Disodium 2,2'-([1,1'-biphenyl]-4,4'-diyldivinylene)bis(benzenesulphonate)

Endpoint summary

Description of key information

oral: LD50 > 2000 mg/kg bw, CIBA, 281834, 1990, OECD 401
dermal: LD50 > 2000 mg/kg bw; CIBA, 281845, 1990, OECD 402
inhalation: LC50 = 3.92 mg/L air (4 hour exposition); CIBA, 280980, 1990, OECD 403

Additional information

Oral:

In an acute oral toxicity study (OECD 401, CIBA, 281834), groups of fasted 8 -10 week old rats (5/sex) were given a single oral dose of the test substance in water at 2000 mg/kg bw. and observed for 14 days. No mortality occurred. No clinical signs were observed during the study period. The body weight gain of the animals was not affected by the test article treatment throughout the entire study period. No macroscopically organ findings were observed. This result is supported by further studies also with other species (mice, hamster).

Dermal:

In an acute dermal toxicity study (OECD 402, CIBA, 281845, 1990), groups of 10 - 12 week old rats (5/sex) were dermally exposed to the test substance (diluted in water) for 24 hours to 10% of body surface area at 2000 mg/kg bw. Animals then were observed for 14 days. No mortality occurred and normal body weight gain were found in this study. Males and females showed yellow skin and scales at exposure site. All animals had recovered after 7 observation days. No systemic signs were observed in the animals throughout the entire study period. At autopsy, no deviations from normal morphology were found. This result is supported by two older studies in which rats and rabbits were used (Ciba 1973 b and c).

Inhalation:

In an acute inhalation toxicity study according to OECD Guideline 403 (CIBA, 280980, 1990) groups of young adult Wistar rats (5/sex) were exposed by inhalation route to the test substance (90% a.i.) as aerosol for 4 hours to nose only at concentrations of 1.44, 2.83, or 3.94 mg/L. Animals then were observed for up to 28 days. Deaths did not occur in the low exposure concentration. At the mid dose group one male died on test day 8 (20% mortality) and one female on test day 9 (20%). In the high dose group one male died on test day 2, two others on test day 10 and two females on test day 9. No treatment-related effects were noted in animals of the low dose group concerning the body weight. The mean body weight increase was less in the mid dose group than in the low dose group during the first week of observation. In the high dose group, one surviving male lost weight during the first three weeks of observation whereas the other male gained weight at a normal rate. The average body weight of the three surviving females of this group decreased until the end of the second week of observation and then increased again. No clinical signs were noted during exposure in any dose group. After exposure, hunched posture, labored respiration and rales were noted in one female of the low dose group on test day 3. Sedation, hunched posture, stiff gait, labored respiration, rales and ruffled fur were noted in most animals of the mid dose group. Sedation (one male and one female) and stiff gait were seen only on test day 1 whereas most other signs were observed for more than two weeks. The same signs as well as tachypnea and alopecia (1 female only) were seen in animals of the high dose group. Rales were noted until the end of the third week of observation. Hunched posture, stiff gait, labored respiration and ruffled fur were observed until the end of the 4-week observation period. At necropsy the lungs of all animals of low dose group were incompletely collapsed. In one male, several dark red foci were seen on the left lobe and in another male a dark red focus on the right cranial lobe. The lungs of all animals of mid dose group were incompletely collapsed. A dark red or a reddish discoloration was observed in two cases. One or many dark red foci were noted in two males, and two females. The lungs of animals of the high dose group were incompletely collapsed (9 cases) or not collapsed (1 case). A reddish or dark red discoloration was noted in four animals and many dark red or reddish foci in five animals. As derived from the overall study results the acute LC50 values are:  LC₅₀Males =  3.66  mg/L (95% C.I. 3.44 -3.90),  Females = 4.32 mg/L (95% C.I. 3.82 -4.89), Combined = 3.92 mg/L (95% C.I. 3.61-4.27)

      

Justification for classification or non-classification

Dangerous Substance Directive (67/548/EEC)

The available studies are considered reliable and suitable for classification purposes under 67/548/EEC. As a result the substance is not considered to be classified for acute oral or dermal toxicity under Directive 67/548/EEC, as amended for the 28th time in Directive 2001/59/EC.

For inhalatory toxicity a classification is not considered since the test substance is only available as pellets which contain no breathable particles (2% of test substance have particle size of smaller or equal to 40 µm). During production an abrasion which could lead to a relevant dust exposure is very improbable. Therefore the substance is not considered to be classified for inhalatory toxicity under Directive 67/548/EEC, as amended for the 28th time in Directive 2001/59/EC.

 

Classification, Labelling, and Packaging Regulation (EC) No. 1272/2008

The available experimental test data are reliable and suitable for classification purposes under Regulation 1272/2008. As a result the substance is not considered to be classified for acute oral or dermal toxicity under Regulation (EC) No. 1272/2008.

For inhalatory toxicity a classification is not considered since the test substance is only available as pellets which contain no breathable particles (2% of test substance have particle size of smaller or equal to 40µm. During production an abrasion which could lead to a relevant dust exposure is very improbable. Therefore the substance is not considered to be classified for inhalatory toxicity under Regulation (EC) No. 1272/2008.