Tell your husband that any time there is a plumbing problem, there is always a potential health problem associated with that.
Sounds like a partial backup in your system that needs to be removed.
The bubbling is caused by air displacement through the drain when water rushes towards the obstruction in the line.
Liquid drain cleaners are a waste of time, rodding the drain with a electric drain cleaning machine from a rental yard is your best defense in addressing this matter.
“Your best interest is secured by making the right decisions the first time.”