α,α,α,4-tetrachlorotoluene

Endpoint summary

Description of key information

Acute oral toxicity

LD50 = 572 mg/ kg bw/ day for both sexes

Acute inhalation toxicity

LC50 (4 hour) = 1.43 g/m3 (corresponding to 1.43 mg/l) of air

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

572 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LC50

Value:

1 430 mg/m³

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Acute oral toxicity

For the acute oral toxicity, three studies are reported in this dataset. They are all based on the acute standard testing method (OECD guideline 401 or similar).

In the key study, Sprague Dawley rats (5 males/dose) received a single oral administration of the test article PCBTC at the doses of 547, 820 and 1230 mg/kg. In order to confirm the obtained data, further groups of 5 females were administered 547 and 365 mg/kg of test article.

The test method was in accordance with OECD Guideline n. 401. The test article was administered undiluted at the volumes of 0.24, 0.37, 0.85 and 0.82 ml/kg in order to give the above mentioned doses (being the density 1.495 g/mL).

All rats were treated after a 16 hours fasting period. The day of treatment was considered day 1 of the study. The animals were weighed twice before treatment and on days 3, 8 and 14. They were clinically observed for 14 days after treatment and on day 15 they were killed by excision of the femoral arteries. Animals which died and animals killed at the end of the study were submitted to a thorough autopsy.One male treated at 820 mg/kg and all treated at 1230 mg/kg died within 24-48 hours of the test article administration. All females treated at 547 mg/kg died within 24-48 hours of the treatment. No males treated at 547 mg/kg and no females treated at 365 mg/kg died. Females appeared to be mnore sensitive than males. Only piloerection and hunched posture were clinically observed in females treated at the lowest dose strating from 2 hours and lasting up to days 2-3 of the study. Animals treated at the other doses showed sedation or hypoactivity, piloerection, hunched posture, hypothermia and salivation starting from 30 minutes-4 hours and lasting up to 6 hours - day 9 of the study. midryasis was also observed during the first hours after treatment in animals which died. Sporadic cases of reddish nasal discharge, chromodacryorrhea, staggering and lacrimation were also noted in these animals during the first day of the study. Recovery of all surviving rats was achieved within days 4 -10 of the study. Decrease in body weight or low body weight gain was noted in almost all animals at the day 3 weighing and in some animals also at the day 8 weighing. Body weight gain returned to normal at the subsequent weighings.

At the autopsy, animals which died showed changes in the lungs (congestion and edema), in the liver (paleness in only one female treated at 547 mg/kg), in the kidneys (congestion in only one male treated at 1230 mg/kg), in the stomach (congestion and thinning walls), in the intestine (thinning walls and catarrhal content in only one male treated at 1230 mg/kg) and in the spleen (paleness and decreased size). At the gross pathology examination performed at the end of the observation period thickened of the stomach walls with presence of mucus and sporadic cases of erosions of the gastric mucosa were observed.

In cocnlcusio, under test condition the LD50 value was found to be 572 mg/kg bw.

In the first supporting study (Hoechst AG, 1984), the authors tested the acute oral toxicity of 4-chloro-benzotrichloride (CAS n° 5216-25-1) according to the OECD guideline 401. They administered one oral dose ranging from 315 mg/kg bw to 800 mg/kg bw with a gastric probe to five wistar rats at each dose (both sexes) . They followed the mortality, performed clinical examinations and gross pathology on dead rats (surviving rats killed) over an observation period of fourteen days.

At the end of the experiment, the authors estimated by probit analysis a LD50 of 652 mg/kg bw for male rats and a LD50 of 581 mg/kg bw for female rats. The mortality was correlated with well documented clinical and gross pathology observations (e.g: breathing disruption, signs of anxiety...). After statistical analysis, the authors concluded that the LD50 for wistar rats in the test conditions was estimated at 614 mg/kg bw. This value is in line with the one obtained in the key study.

In the second supporting study (Bayer AG, 1980), 4 -chloro-benzotrichloride was tested only on male Wistar rats. The study is less documented but still gives sufficient information to be considered as reliable. Furthermore, the authors found in this study a LD 50 around 690 mg/ kg bw/day. Also this value is in line with the previous reported information and gives good support to the key study.

Acute Inhalation toxicity

The acute inhalation toxicity of 4 -chlorobenzotrichloride was assessed by exposing 3 groups of rats for a period of 4 hours, to atmospheres containing a respirable aerosol of the test substance (whole body method), following a procedure similar to the OECD guideline 401. The study was performed with albino rats CD strain (SpragueDawley), females and males. One control group exposed to clean air was used too.

At the atmosphere concentartions of 0.99, 1.31 and 2.32 g/m3 of chamber air, the calculated LC50 resulted to be established at 1.48 g/m3 of air. Acute exposure to the aerosol, at the concentrations used for this study, produced irritation to the eyes and skin of the rat and had a marked injurious effect on the lungs and upper airways.

Justification for classification or non-classification

According to the criteria of the CLP regulation n° 1272/2008, the the test substance should be considered as:

- toxic after single oral administration, Category 4 since the LD50 for rats is between 300 and 2000 mg/kg bw.

- toxic after single exposure via inhalation route Category 4, since the LD50 for rats is between 1 and 5 mg/l (threshold for dust and mist).