Phosphorus

Acute Toxicity: other routes

Administrative data

Endpoint:

acute toxicity: other routes

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Data source

Reference

Reference Type:

publication

Title:

Biochemistry, histopathology and treatment of phosphorus burns. An experimental study

Author:

Ben-Hur N & Appelbaum J

Year:

1973

Bibliographic source:

Isr J Med Sci 9: 40-48

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

The study investigated the systemic effects caused by acute phosphorus burns, only target organs were evaluated.

GLP compliance:

not specified

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Phosphorus

EC Number:

231-768-7

EC Name:

Phosphorus

Cas Number:

7723-14-0

Molecular formula:

P

IUPAC Name:

phosphorus

Test material form:

solid

Details on test material:

Elemental phosphorus is often referred to as yellow phsophorus

Test animals

Species:

rat

Strain:

not specified

Sex:

male

Details on test animals or test system and environmental conditions:

The animals were male rats weighing 250 g. Rats were housed in metabolic cages during the experiment.

Administration / exposure

Route of administration:

other: intradermal burns

Vehicle:

unchanged (no vehicle)

Details on exposure:

Rats were anaesthetised with pentobarbital sodium i.p. then 25 mg of white phosphorus was introduced into the inguinal region by means of a 1.5 cm incision through the epidermis and dermis. The phosphorus was ignited by touching it with hot metal and allowing it to burn for 4 minutes by alternately closing and opening the wound. Following he burn the wound was sutured.

Doses:

25 mg white phosphorus

No. of animals per sex per dose:

96 rats (divided into 12 groups of 8 all identically treated) exposed to white phosphorus, and 48 rats (divided into 12 groups of 4 rats all indentically treated) were sham-exposed.

Control animals:

yes

Details on study design:

Rats were anaesthetised with pentobarbital sodium i.p. then 25 mg of white phosphorus was introduced into the inguinal region by means of a 1.5 cm incision through the epidermis and dermis. Controls were subject to the same procedure with the exception of the introduction of phosphorus. Urine was collected in the metabolism cages, and blood was collected from the tail vein for urinalysis and blood chemistry. Rats were sacrificed at intervals up to and including 72 hours post-burn for histopathological examination of the kidneys and liver.

Statistics:

No information given

Results and discussion

Effect levels

Sex:

male

Dose descriptor:

LD50

Effect level:

25 other: mg

Mortality:

50% of the rats died within 3-4 days of receiving the phosphorus burn

Clinical signs:

Not reported

Body weight:

Not reported

Gross pathology:

Not reported

Other findings:

In most of the phosphorus treated animals, the burned area began to smoke when the wound was opened. The burn surface was necrotic and yellowish, smelled of garlic for 2 days and glowed in the dark. The wound did not demonstrate any tendency to heal for six days following the burn.
The biochemical changes 72 hours post-burn are shown in Table 1.

Any other information on results incl. tables

Biochemical results taken from all experiments 72 hours after the burn

Parameter	Control rats	Rats subjected to phosphorus burns
Water intake (ml/24 hr)	15 - 18	40 - 50
Urinary output (ml/24 hr)	10 - 12	30 - 40
Serum phosphorous (mg/100 ml)	4 - 5	9 - 11
Serum urea (mg/100 ml)	10 - 20	90 - 110
Serum Na (mEq/L)	135 - 140	125 - 130
Serum K (mEq/L)	4 - 5	7 - 9
SGPT (units/ml)	9 - 11	90 - 110
Serum osmolarity (mOsm/L)	284 - 300	340 - 360
Urine osmolarity (mOsm/L)	2000 - 2200	680 - 720
Creatinine clearance (ml/min)	1.2 - 1.3	0.7 - 0.8

The differences between treated and control rats were significant at P < 0.01.

Applicant's summary and conclusion

Conclusions:

50% of the rats died within 3-4 days of receiving the phosphorus burn

Executive summary:

50% of rats died within 3-4 days of receiving a phosphorus burn. Alterations in serum phosphate, sodium and potassium levels and 72 hours after the burn were throught to correspond to renal failure, further backed up by the high urine output and decrease in creatinine clearance. Histology results were not reported for these animals, although the authors summarise that the burns resulted in primary renal damage followed by functional alterations, diffuse liver changes and severe changes in blood and urine composition. They conclude that early death is likely to be caused by primary renal alterations and cardiac arrest from potassium intoxication.