external soil pipe breather problem.

[S600PJF]

hi
newbie here.
i am not a plumber but am seeking some advice, my soil pipe breather pipe outlet at roof height and mounted outside is showing some strange signs.
there is a blue streak showing running from top to bottom, the paint is also peeling particularly around the top 6 inches or so.
we have not noticed any strange smells but is it possible for sewer gas to back feed and come out and condense and then run down the outside.
i have checked my drain near the road and the rodding bung is removed this giving access to the sewer and bypassing the water u trap.
i took this out several years ago as the outlook blocks occasionally and the rodding eye gives an overflow relief if this happens.
can i have some opinions please ?
regards
pete

 

[oldplumber]

no to streaking, probably from your paint, best to put your rodding eye back, its there to keep rats etc out!!!!!!!!!!!!!!!!!

 

[S600PJF]

thanks for info ref rats.
i see no answer to what this sudden appearance of the bright blue line running down the pipe and the paint peeling off , any one out there seen this before ~?
the outlet to the atmoshere is about 50 feet from the road.
the soil pipe runs into a drain coming from the down stairs toilet.
regards
pete

 

[oldplumber]

if your peeling off pants then the dyes run