It's present in a lot of manufactured timber products - sheet materials especially. It's up to you to assess the hazard. But my own take is that the ventilation of a typical house disperses it sufficiently for me not to worry about it. If your assessment of risk (or your own vulnerability) is different then avoid new sheet manufactured materials - live in an old house with older furniture (formaldehyde out gas takes 19-15 years to disperse). Life is full of hazards of many degrees, it's up to you to judge which are significant to you.