I'm not sure if this has been asked before here.
My case is that I was planning to buy a certain supplement product through iHerb.com. The problem is that the product is not certified as Halal or even Kosher, but yet it is labeled as vegetarian. My concern is that I wanted to make sure whether the product contains any ingredients that is derived from pig /swine. I know for certain that I myself don't possess any means to verify that by myself. But I don't see any ingredient in the ingredient list that, to the best of my knowledge (though I must admit I really don't have any expertise in this field), that hints to it being derived from pig /swine.
Now if I were to ask to the manufacturer of this product, then they testify and even insist that this product doesn't have anything that is derived from any animal (since they have labeled it as vegetarian). According to Islamic Rules would I be sinning if I were to eat from that supplement? Even if it does actually contains something derived from pig/swine but without me knowing anything about it. Will I still be considered sinning?