Registration Dossier

Administrative data

Description of key information

In a well conducted study (Biodynamics Inc., 1985), doses of 2000, 2500, 3200 and 4000 mg/kg bw HEDP-4Na was administered to rats (5/sex) by oral gavage. Animals were observed for 14 days. Ataxia and/or tremors, oral and nasal discharge, hypoactivity, soft stool and fecal and/or urinary staining were observed at all doses. The majority of surviving animals showed some weight loss during the 1st week after dosing, but all animals then gained weight between days 7 and 14. Macroscopic abnormalities observed at necropsy were primarily changes suggestive of irritation: lungs (discolouration) and gastrointestinal tract (red or black walls, or red or black fluid present).  Most of the animals in the 2500, 3200 and 4000 mg/kg dose groups had enlarged kidneys at necropsy, and one animal in the 4000 mg/kg bw group had unilateral renal pallor, dilated renal pelvis and red fluid surrounding the kidney. The LD50 was 2850 mg/kg bw (subsequently calculated to be equivalent to 940 mg active salt/kg bw). In an acute dermal toxicity limit test (Biodynamics Inc., 1985) 5000 mg/kg bw of HEDP-4Na was applied to the skin of rabbits (5/sex, occlusive dressing, 24 hours). Animals were then observed for 14 days. One female died on Day 13 (not test-related). Most animals had severe dermal effects at the dose site (necrosis followed by eschar formation and/or exfoliation of the eschar tissue), which persisted throughout the observation period.  The LD50 was determined to be >5000 mg/kg bw.  There are no acute inhalation data.

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:
12.03.1985 to 17.04.1985 (inclusive of limit, range-finder and LD50 tests)
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:
OECD Guideline 401 (Acute Oral Toxicity)
Deviations:
yes
Remarks:
no post-dose fast
Principles of method if other than guideline:
Bio/dynamics protocol based on US guidelines. Broadly compatible with OECD guideline.
GLP compliance:
no
Test type:
standard acute method
Limit test:
no
Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Breeding Laboratories
- Age at study initiation: 9-12 weeks
- Weight at study initiation: 220-329 g
- Fasting period before study: 18 hours overnight prior to dosing
- Housing: Six per cage (suspended, stainless steel with wire mesh bottoms
- Diet (e.g. ad libitum): Ad libitum
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: At least 9 days


ENVIRONMENTAL CONDITIONS
- Temperature (°F): 67-76
- Humidity (%): 30-70
- Air changes (per hr): No data
- Photoperiod (hrs dark / hrs light): 12/12


IN-LIFE DATES: Limit test: From: 21.03.85 To: 22.03.85
Range-finding test: From: 27.03.85 To: 03.04.85
LD50 test: From: 03.04.85 To: 17.03.85
Route of administration:
oral: gavage
Vehicle:
unchanged (no vehicle)
Details on oral exposure:
MAXIMUM DOSE VOLUME APPLIED: 3.8 ml/kg in the limit test, 1.5 ml/kg in the range-finding test, and 3.1 ml/kg in the LD50 test.
Doses:
Limit test: 5000 mg/kg bw.
Range-finding test: 50, 100, 500, 1000 and 2000 mg/kg bw
LD50 determination: 2000, 2500, 3200 and 4000 mg/kg bw
No. of animals per sex per dose:
Limit test: 5
Range-finding test: 1
LD50 determination: 5
Control animals:
no
Details on study design:
Animals used in the range-finding test were observed for viability twice daily and deaths were recorded. The following observations were made on all other animals:
Viability check: twice daily.
Clinical signs: approximately 1, 2 and 4 hours after dosing and daily thereafter for 14 days
Body weights: pre-fasting, post-fast, just prior to dosing), and Days 7 and 14 after dosing.
Macroscopic examination: Not on range-finding test animals. A macroscopic examination was conducted on all other animals.
Statistics:
The LD50 with 95% confidence limits was calculated using the method of Miller, Lloyd C. and M.L. Tainter., Estimation of the ED50 and its error by means of Logarithmic-Probit graph paper, Proc.Soc.Exp.Bio.Med. 57: 261-264 (1944).
Key result
Sex:
male/female
Dose descriptor:
LD50
Effect level:
2 850 mg/kg bw
95% CL:
>= 2 489 - <= 3 211
Remarks on result:
other: presumed equivalent to 940 mg active salt/kg bw
Mortality:
RANGE FINDING TEST: No deaths at any dose level. 
LD50 DETERMINATION TEST/LIMIT TEST At 2000 mg/kg, 1 animal died (day 3 after dosing) 
At 2500 mg/kg, 4 animals died (1-4 hours after dosing) 
At 3200 mg/kg, 7 animals died (1 hour - day 8 after dosing) 
At 4000 mg/kg, 8 animals died (1-4 hours after dosing) 
At 5000 mg/kg, all 10 animals died (2-7 hours after dosing)
Clinical signs:
LD50 determination: Observations in all groups for up to four hours post-dosing, included ataxia and/or tremors, oral and nasal discharge, hypoactivity, soft stool and fecal and/or urinary staining.  
Body weight:
LD50 determination: The majority of surviving animals showed some weight loss during the first week after dosing, but all animals then gained weight between days 7 and 14.
Gross pathology:
LD50 determination: Macroscopic abnormalities observed at necropsy were primarily changes to the lungs (discolouration) and gastrointestinal tract (red or black walls, or red or black fluid present, suggestive of an irritant effect).  Most of the animals in the 2500, 3200 and 4000 mg/kg dose groups had enlarged kidneys at necropsy, and one animal in the 4000 mg/kg bw group had unilateral renal pallor, dilated renal pelvis and red fluid surrounding the kidney. 
Other findings:
None reported.

Table 1 Summary of deaths in LD50 determination study.

 Dose   Mortality       Time to death
 mg/kg bw  Males  Females  Combined  
 2000  1/5  0/5  1  day 3
 2500  1/5  3/5  4  1 -4 h
 3200 3/5  4/5  7  1 h to day 8
 4000  4/5  4/5  8  1 -4 h
 5000  5/5  5/5  10  2 -7 h
 LD50  3100  2500  2850  
 95% conf limit  2365 -3635  1802 -3198  2489 -3211  




Interpretation of results:
Category 4 based on GHS criteria
Conclusions:
Based on the results of a well conducted acute oral study (reliability score 2), conducted using a protocol similar to the now deleted OECD 401, but not to GLP, an LD50 of 2850 mg/kg (reviewer for IUCLID 4 comment: presumed equivalent to 940 mg active salt/kg bw) was determined for Dequest 2016 in the rat.
Executive summary:

In a well conducted, non-GLP study, 5000 mg/kg bw undiluted Dequest 2016 was given to five Sprague-Dawley rats by oral gavage in a limit test. Within seven hours all of the animals had died. Therefore a range-finding study and subsequent LD50 determination were performed. In the range-finding study, doses of 50, 100, 500, 1000 and 2000 mg/kg bw were administered to one male and one female Sprague-Dawley rat. Based on the findings of this study, doses of 2000, 2500, 3200 and 4000 mg/kg bw Dequest 2016 were administered to Sprague-Dawley rats (5/sex) by oral gavage. Animals were observed for 14 days following dosing, and all animal were examined macroscopically. Body weights were recorded before dosing and on days 7 and 14. One, 4, 7 and 8 animals died, respectively. Observations in all groups for up to four hours post-dosing, included ataxia and/or tremors, oral and nasal discharge, hypoactivity, soft stool and fecal and/or urinary staining. The majority of surviving animals showed some weight loss during the first week after dosing, but all animals then gained weight between days 7 and 14. Macroscopic abnormalities observed at necropsy were primarily changes to the lungs (discolouration) and gastrointestinal tract (red or black walls, or red or black fluid present, suggestive of an irritant effect).  Most of the animals in the 2500, 3200 and 4000 mg/kg dose groups had enlarged kidneys at necropsy, and one animal in the 4000 mg/kg bw group had unilateral renal pallor, dilated renal pelvis and red fluid surrounding the kidney. The LD50 was calculated to be 2850 mg/kg bw (subsequently calculated to be equivalent to 940 mg active salt/kg bw).

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
2 850 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
no study available

Acute toxicity: via dermal route

Link to relevant study records
Reference
Endpoint:
acute toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Study period:
04.03.1985 to 02.04.1985
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:
OECD Guideline 402 (Acute Dermal Toxicity)
GLP compliance:
no
Test type:
standard acute method
Limit test:
yes
Species:
rabbit
Strain:
New Zealand White
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Hazleton-Dutchland Laboratory animals
- Age at study initiation: 8 weeks
- Weight at study initiation: Males: 2.2-2.7 kg. Females: 2.5-2.7 kg
- Fasting period before study: No
- Housing: Individually, in suspended stainless steel cages
- Diet (e.g. ad libitum): Ad libitum
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: 15 days


ENVIRONMENTAL CONDITIONS
- Temperature (°F): 60-70
- Humidity (%): 30-70
- Air changes (per hr): No data
- Photoperiod (hrs dark / hrs light): 12/12


IN-LIFE DATES: From: 19.03.85 To: 02.04.85
Type of coverage:
occlusive
Vehicle:
other: aqueous solution, administered undiluted.
Details on dermal exposure:
TEST SITE
- Area of exposure: Dorsal area of the trunk
- % coverage: 10% of body surface area
- Type of wrap if used: Impervious plastic sleeve


REMOVAL OF TEST SUBSTANCE
- Washing (if done): test sites wiped free of excess test substance
- Time after start of exposure: 24 hours


TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 3.8 ml/kg
Duration of exposure:
24 hours
Doses:
5000 mg/kg bw
No. of animals per sex per dose:
Five
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Viability: Twice daily. Clinical signs: 1, 2, and 4 hours after dosing and then daily for 14 days. Body weights: Pretest, immediately prior to dosing and days 7 and 14.
- Necropsy of survivors performed: yes
- Other examinations performed: Macroscopic examination of all animals.
Statistics:
None
Key result
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 5 000 mg/kg bw
Remarks on result:
other: Presumed equivalent to >1650 mg active salt/kg bw (IUCLID 4)
Mortality:
One female died on Day 13. However, macroscopic examination revealed signs of intestinal disease that was not thought to be related to the test substance. All other animals survived to the end of the observation period.
Clinical signs:
In all surviving animals there were some occurrences of oral and nasal discharge. Most animals had severe dermal effects at the dose site (necrosis followed by eschar formation and/or exfoliation of the eschar tissue), which persisted throughout the observation period.
Body weight:
Most animals had slight weight losses at Days 7 and/or 14.
Gross pathology:
The female that was found dead had gross abnormalities suggestive of mucoid enteritis. Apart from the presence of dermal lesions, there were no abnormal findings in the other animals.
Other findings:
None reported.
Interpretation of results:
GHS criteria not met
Conclusions:
In a well-conducted acute dermal toxicity limit test, conducted according to a protocol that was similar to OECD 402, but not to GLP, the dermal LD50 for Dequest 2016 was >5000 mg/kg bw (IUCLID 4 reviewer comment: presumed equivalent to >1650 mg active salt/kg bw) in the rabbit.
Executive summary:

In a well-conducted acute dermal toxicity limit test, conducted according to a protocol that was similar to OECD 402, but not to GLP, 5000 mg/kg bw of Dequest 2016 was applied to the skin of New Zealand white rabbits (5/sex) under an occlusive dressing, for 24 hours. After the 24 hour exposure period excess test substance was wiped off the test site. Animals were then observed for 14 days for signs of toxicity, and body weights were measured prior to dosing and on days 7 and 14. All animals were examined macroscopically. One female died on Day 13. However, macroscopic examination revealed signs of intestinal disease that was not thought to be related to the test substance. All other animals survived to the end of the observation period. In all surviving animals there were some occurrences of oral and nasal discharge. Most animals had severe dermal effects at the dose site (necrosis followed by eschar formation and/or exfoliation of the eschar tissue), which persisted throughout the observation period. Most animals had slight weight losses at Days 7 and/or 14. The female that was found dead had gross abnormalities suggestive of mucoid enteritis. Apart from the presence of dermal lesions, there were no abnormal findings in the other animals. The LD50 was determined to be >5000 mg/kg bw.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
5 000 mg/kg bw

Additional information

The most recent reliable study was selected as the key studies.

Justification for classification or non-classification

It is proposed that tetrasodium HEDP be classified as ‘Acute Oral Cat. 4’under Annex VI of Regulation 1272/2008; hence 'H302: Harmful if swallowed'.

There is no proposal to classify tetrasodium HEDP for acute dermal toxicity.