If someone's worried about liquid seeping through the seems of a hardwood floor... I would re-think what type of floor covering is suitable to install in that area.. If there's enough liquid to penetrate the joints of a hardwood floor...that's excessive liquid on a wood floor. It's going to affect the finish, open the grain, and start delamination. But hey...the joints may be protected
Gluing the joints of a laminate floor would suit a whole different purpose, since the melamine surface is impervious.