Which of the following is a risk factor for lead exposure?

Living in urban areas built before 1978 is a significant risk factor for lead exposure due to the historical use of lead-based paints and lead-containing plumbing materials in homes constructed during that time. Many older buildings, particularly those built before the ban on lead-based paints in residential properties, are likely to have lead hazards. This can include deteriorating paint, lead dust, and lead in water from plumbing systems. Individuals residing in these environments may face a heightened risk, especially if there is renovation or remodeling, which can disturb lead-based materials.

On the other hand, newly built homes typically adhere to current safety standards and regulations that prohibit the use of lead-based materials. Household pets do not inherently increase the risk of lead exposure, as their presence does not directly relate to the presence of lead hazards. Additionally, using bottled water exclusively is not a risk factor; rather, it can sometimes be a safer alternative if there are concerns about lead in tap water from plumbing systems. Thus, living in older urban areas remains the primary concern for potential lead exposure.