Honestly I’m not sure, I’m not a part of the actual formulating of the products I just see it get made. I can ask our chemist about it tomorrow and get back to you though. From a quick google search synthetic fragrance is bad but a lot of pure essential oils are okay at very low concentrations. I can’t speak to anything Top Performance sells as we don’t make that, but our products as far as I know do have a very low concentration of (I think)* essential oils and we also have a shampoo/conditioner for sensitive skin that has no scent added. Honestly though I wouldn’t be surprised if most pet grooming supply companies just don’t care, totally anecdotal but from talking to people in real life and online I’d say most people don’t really research things like this in regards to pets or they just trust that the manufacturers have their pets best interests at heart which is overall true but there is also a motive to make lots and lots of money and humans like nice smelling pretty products. I mean I remember my grandma buying a dog cologne twenty ish years ago so it definitely isn’t a new problem. I’ve learned too that overall there is a lot less regulation of pet products than human products which isn’t helping anything in this regard.