 NohSan N° 8147, JMAFF, 2002

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

2012-07-09

Test type:

acute toxic class method

Limit test:

no

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories UK Ltd., Oxon, UK
- Age at study initiation: eight to twelve weeks
- Weight at study initiation: The bodyweights fell within an interval of ±20% of the mean initial bodyweight of the first treated group (from 151g to 171 g)
- Fasting period before study: Yes
- Housing: in groups of three in suspended solid-floor polypropylene cages furnished with woodflakes
- Diet (e.g. ad libitum): 2014C Teklad Global Rodent diet supplied by Harlan Laboratories UK Ltd., Oxon, UK
- Water (e.g. ad libitum): free access to mains drinking
- Acclimation period: at least five days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 to 25°C
- Humidity (%): 30 to 70%
- Air changes (per hr): fifteen changes per hour
- Photoperiod (hrs dark / hrs light): the lighting was controlled by a time switch to give twelve hours continuous light (06:00 to 18:00) and twelve hours darkness

IN-LIFE DATES: From: 04 September 2012 To: 11 October 2012

Route of administration:

oral: gavage

Vehicle:

other: DMSO for 300 mg/kg bw and no vehicle for 2000 mg/kg bw

Details on oral exposure:

VEHICLE
For the 300 mg/kg bw dose level:
- Concentration in vehicle: 30 mg/mL
- Amount of vehicle (if gavage): 10 mL/kg bw
- Justification for choice of vehicle: Dimethyl sulphoxide was used because the test item did not dissolve in distilled water or arachis oil
- Lot/batch no. (if required): No data
- Purity: No data

For the 2000 mg/kg dose level: the test item was used as supplied. The specific gravity was determined and used to calculate the appropriate dose volume for the required dose level.The specific gravity used for the calculation was 1.082.

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg bw

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: Based on results with similar susbtances

Doses:

300 mg/kg bw
2000 mg/kg bw

No. of animals per sex per dose:

3 females at 300 mg/kg bw
6 females at 2000 mg/kg bw

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:
+ Observations: The first day: 0.5h, 1h, 2h, 4h and then once daily
+ Weighing: day 0, 7 and 14

- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight

Statistics:

No statistics were performed

Preliminary study:

not applicable

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 - < 5 000 mg/kg bw

Based on:

test mat.

Mortality:

One animal treated at a dose level of 2000 mg/kg bw was killed for humane reasons, two days after dosing, due to the occurrence of clinical signs of toxicity that exceeded the moderate severity limit set forth in the UK Home Office Project Licence. There were no deaths at a dose level of 300 mg/kg bw.

Clinical signs:

other: Hunched posture and ataxia were noted in both dose groups. Additional signs of systemic toxicity noted in animals treated at a dose level of 2000 mg/kg were decreased respiratory rate, gasping, noisy or laboured respiration, pilo-erection, tiptoe gait, pa

Gross pathology:

Abnormalities noted at necropsy of the animal that was humanely killed during the study were haemorrhagic lungs, dark kidneys and epithelial sloughing of the gastric mucosa and non-glandular epithelium of the stomach. No abnormalities were noted at necropsy of animals that were killed at the end of the study.
See Tables 7.2.1/ 6 and 7

Other findings:

No data

Table 7.2.1/2: Individual Clinical Obsevations- 300 mg/kg bw

Dose Level mg/kg bw	Animal Number and Sex	Effects Noted After Dosing (Hours)				Effects Noted During Period After Dosing (Days)
		½	1	2	4	1	2	3	4	5	6	7	8	9	10	11	12	13	14
300	1-0 Female	HA	HA	HA	HA	H	0	0	0	0	0	0	0	Ä	0	0	0	0	0
	1-1 Female	HA	HA	HA	HA	0	0	0	0	0	0	0	0	Ä	0	0	0	0	0
	1-2 Female	HA	HA	HA	HA	0	0	0	0	0	0	0	0	Ä	0	0	0	0	0

 

0 = No signs of systemic toxicity

H = Hunched posture

A = Ataxia

Ä= Due to a technician error observation not performed

Table 7.2.1/3: Individual Clinical Obsevations- 2000 mg/kg bw

 

Dose Level mg/kg bw	Animal Number and Sex	Effects Noted After Dosing (Hours)				Effects Noted During Period After Dosing (Days)
		½	1	2	4	1	2	3	4	5	6	7	8	9	10	11	12	13	14
2000	2-0 Female	H	H	H	(HPSDu SsLWt) H	H	HPWt	HPWtE	HPWtE	HEWt	0	0	0	0	0	0	0	0	0
	2-1 Female	H	H	H	(H) H	H	H	HP	HP	H	0	0	0	0	0	0	0	0	0
	2-2 Female	H	H	H	(HSSm RlWt) H	H	HLRdRgRlRn SeSmSsX*	0	0	0	0	0	0	0	0	0	0	0	0
	3-0 Female	HA	HA	H	H	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-1 Female	H	H	H	H	Rn	Rn	0	0	0	0	0	0	0	0	0	0	0	0
	3-2 Female	H	H	H	H	0	0	0	0	0	0	0	0	0	0	0	0	0	0

 

0 = No signs of systemic toxicity Rd = Decreased respiratory rate Rg = Gasping respiration Rn = Noisy respiration

Rl = Laboured respiration P = Pilo-erection Wt = Tiptoe gait A = Ataxia

E = Pallor of the extremities L = Lethargy Du = Diuresis S = Increased salivation

Se = Red/brown staining around the eyes Sm = Red/brown staining around the mouth Ss = Red/brown staining around the snout

( ) = Observation noted approximately 3 hours after dosing H = Hunched posture

X*= Animal killed for humane reasons due to the occurrence of clinical signs of toxicity that exceeded the moderate severity limit set forth in the UK HomeOffice Project Licence

Table 7.2.1/4: Individual Bodyweights and Weekly Bodyweight Changes - 300 mg/kg bw

Dose Level mg/kg bw	Animal Number and Sex	Bodyweight (g) at Day			Bodyweight Gain (g) During Week
		0	7	14	1	2
300	1-0 Female	165	192	208	27	16
	1-1 Female	171	201	214	30	13
	1-2 Female	162	189	201	27	12

Table 7.2.1/5 Individual Bodyweights and Weekly Bodyweight Changes - 2000 mg/kg bw

Dose Level mg/kg bw	Animal Number and Sex	Bodyweight (g) at Day			Bodyweight (g) at Death	Bodyweight Gain (g) During Week
		0	7	14		1	2
2000	2-0 Female	151	143	123		-8	-20
	2-1 Female	169	172	185		3	13
	2-2 Female	162	-	-	156	-	-
	3-0 Female	163	173	191		10	18
	3-1 Female	159	170	177		11	7
	3-2 Female	147	160	134		13	-26

- = Animal dead

Table 7.2.1/6 Individual Necropsy Findings - 300 mg/kg bw

Dose Level mg/kg bw	Animal Number and Sex	Time of Death	Macroscopic Observations
300	1-0 Female	Killed Day 14	No abnormalities detected
	1-1 Female	Killed Day 14	No abnormalities detected
	1-2 Female	Killed Day 14	No abnormalities detected

Table 7.2.1/7 Individual Necropsy Findings - 2000 mg/kg bw

Dose Level mg/kg bw	Animal Number and Sex	Time of Death	Macroscopic Observations
2000	2-0 Female	Killed Day 14	No abnormalities detected
	2-1 Female	Killed Day 14	No abnormalities detected
	2-2 Female	Humanely killed Day 2	Lungs: haemorrhagic Kidneys: dark Gastric mucosa: epithelial sloughing Non-glandular epithelium of the stomach: epithelial sloughing
	3-0 Female	Killed Day 14	No abnormalities detected
	3-1 Female	Killed Day 14	No abnormalities detected
	3-2 Female	Killed Day 14	No abnormalities detected

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The acute oral median lethal dose (LD50) of the test item in the female Wistar strain rat was estimated to be greater than 2000 mg/kg bodyweight.

Executive summary:

In an acute oral toxicity study, performed according to acute toxicity class method Procedure (OECD Guideline 423; EC test method B1.tris, EPA OPPTS870.1100 and Japanese MAFF, 2000) and in compliance with the GLP, groups of female Wistar rats were given a single oral dose of Phosphoric acid, mono- and bis(branched and linear pentyl) esters by gavage at the dose of 300 or 2000 mg/kg bw. The test item was administered as supplied for the dose of 2000 mg/kg bw and diluted in DMSO for the lowest dose of 300 mg/kg bw. Clinical signs, mortality and body weight gain were checked for a period of up to 14 days. All surviving animals were sacrificed at the end of the study and necropsied for gross abnormalities.

 

The starting dose was stated as 300 mg/kg bw and tested in a group of 3 female rats. As no mortality occurred and no severe clinical signs were observed,two groups of 3 female rats further fasted were given a single oral dose of 2000 mg/kg bw. At this dose, one animal was killed for ethical reasons 2 days after dosing, due to the occurrence of clinical signs of toxicity that exceeded the moderate severity limit set in the UK Home Office Project Licence. Hunched posture and ataxia was noted in both dose groups (300 and 2000 mg/kg bw). Additional signs of systemic toxicity noted in animals treated at a dose level of 2000 mg/kg bw were decrease respiratory rate, gasping, noisy or labored respiration, pilo-erection, tiptoe gait, pallor of the extremities, lethargy, diuresis, increased salivation and red/brown staining around the eyes and snout. No clinicals signs were observed from Day 7 up to the end of the observation period. Furthermore, two animals exposed to the dose of 2000 mg/kg bw showed body weight loss during the study. No abnormalities were detected at the necropsy at the end of the study. The rat killed on day 2 showed haemorrhagic lung, dark kidneys, epithelial sloughing in gastric mucosa and in non glandular epithelium of the stomach.

Under these experimental conditions, the Ld50 in rat was determined to be higher than 2000 mg/kg bw. Therefore no classification for acute oral toxicity is required for Phosphoric acid, mono- and bis(branched and linear pentyl) esters neither according to the criteria of the Regulation (EC) 1272/2008 (CLP including ATP3) nor according to the criteria of the Directive 67/548/EEC.

This study is considered as acceptable and satisfies the requirement for acute oral toxicity endpoint.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

Key study performed according to the 0ECD 423 guideline study and in compliance with the GLP (Klimisch score = 1). Furthermore, the study on structural analog showed similar results (LD50 > 2000 mg/kg bw). Thus the overall quality of the database is high.

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Quality of whole database:

waiving based on the corrosive properties of the submitted substance.

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Quality of whole database:

waiving based on the corrosive properties of the submitted substance.

Additional information

In an acute oral toxicity study, performed according to acute toxicity class method Procedure (OECD test Guideline 423) and in compliance with the GLP, groups of female Wistar rats were given a single oral dose of Phosphoric acid, mono- and bis(branched and linear pentyl) esters by gavage at the dose of 300 or 2000 mg/kg bw. The test item was administered as supplied for the dose of 2000 mg/kg bw and diluted in DMSO for the lowest dose of 300 mg/kg bw.  

The starting dose was stated as 300 mg/kg bw and tested in a group of 3 female rats. As no mortality occurred and no severe clinical signs were observed,two groups of 3 female rats further fasted were given a single oral dose of 2000 mg/kg bw. At this dose, one animal was killed for ethical reasons 2 days after dosing.

Hunched posture and ataxia was noted in both dose groups (300 and 2000 mg/kg bw). Additional signs of systemic toxicity noted in animals treated at a dose level of 2000 mg/kg bw were decrease respiratory rate, gasping, noisy or labored respiration, pilo-erection, tiptoe gait, pallor of the extremities, lethargy, diuresis, increased salivation and red/brown staining around the eyes and snout. No clinicals signs were observed from Day 7 up to the end of the observation period. Furthermore, two animals exposed to the dose of 2000 mg/kg bw showed body weight loss during the study. No abnormalities were detected at the necropsy at the end of the study. The rat killed on day 2 showed haemorrhagic lung, dark kidneys, epithelial sloughing in gastric mucosa and in non glandular epithelium of the stomach.

Under these experimental conditions, the LD50 in rat was determined to be higher than 2000 mg/kg bw.

According to the Annex VIII of REACH, a second route (in addition to the oral route) is needed to complete a dossier regarding the acute toxicity. However, if the registered is classified as corrosive to the skin, no further test has to be performed. Since the submitted substance is classified as corrosive (Skin Corr. 1B, H314 or C, R34), there is no datagap regarding the Acute toxicity endpoint.

Justification for selection of acute toxicity – oral endpoint
The Key study is selected: this study was performed on the submitted substance whereas the other one available study was conducted on an analogue substance.

Justification for classification or non-classification

Harmonized classification:

No harmonized classification is available according to the Regulation (EC) No 1272/2008 including ATP3.

Self classification:

Phosphoric acid, mono- and bis(branched and linear pentyl) esters is not classified for acute oral toxicity according to the Regulation (EC) 1272/2008 (CLP) and to the Directive 67/548/EEC as the oral LD50 (rats) is higher than 2000 mg/kg bw.

Phosphoric acid, mono- and bis(branched and linear pentyl) esters is not classified for acute dermal and inhalation toxicity due to a lack of data.