One place it is commonly found is in paint. Years ago, lead was used in paint so its very possible you will encounter it in an older home. This will start to become a health concern if it has started to deteriorate as it will chip or turn to dust, which will then spread and settle throughout the home. Children are more likely to be exposed to lead paint dust or chips as they play and run around, making them vulnerable to the effects of lead. If lead paint was used on the exterior of the home you may find that soil in the surrounding area contains lead as well. Lead was also used in pipes year ago which may have an affect on drinking water.
If you live in a modern home, does that mean lead will not be a problem? Not necessarily. If the homes occupants enjoy older furniture there is also a chance that it contains lead or lead based paint. This is another area where children could be exposed so, before purchasing antique items, check to see if there is the possibility that lead was used on it.