'Sorry to hear this :( please let us know how S.A. Wilsons responds.
A quick google search (on "enema bucket" + plastic) shows that almost every supplier seems to have switched to the blue-tinted tubing (with a different clamp style). Since I'm fairly certain S.A. Wilsons doesn't manufacture the buckets or tubing, it's likely they didn't have any choice in the matter (and just haven't yet changed their image). The image of the bucket in the "bucket hanger", appears to have blue tubing.
(it appears to me that the very slight blue tint is the reflection off the blue tip protector, as the top of the tubing coil is clear).
I just ordered two of these (above), as the clamp on my original S.A.Wilsons bucket broke a few weeks ago (it lasted 3-4 YEARS)...so as soon as I get mine, I'll let everyone know (I'm thinking maybe the small suppliers with a large stockpile still have the originals???)
There's a possibility the "blue" is some type of "sterile coating" and it's supposed to come off - I don't know. If I were you, I'd run straight 3% hydrogen peroxide into the tubing, clamp it (so it stays in the tubing for awhile) and see if you can't get all the 'blue' off the inside of the tubing. And scrub the outside with hydrogen peroxide and a non-toxic soap...and see if you can't get it off. If whatever it is will dissolve in organic coffee or in hot water, you should have no problems removing it.
It seems totally illogical that a medical company would use anything "toxic" on enema tubing, but that's certainly no guarantee that they didn't.
Anal itching? That's usually nothing any type of enema will resolve (unless it's just to bring a bit of temporary comfort). The most common cause of anal itching is pinworms...so you'd need to get on some parasite herbs to take care of that. And always, Always, ALWAYS do a thorough Colon Cleanse WHILE doing parasite herbs...otherwise they'll just bury into the junk in the colon so the herbs won't hit them (and you'll be doing parasite herbs 'forever').