The debate surrounding whether colours can affect our mood, productivity and psychological wellbeing has been argued throughout history. One of the first studies to look into the links between colour and mood was in 1979 by Schauss. It was a

If a house is old enough, it will likely have oil-based paint somewhere, since water-based latex paint wasn't introduced until the 1940s. And newer houses might have some areas of oil-based paint since it is not entirely banned: Oil-based paint