Tetrahydrothiopyran-3-carboxaldehyde

Endpoint summary

Description of key information

Acute Oral toxicity
Rat: 	LD50 (f): 3120 mg/kg, 	
Rat:	LD50 (m/f): 4520 mg/kg 		(OECD 401, BASF AG 1984)
  	
Acute Inhalation toxicity
Rat: 	LC0: 0.64 mg/l			(OECD 403, BASF AG  1986)
Acute Dermal toxicity
Rat:	LD50 (m/f): >2000 mg/kg 	(OECD 402, BASF AG 1991)

Additional information

Acute Oral toxicity

The acute oral toxicity of the test substance was investigated in groups of 5 male and 5 female rats, given doses of 5000, 3830, 2610, 1780, 1210 mg/kg bw pure test substance as gavage. 1 out of 5 males and 5 out 5 females in the highest dosing group, 3 out of 5 females in the 3830 mg/kg dose group and 2 out of 5 females of the 2610 mg/kg dose group died within the first two days after test substance administration. Signs of toxicity included dyspnoea, staggering, apathy, piloerection, exsiccosis, diarrhea, blood in urine, poor general state in the male animals and dyspnoea, staggering, abnormal position, atony, apathy, piloerection, paresis, pain reflex absent, corneal reflex absent, narcotic-like state, exsiccosis, diarrhea, blood in urine, poor general state in the female animals. All clinical signs returned to normal within 2 days in the surviving animals. At necropsy questionable bloody ulcerations in the urinary bladder were observed in one female of the highest dosing group, other findings mainly comprised the forestomach (intensified focal thickening or slight thickening of the wall). In one case histopathology of the kidneys revealed tubulonephrosis and hyperemia. No macroscopic abnormalities were observed in other organs. Based on the gender-specific mortalities observed, the calculated LD50 differ when including males, females or both sexes into calculations.

 

Acute Inhalation toxicity

The acute inhalation toxicity was investigated in two independent studies in male and female Wistar rats. In the first study 3 male and 3 female rats were exposed for 7 hours to vapours of 0.64 g/l air (mean value calculated over the whole exposure period). In the second study distillation residues of the test substance were investigated at a nominal vapour concentration of 0.11 mg/l air under the same test conditions. No deaths occurred in both studies. In rats exposed to the purified test substance clinical signs of toxicity included muzzling, attempts to escape, irregular respiration and lacrimation during the exposure period, while rats inhaling the residues only showed muzzling and elevated respiration. After the exposure all animals were free on symptoms. At necropsy nothing abnormal was detected. Based on these findings the LC50 was defined as greater than 0.64 mg/l air for a total exposure time of 7 hours.   

 

Acute Dermal toxicity

The acute dermal toxicity was investigated in a limit test in groups of 5 male and 5 female rats in vivo. The test substance was applied for 24 hours to the skin of the back of the animals under semiocclusive conditions. Skin findings were scored 30 - 60 minutes after removal of the semiocclusive dressing and then about one week later and before termination of the study. No deaths occurred. Systemic signs of toxicity were not observed, skin findings included slight erythema and edema on day 1 of application. At necropsy nothing abnormal was detected. Based on these findings the LD50 was defined as greater than 2000 mg/kg after dermal exposure.

Justification for classification or non-classification

Acute Oral toxicity

Since the LD50 values greatly differ between male and female animals, the LD50 value of the more sensitive female animals is used for classification. Based on the criteria defined by the EU system the test substance is not classified and labelling therefore is not necessary. Based on the criteria defined by the GHS system, the test substance is classified to category 5 due to the deaths occurred at the 5000 mg/kg dose level. 

Acute Inhalation toxicity

The present studies discussed above are not sufficient to classify the test substance according to the criteria defined by the EU and the GHS system. Based on the test results there are no indications of enhanced toxicity of the test substance via inhalation, but the test substance was not tested up to the limit concentrations defined by the EU and the GHS system (5 mg/l air). Therefore an appropriate classification of the test substance is not possible.

 

Acute Dermal toxicity

Based on the criteria defined by the EU and the GHS system, the test substance is considered of being not toxic via the dermal route and therefore is not classified.