What common source for lead exposure has been identified in recent years?

The selection of "all of the above" encompasses the various significant sources of lead exposure that have been identified in recent years. Lead pipes are a notable concern, especially in older homes and cities where the plumbing infrastructure may still contain lead materials, leading to contamination of drinking water.

Imported toys have also garnered attention due to instances of lead paint or lead-containing materials being used in their manufacturing, posing risks to children who might put these toys in their mouths.

Home renovations can disturb lead-based paints, which are prevalent in homes built before the 1978 ban on lead in residential paint. When these renovations are undertaken without proper safety measures, they can release lead dust and chips into the environment, increasing the risk of exposure.

By recognizing that each of these sources contributes to lead exposure, it is evident that addressing the lead hazard within multiple contexts is critical for public health, making the answer "all of the above" the most comprehensive choice.