Partner swearing at son??!!

What are everyone's thoughts on swearing at a baby. I've pulled my boyfriend up on it multiple times. Our 1 year old son could be throwing a tantrum, screaming crying and chucking himself around and if my partner has him he doesn't handle it well at all and has at times sworn at him, something along the lines of " what the fuck is wrong with you" or " what the fuck do you want" obviously thinking out loud but when I pull him up on it he will apologise and say he didn't mean it like that.. We swear a lot in general but I've never sworn directly at our son like he does, I swear in adult conversations etc.. I've spoken to him about it and nothing's changed. He is a good father otherwise but this seems to be an issue ATM.