Registration Dossier

Administrative data

Description of key information

In OECD guideline studies, slight skin and slight eye irritation were reported in rabbits exposed to undiluted C14-17 chlorinated paraffins (40 and 52% chlorination, containing 1% epoxy stabiliser). Slight skin irritation was also reported in additional unpublished studies in rabbits and rats. There are no data specifically in relation to respiratory tract irritation, but on the basis of the low skin and eye irritation potential and generally unreactive nature, and the lack of human reports, it is anticipated that MCCPs are unlikely to cause such an effect.

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (irritating)

Eye irritation

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Additional information

No data are available in humans relating to skin or eye irritation, and no data in relation to respiratory irritation in humans or animals.

 

Only slight skin irritation (mean 24-72 h scores for erythema and oedema were 1.5 and 0.6, and 1.3 and 0.3, respectively) was reported in two studies (Kuhnert, 1986c,d) conducted according to OECD Guideline 404, in which rabbits were exposed for 4 h (occluded) to undiluted C14-17 chlorinated paraffins (40 and 52% chlorination respectively, containing 1% epoxy stabiliser). Scales were also seen from the 6th to 10th day following exposure, and in the case of the first study, drying and hardness (at 72 h) and “peeling” (observed on days 6-8) presumably of the outermost layers of the skin was seen. In briefly reported unpublished studies in rabbits and rats (Birtley et al. 1980; Chater, 1978; Moses, 1980), desquamation and/or slight irritation were noted after single and/or repeated skin application of C14-17 chlorinated paraffins (40-60% chlorination, containing 0.2% stabiliser). Overall, all of these studies, although having some limitations in reporting, are consistent and indicate that MCCPs have only slight skin irritation potential. In one of the studies (Chater, 1978), a poorly reported study which does not meet current guidelines, some cracking of the skin was seen (probably because of defatting) in two out of three rats following six skin applications (over 12 days) of undiluted Meflex DC024 or DC029 (C14-17 chlorinated paraffins; 40 and 45% chlorinated, respectively). However, skin cracking was not reported in a number of other in vivo skin irritation studies involving repeated dermal application of C14 -17 chlorinated paraffins (Birtley et al. 1980; Moses, 1980).

 

Two guideline studies (OECD 405) indicate that undiluted C14-17 chlorinated paraffins (40 and 52% chlorination respectively, containing 1% epoxy stabiliser) produce only slight eye irritation when instilled into the conjunctival sac of each of 3 rabbits (Kuhnert, 1986e,f). "Slight transient conjunctivitis" was seen shortly after C14-17 chlorinated paraffins (40 and 45% chlorination, containing 0.2% epoxy stabiliser) were instilled into the conjunctival sac of each of 3 rabbits (Chater, 1978). No irritation was noted in briefly reported unpublished studies (Birtley et al. 1980), involving a single application of different types of C14 -17 chlorinated paraffins (51-60% chlorination) into the eyes of rabbits.

 

There are no data specifically in relation to respiratory tract irritation. However, the lack of any reports relating to this endpoint given the widespread use of these substances, suggests that they lack the potential to cause such an effect. The low skin and eye irritation potential and generally unreactive nature of this group of substances lends further support to this view.

Although there is only limited information the degree of chlorination does not appear to be of significance for these endpoints.


Effects on skin irritation/corrosion: slightly irritating

Effects on eye irritation: slightly irritating

Justification for classification or non-classification

Based on the slight, reversible, skin irritation seen in rats and rabbits, and the slight eye irritation seen in rabbits exposed to the undiluted material, MCCPs would not be classified as skin or eye irritants according to the EU CLP or DSD regulations. In a poorly reported study (which does not meet current standards), some potential for cracking of the skin was noted following repeated dermal application of an undiluted liquid MCCP to rats, probably via a defatting mechanism. However, such an effect was not seen in a number of other repeated dermal studies with undiluted MCCPs in rats, and no reports of skin cracking in humans has been reported. Therefore, MCCPs would not be classified as 'repeated exposure may cause skin dryness or cracking’.