The CD symbol is to be used in the CD-version only. Contact me if you want the CD version. One in 11 children in USA has dangerous levels of lead in their blood even if they might not even appear to be sick. Unfortunately, most children with lead poisoning are not overtly symptomatic. It is not only yellow paint that contains lead even if it might be more common in yellow paint.
Some petrol still contains lead.
Old copper pots and pans. Incineration of human waste. Some painted areas are more exposed to wear and tear like Windows and window sills, doors and door frames, stairs, railings and banisters, porches and fences. Dust from paint and soil enter into the air after vacuuming, sweeping, when people walk through it or when using strong fans. Lead glazed pottery or porcelain, or food stored in such items.