Overbased reaction products of distilled tall oil and magnesium hydroxide’

Endpoint summary

Description of key information

Not acutely toxic following oral or dermal exposure (LD50 >2000 mg/kg bw in both instances). Low vapour pressure precludes inhalation exposure.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Additional information

Acute oral toxicity

Results from investigations into the acute toxicity of salts of unsaturated fatty acids, resin and rosin acids and supporting data on rosin and rosin reaction products are summarised briefly below:

In a key acute oral toxicity study in the rat (Bradshaw, J., 2010),female Wistar rats were given a single oral dose of fatty acids, C18-(unsaturated) lithium salts, as a suspension in distilled water, at a dose levels of either 300 (n=1) or 2000 (n=5) mg/kg bodyweight. No mortality was observed through the study period. Signs of toxicity noted in animals treated at a dose level of 2000 mg/kg were hunched posture, pilo-erection, ataxia, noisy respiration, sneezing and increased salivation. There were no signs of toxicity noted in the single animal treated at a dose level of 300 mg/kg. No abnormalities were observed in animals at necropsy. The acute oral LD₅₀ was determined to be greater than 2000mg/kg bodyweight.

 

In a second study, Resin acids and rosin acids, magnesium salts was administered to six female rats at a dose level of 2000 mg/kg bw after formulation in olive oil (Phycher Bio Development, 2010b). At all the observation points up to the termination of the study on day 14, no mortalities, clinical signs or macroscopic abnormalities were observed. The oral LD₅₀ of the test item was greater than the limit dose of 2000 mg/kg bw.

In another study, Resin acids and rosin acids, calcium zinc salts was administered to six female rats at a dose level of 2000 mg/kg bw after formulation in olive oil (Phycher Bio Development, 2010a). At all the observation points up to the termination of the study on day 14, no mortalities, clinical signs or macroscopic abnormalities were observed. The oral LD₅₀ of the test item was greater than the limit dose of 2000 mg/kg bw.

The acute oral toxicity of Resin acids and rosin acids, hydrogenated, potassium salts was evaluated in a study conducted according to OECD Guideline 420 (Eastman Kodak Company, 2005a). Following confirmation that a dose of 300 mg/kg bw administered by gavage to a single female rat was not toxic, five female rats were each administered a single dose of 2000 mg/kg bw of the test substance by gavage. All animals survived to study termination. All animals gained weight normally and there were no signs of systemic toxicity. The acute oral LD₅₀ in this study was >2000 mg/kg bw for female rats. 

In an acute oral toxicity study, a group of five male and five female rats was administered a single dose of Rosin, reaction products with formaldehyde (CAS No. 91081-53-7) by oral gavage at a dose level of 5000 mg/kg bw (Food & Drug Research Laboratories, Inc, 1985a). The rats were observed for mortality and adverse clinical signs for a period of 15 days. One of five males and two of five females were found dead on the morning following dosing (Day 2). A third female was found dead on Day 3. No other mortality was noted for male or female rats during the study. Abnormal clinical signs were reversible and included decreased activity (1/5 males and 1/5 females), diarrhoea (2/5 males and 2/5 females), ataxia (1/5 females), and wet abdomen (2/5 females). No other abnormal clinical signs were evident during the study. All surviving animals of both sexes gained weight over the 15-day observation period. No gross pathological lesions were reported at necropsy. Based on the results of this study, the oral LD₅₀ of Rosin, reaction products with formaldehyde (CAS No. 91081-53-7) is >5000 mg/kg bw in male and female rats.

In another acute oral toxicity study, a group of five male and five female rats was administered a single dose of Rosin, reaction products with formaldehyde (CAS No. 91081-53-7) by oral gavage at a dose level of 1000 mg/kg bw (Food & Drug Research Laboratories, Inc, 1985b). The rats were observed for mortality and adverse clinical signs for a period of 15 days. No mortality was noted during the study. Abnormal clinical signs were limited to diarrhoea for a single male and a single female on the day of dosing and on the morning of the day after dosing. No other abnormal clinical signs were evident during the study. All animals of both sexes gained weight over the 15-day observation period. No gross pathological lesions were reported at necropsy. Based on the results of this study, the oral LD₅₀ of Rosin, reaction products with formaldehyde (CAS No. 91081-53-7) is >1000 mg/kg bw in male and female rats.

 

In an early study that pre-dated the development of GLP and study guidelines, treatment of albino rats and guinea pigs with Wood Rosin (Rosin) at doses ranging from 1 - 5 g/kg (rats) and 1 - 4 g/kg (guinea pigs) resulted in oral LD₅₀ values of 2.8 g/kg in rats and between 1 - 2 g/kg in guinea pigs (Kodak Laboratory of Medicine, 1956).

The acute oral toxicity of Rosin, oligomers was also evaluated in an investigation that pre-dated the development of GLP and study guidelines but which was conducted according to acceptable scientific methodology in effect at the time (Wharf Institute, 1977). In this study, a group of 10 rats/sex/group received a dose of 2500, 5000, 7500 or 10000 mg/kg bw of the test material administered by oral gavage. All animals in the 2500 mg/kg bw dose group survived to study termination while all females and 8 of 10 males in the high-dose group died. In the 5000 mg/kg bw dose group, 2 of 10 males and 3 of 10 females died.  In the 7500 mg/kg bw dose group, 1 of 10 males and 5 of 10 females died. There were no adverse clinical signs observed during the 14-day observation period and all animals surviving to study termination gained weight. Although a gross post mortem examination was performed on all animals, the results of those examinations were not provided in the study report. The oral LD₅₀ for Rosin, oligomers was between 7500 and 10000 mg/kg bw for males, and between 5000 and 10000 mg/kg bw for females.

Acute Dermal Toxicity

In a key acute toxicity study in rats (Bradshaw, J., 2010), agroup of ten animals (5/sex) were given a single, 24 hour, semi-occluded dermal application of fatty acids C18-(unsaturated) lithium salts to intact skin at a dose level of 2000 mg/kg bodyweight. No mortality or signs of systemic toxicity were observed through the study period. Well-defined erythema and very slight oedema were noted at the test site of one animal. There were no signs of dermal irritation noted in the remaining animals. No abnormalities were noted at necropsy. The acute dermal LD₅₀ was determined to be greater than 2000 mg/kg bodyweight.

 

The acute dermal toxicity of Resin acids and rosin acids, hydrogenated, potassium salts was evaluated in a study conducted according to OECD Guideline 402 (Eastman Kodak Company, 2004a). Five rats/sex were administered a single dose of 2000 mg/kg bw Resin acids and rosin acids, hydrogenated, potassium salts under occluded contact for 24 hours and observed for 14 days. All animals survived to study termination. All animals gained weight normally and there were no signs of skin absorption or systemic toxicity. The acute dermal LD₅₀ in this study was >2000 mg/kg bw for male and female rats. 

 

In an acute dermal toxicity study, a group of five male and five female rats was administered a single dose of Gum Rosin (Rosin) topically, under a porous gauze dressing, at a dose level of 2000 mg/kg bw in dimethylsulfoxide vehicle for an exposure period of 24 hours (Phycher Bio Development, 2009). Under the conditions of this study, the dermal LD₅₀ of Gum Rosin in male and female Sprague-Dawley rats was > 2000 mg/kg bw. No mortality was observed in the study and, after a lack of body weight gain was noted in all males and females on Day 2, the animals recovered and gained weight normally over the rest of the study period. No clinical signs related to the administration of the test substance were observed. Other than dryness (mostly slight) noted at the treatment site of one or more animals at various times during the study, there were no signs of irritation, necrosis, ulceration or evidence of tissue destruction reported. At necropsy, no gross lesions were observed. Based on the results of this study, Gum Rosin was not acutely toxic to rats via the dermal route.

 

Acute Inhalation Toxicity

No studies were available for review, however a low vapour pressure indicates that exposure via this route is unlikely. 

Justification for classification or non-classification

Not classified for acute lethality by the oral or dermal routes of exposure under EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008. For non-EU countries, the UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS) defines a fifth category for acute toxicity for chemicals with oral LD₅₀ values between 2000 and 5000 mg/kg/bw. Insufficient data were available to provide a definitive classification under UN GHS. The physico-chemical properties of the category members indicate no requirement for classification with regard of aspiration hazard (kinematic viscosity exceeds 20.5 mm2/s at 40°C).