The CDC “level of concern” (10 µg/dL) has been updated in the CDPH exam to reflect the CDC “reference level” (currently 5 µg/dL) for lead in children’s blood. Although the BLL change and “reference level” had been changed several years ago, we are now seeing the update in the State of CA LRC exams. This is great news to be able to share that the State of CA LRC exam is now matching what is taught.

Feel free to share this information with your employees, associates or colleagues to help support the industry and anyone taking the exam.

Excerpt from CDPH:

“This electronic alert is to inform you that all questions on the California Department of Public Health Lead Related Construction exams regarding the CDC “level of concern” (10 µg/dL) have been updated to reflect the CDC “reference level” (currently 5 µg/dL) for lead in children’s blood…this update will be in place for students taking the September 2019 CDPH LRC exams onwards…This minor change to the CDPH LRC exams was achieved utilizing the current resources of the program. Major revision of the exams would require significantly more resources than currently available.”



Blood Lead Levels in Children

Protecting children from exposure to lead is important to lifelong good health. No safe blood lead level in children has been identified. Even low levels of lead in blood have been shown to affect IQ, ability to pay attention, and academic achievement. And effects of lead exposure cannot be corrected.

The most important step parents, doctors, and others can take is to prevent lead exposure before it occurs.


  • In 2012, CDC updated its recommendations on children’s blood lead levels.
  • By shifting our focus to primary prevention of lead exposure, we can reduce or eliminate dangerous lead sources in children’s environments BEFORE they are exposed.
  • What has not changed is the recommendation for when to use medical treatment for children. Experts recommend chelation therapy when a child is found with a test result of greater than or equal to 45 micrograms per deciliter of lead in blood.
  • Though lead can be found in many sources, lead exposure is entirely preventable. The key is stopping children from coming into contact with lead and treating children who have been poisoned by lead. Parents can take simple steps to make their homes more lead-safe.
  • Children can be given a blood test to measure the level of lead in their blood. Talk to your child’s doctor if you are concerned about lead exposure.


CDC Blood Lead Reference Value (BLRV)

  • CDC now uses a blood lead reference value of 5 micrograms per deciliter to identify children with blood lead levels that are much higher than most children’s levels. This new level is based on the U.S. population of children ages 1-5 years who are in the highest 2.5% of children when tested for lead in their blood.
  • This reference value is based on the 97.5th percentile of the National Health and Nutrition Examination Survey (NHANES)’s blood lead distribution in children. The current reference value is based on NHANES data from 2007-2008 and 2009-2010.
  • Every four years, CDC will review the most recent two sets of NHANES data to find the 97.5th percentile of blood lead distribution in children.
  • NHANES is a population-based survey to assess the health and nutritional status of adults and children in the United States and determine the prevalence of major diseases and risk factors for diseases.


Previous Terminology

  • Until 2012, children were identified as having a blood lead “level of concern” if the test result is 10 or more micrograms per deciliter of lead in blood. CDC is no longer using the term “level of concern” and is instead using the reference value to identify children who have been exposed to lead and who require case management.
  • In the past, blood lead level tests below 10 micrograms per deciliter of lead in blood may, or may not, have been reported to parents. The new lower value means that more children will likely be identified as having lead exposure allowing parents, doctors, public health officials, and communities to take action earlier to reduce the child’s future exposure to lead.