Excess bilirubin is not uncommon in babies of this age and I belive it is a normal physiological resonse. Is baby jaundiced at all?
My son recieved treatment for this as he was severly jaundiced (birth trauma - ventouse and forceps). He had UV light therapy and on of the side effects is loose greenish poo.
If the baby is getting a lot of sunshine at the momnet it may be that this is the cause. My childminder calls it summer poo
It is important to keep breastfeeding. If it is the sunshine it may stop when there is less.
One thing which I found irritated my son both before and after he was born were onions and leeks, gave him colic after birth and me hearburn before, another thing which irritated was sweet pepper.
If it is lose poo, it may be scouring the child around the anus and making it uncomfortable. Try to keep lots of fresh air on it if possible ie nappyless.
Janyce