Sodium N-chlorobenzenesulphonamide

Carcinogenicity

Description of key information

No carcinogenicity studies are planned to be performed.

Key value for chemical safety assessment

Carcinogenicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no study available

Carcinogenicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Carcinogenicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Chloramine B trihydrate does not need to be classified for carcinogenicity according to the Directive 67/548/EEC, Annex VI and CLP regulation (No. 1272/2008 of 16 December 2008).

Additional information

No genotoxic potential for humans was found in the genotoxicity studies with Chloramine B trihydrate, including in vitro bacterial reverse mutation, chromosome aberration and in vivo micronucleus testing, nor in read across data from Chloramine T Micronucleus test, and neither in a mammalian gene mutation test with Benzenesulfonamide. Therefore, genotoxic carcinogenicity can be excluded.

On the other hand, there were no indications for non-genotoxic carcinogenicity based on the suchchronic and chronic toxicity testing. Chloramine B trihydrate when tested in a 90 -day oral gavage toxicity study at dose levels 20, 60, 180 mg/kg bw/day, showed LOAEL (Lowest Observed Adverse Effect Level) for males and females as 60 mg/kg bw/day and NOAEL (No Observed Adverse Effect Level) for males and females at 20 mg/kg bw/day. The liver was considered as a target organ based on irreversible increase in serum bilirubin in high dosed females, significant increases in liver weights (not reversible) and changes of liver colour (reversible) at (mid and) high dosed male and female rats. These changes were without associated histological findings, therefore they might be adaptive rather than toxicological and certainly do not represent any preneoplastic changes. The kidneys were also target organs based on histological findings, although hyaline droplets in renal tubules of mid and high dosed males are not relevant for humans. There was however ‘mesangial cell proliferation’ in the renal glomeruli at 180 mg/kg. Proliferative lesions associated with the renal corpuscle involve Bowman´s capsule, the mesangium and the juxtaglomerular body. None of these lesions has been associated with neoplasia in the rat. (Hard, G.C., Alden, C.L., Stula, E.F., Trump, B.F., 1995, Proliferative Lesions of the Kidney in Rats, In: Guides for Toxicologic Pathology, STP/ARP/AFIP, Washington, DC). These lesions may be immune mediated, infectious, toxic, mechanical, or of other etiologies. A prominent histological feature of many experimental glomerular inflammatory diseases is cellular hyperplasia in the mesangium (proliferation of mesangial cells and an influx of leucocytes (H. O. Schöcklmann, S. Lang, R. B. Sterzel, Regulation of mesangial cell proliferation, In: Kidney International, Vol. 56, 1999, pp. 1199-1207). According to the International Harmonization of Rat Nomenclature „mesangial hyperplasia“ belongs to non-preneoplastic proliferative lesions. (The international harmonized nomenclature is the reset of discussions among the Rat Nomenclature Reconciliation Subcommittee, a presentation during the 1999 Annual STP Meeting in Washington, D.C., and comments which have been sent to the committee up to December 1999. The drafts were based on the STP, WHO/IARC/RITA and NACAD nomenclature systems and were present for discussion in the Internet since Spring 1999.) 

Finally there were no structure activity relationships for genotoxic and non-genotoxic carcinogenicity when tested with the public Toxtree (Q)SAR tool for structure activity relationship. Toxtree is a validated system containing a rule-based system for alerts based on an extensive databases according to Benigni-Bossa. Toxtree was applied to both Chloramine B and T as major test substances and to Benzenesulfonamide and p-Toluenesolfonamide (and o-Toluenesulfonamide) as major metabolites (and comparators). They were all found negative for alerts, therefore they were predicted negative for carcinogenicity.