I chose a water-based stain, Minwax Water-Based (https://www.minwax.com/wood-products/stains/minwax-water-based-wood-stain), for my recent unfinished pine shelving project mostly for the lower VOC content. However I was surprised to see formaldehyde on the SDS, especially when you don't often see that on the supposedly more toxic oil-based stuff.
For indoor air quality, does anyone know if this kind of formaldehyde concentration is a concern? Concentration is reported as <0.1% by weight, don't know if that's significant or not. I was hoping to avoid any sort of finish or sealer, not sure if that would help or not.