GameObject Instanitation causing lag on webgl for mac os with chrome

I have a game where items drop from the sky and land on a table in a pile. You can pick up and place the items. When the items get instantiated they appear one at a time over the period of a second (so not all in one frame). This works great on all browsers (60 fps) except Chrome on Mac OS (3 fps). I don't really know where to start with this sort of browser specific thing. We've had issues with this browser before with other games but never as bad as this. Any help/suggestions would be useful!