Petrolatum

Endpoint summary

Description of key information

The acute toxicity of petrolatum (carcinogenic or unknown feed-stock and non-carcinogenic feed-stock) is low with no observed mortalities from oral or dermal applications.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

5 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Value:

mg/m³ air

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Additional information

Sufficiently refined and insufficiently refined petrolatums have low acute toxicity with an oral LD₅₀ greater than 5000 mg/kg (in rat) and a dermal LD₅₀ of greater than 2000 mg/kg (in rabbit).

Insufficiently Refined Petrolatum (Carcinogenic or Unknown Feed-stock)

No acute oral or dermal toxicity studies have been reported for insufficiently refined petrolatum, but data have been reported for unrefined/acid treated lubricant base oils, materials similar to the oil entrained in insufficiently refined petrolatum.

Acute Oral Toxicity:

One key read-across study (API, 1986a) was identified to evaluate the acute oral toxicity potential of insufficiently refined petrolatum. In this acute oral toxicity study, groups of fasted, 7 week old Sprague-Dawley albino rats (5 male/5 female) were given a single oral dose of light paraffinic distillate at a dose of 5000 mg/kg bw and observed for 14 days. Clinical signs observed during the study included: hypoactivity, diarrhoea, and yellow-stained anal area. All animals had returned to normal by study day 4. There were no mortalities during this study. Necropsy pathology discovered no visible lesions on any of the animals. The oral LD₅₀ was determined to be greater than 5000 mg/kg of body weight in both males and females.

Acute Dermal Toxicity:

One key read-across study (API, 1986a) was identified to evaluate the acute dermal toxicity potential of insufficiently refined petrolatum. In this acute dermal toxicity study, groups of 14 week old New Zealand White rabbits (4 male/4 female) were dermally exposed to light paraffinic distillate for 24 hours to 10% of body surface area at a single dose of 2000 mg/kg bw. Animals then were observed for 14 days. With the exception of dermal irritation, the only clinical sign observed was soft stool on study day 4 for one male and three female animals. Dermal irritation observed during the study ranged from slight to severe for erythema and oedema, from slight to marked for fissuring, and from slight to moderate for atonia and desquamation. Slight coriaceousness was also observed. One male animal exhibited a body weight loss at days 7 and 14 weighings. This animal had an abraded test site. The dermal LD₅₀ was determined to be greater than 2000 mg/kg of body weight for both males and females.

Inhalation toxicity studies were not reported for insufficiently refined petrolatum since inhalation is not an expected route of exposure due to the very low vapour pressure of these substances.

 

Sufficiently Refined Petrolatum (Non-carcinogenic Feed-stock)

 Only one acute toxicity study has been reported for sufficiently refined petrolatum. No acute dermal toxicity studies have been reported for sufficiently refined petrolatum, but data have been reported for other lubricant base oils (IP 346 <3%) and paraffin and hydrocarbon waxes, materials similar to sufficiently refined petrolatum.

Acute Oral Toxicity:

Two key read-across studies (API, 1982a and IBR, 1976) were identified to evaluate the acute oral toxicity potential of sufficiently refined petrolatum.

In one key read-across study (API, 1982a), paraffinic oil sample API 78-9 (Other lubricant base oil, IP 346 <3%; CAS No. 64742-56-9) was administered via oral gavage to 5 Sprague-Dawley rats per sex at a single dose of 5,000 mg/kg (5 g/kg). The rats were observed for clinical signs of toxicity, changes in body weight, and other gross abnormalities over a 14-day post-exposure observation period. All rats were killed and necropsied on day 14. No mortalities or any sign of clinical sign of toxicity were observed in either male or female rats dosed at 5,000 mg/kg. Body weight gain was observed to be normal in all animals. One animal did exhibit hydronephrosis in the right kidney but this was not considered to be treatment-related. Necroscopy did not reveal any gross abnormalities in either male or female rats. Acute oral LD₅₀ >5,000 mg/kg (5 g/kg). Paraffinic oil 78-9 was observed to be practically non-toxic when administered orally via gavage to Sprague-Dawley rats.

In another key read-across acute oral toxicity study (IBR, 1976), groups of fasted, SFP Wistar rats (5/sex) were given a single oral dose of R 9107 (Paraffin wax) in arachis oil at doses of 1000 or 5000 mg/kg bw and observed for 7 days. There were no treatment related clinical signs, necropsy findings or changes in body weight. Based on the lack of systemic toxicity effects and mortality, the oral LD₅₀ was determined to be >5000 mg/kg bw (male and female).

In a supporting acute oral toxicity test (Lawall and Harrison Research Laboratories, 1969), no mortality was observed in male rats orally administered oxidized petrolatum (CAS# 64743-01-7) in warm corn oil at a dose of 5000 mg/Kg. Supporting studies conducted in rats (BIBRA, 1993a; 1993b; CTFA, 1984) and dogs (CTFA, 1984) with paraffin and hydrocarbon waxes also indicate that the acute oral LD₅₀ is >5000 mg/Kg.

Acute Dermal Toxicity:

Two key read-across studies (BIBRA, 1993c and API, 1982b) were identified to evaluate the acute dermal toxicity potential of sufficiently refined petrolatum.

In a read-across study (BIBRA, 1993c), groups of five male and five female young adult Sprague-Dawley rats were dermally exposed to paraffin wax (SX30) for 24 hours to approximately 10% of body surface at a dose of 2000 mg/kg body weight. Animals then were observed for 14 days. The test article caused slight skin irritation reactions in a majority of treated animals which persisted throughout the study. However, a previous study performed at BIBRA (Report No.1091(3) /1/93) demonstrated that SX30 is only a mild irritant and has no corrosive (irreversible) properties when applied to intact rabbit skin for 4 hours. Based on the absence of mortality, minimal clinical observations, standard body weight and weight gain, and necropsy results, the dermal LD₅₀ was determined to be > 2000 mg/kg body weight.     

In another read-across acute dermal toxicity study (API, 1982b), groups of New Zealand white rabbits (2/male and 2/ female) were dermally exposed to lubricant base oil API 78 -10 for 24 hours at doses of 2000 or 5000 mg/Kg bw. There were no mortalities in any of the studies. The only clinical signs were skin irritation and the occurrence of soft stool in some animals, but this latter effect was transient. Skin irritation ranged from slight to severe for erythema and oedema; slight to marked for atonia, desquamation, and fissuring; and from slight to moderate for coriaceousness. The LD₅₀s were greater than the doses that had been applied (i.e.2000 or 5000 mg/Kg).

Supporting studies conducted in rabbits (CTFA, 1972a; Elder, 1984) with a 50% solution of paraffin wax in petrolatum at a dose of 3600 mg/kg (closed-patch exposure for 24 hours) did not indicate any systemic effects or abnormalities. The acute dermal LD₅₀ was therefore determined to be >3600 mg/kg. Additional supporting studies conducted in rabbits (API, 1982c; 1982d; 1982e) have reported acute dermal LD₅₀s of >5000 mg/Kg for lubricant base oils (IP 346 <

Inhalation toxicity studies were not reported for sufficiently refined petrolatum since inhalation is not an expected route of exposure due to the very low vapour pressure of these substances.

Justification for selection of acute toxicity – oral endpoint

One of 11 acute oral toxicity studies available.

Justification for selection of acute toxicity – dermal endpoint

One of 7 acute dermal toxicity studies available.

Justification for classification or non-classification

Based on the available data, sufficiently refined and insufficiently refined petrolatums do not meet the EU CLP (EC No. 1272/2008) criteria for acute oral, dermal, or inhalation toxicity and are not classified.