α,α,α-trichlorotoluene

Endpoint summary

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Additional information

Skin irritation:

Two studies are available on skin irritation of the benzotrichloride. They both are based on animal studies. One is based on an american standard method and the other on a in-house method.

In a study report from Mihail (1978), the authors tested the skin irritation potential of benzotrichloride (CAS n° 98-07-7) on rabbits according to the method described by the Code of Federal Regulations, Title 16, Section 1500.41. Intact and abbraded skin of six New Zealand White rabbits (male/female) were exposed to the test substance for 24h. At the end of exposure (24h) as well as after 72h and 7d, respectively 48h and 6d after ending of exposure, erythema and edema were scored with a system similar to the OECD recommendations. Using the scores obtained for these two parameters, the primary irritation score was calculated which is based on the observations at 24h and 72h.

Under the test conditions, very slight to well-defined erythema and very slight to slight edema was observed at 24h (end of exposure) and 72h (48h after ending exposure) for both intact and abbrated skin. This resulted in a primary irritation score of 2.8 (maximum is 8). Furthermore after 7d the effects of exposure to benzotrichloride were not reversible.

In an other study from Smyth (1951), the authors tested the skin irritation potential of benzotrichloride (CAS n° 98-07-7) according to a methodology described by Smyth and Carpenter [Journal of Industrial Hygiene and Toxicology (1948) 30: 63-68]. The skin of rabbits was exposed to the test substance (no details on the method of application) and afterwards skin irritation was scored according to a system described in Smyth H.F., Carpenter C.P.and Weil C.S. (1949) [Journal of Industrial Hygiene and Toxicology 31: 60-62].

Again, this scoring system is not comparable to the OECD scoring system, and hence no further comparison is possible between both studies.

However, in the test conditions, the primary skin irritation score was 5, meaning that strong erythema, edema or slight necrosis was observed.

Based on the study of Mihail (1978), no strong irritancy potential is described whereas the experiment of Smyth (1951) is more controversial and would strongly suggests a corrosive effect. However, as few details are available on the Smyth experiment, this study was considered as not assignable and not useable for any regulatory purpose. Besides, the study from Mihail was based on a recognized testing method, and hence was chosen as a key study thanks also to its relevancy and reliability.

Eye irritation:

Two studies are available on eye irritation of the benzotrichloride. They both are based on animal studies. On is based on an american standard method and the other on a in-house method.

In the study report from Mihail, the authors tested also the eye irritation potential of benzotrichloride(CAS n° 98 -07 -7) on rabbits according to the method described by the Code of Federal Regulations, Title 16, Section 1500.42). The eyes of six New Zealand White rabbits (male/female) were exposed to 0.1 mL of test substance. After 1h, 24h, 48h, 72 h and 7 days the eyes were examined and the grade of ocular reactions recorded.

Under the test conditions, only two out of the six animals displayed an effect of the test substace in the cornea. In these cases the slight opacity of the cornea was restricted to confined areas after 24h, 48h and 72h. At day 7, effects of treatment with benzotrichloride could no longer be detected in the cornea. In addition, the iris did not show any effects of treatment for all test animals at all time points. Finally, the effects observed for the conjunctivae persisted after 7 days in 5 out of 6 animals, thus these effects were not fully reversible within 7 days. Hence, at this level of information benzotrichloride is considered slightly irritating according to the Code of Federal Federal Regulation.

In an other study from Smyth (1951), the authors tested the eye irritation potential of benzotrichloride (CAS n° 98-07-7) according to a methodology described by Carpenter and Smyth (1946) [American Journal of Ophthalmology 29: 1363-1372]. The eyes of rabbits were exposed to the test substance and afterwards eye irritation was scored according to Carpenter and Smyth (1946). Again, this scoring system is not comparable to the OECD scoring system, and hence no further comparison is possible between both studies.

In these test conditions the eye injury score was 10, but as the scoring system was not given in this study an interpratation is not possible.

Based on the study of Mihail (1978), no strong irritancy potential is described whereas the experiment of Smyth (1951), even if more controversial, would suggests an irritant effect. However, as few details are available on the Smyth experiment, this study was considered as not assignable and not useable for any regulatory purpose. It only gives little support to the experiment of Mihail as also signs of irritation are observed. Besides, the study from Mihail was based on a recognized testing method, and hence was chosen as a key study thanks also to its relevancy and reliability.

Effects on eye irritation: corrosive