A review of the evidence to support interim reference level for dietary lead exposure in adults

Regul Toxicol Pharmacol. 2020 Mar:111:104579. doi: 10.1016/j.yrtph.2020.104579. Epub 2020 Jan 13.

Abstract

FDA developed the interim reference level (IRL) for lead of 3 μg/day in children and 12.5 μg/day in women of childbearing age (WOCBA) to better protect the fetus from lead toxicity. These IRLs correspond to a blood lead level (BLL) of 0.5 μg/dL in both populations. The current investigation was performed to determine if the IRL for WOCBA should apply to the general population of adults. A literature review of epidemiological studies was conducted to determine whether a BLL of 0.5 μg/dL is associated with adverse effects in adults. Some studies reported adverse effects over a wide range of BLLs that included 0.5 μg/dL adding uncertainty to conclusions about effects at 0.5 μg/dL; however, no studies clearly identified this BLL as an adverse effect level. Results also showed that the previously developed PTTDI for adults of 75 μg/day lead may not be health protective, supporting use of a lower reference value for lead toxicity in this population group. Use of the 12.5 μg/day IRL as a benchmark for dietary lead intake is one way FDA will ensure that dietary lead intake in adults is reduced.

Keywords: Adult; Adverse; Blood; Food; IRL; Interim reference level; Lead; Pb.

Publication types

  • Review

MeSH terms

  • Adult
  • Dietary Exposure / adverse effects*
  • Dietary Exposure / standards*
  • Environmental Pollutants
  • Humans
  • Lead / administration & dosage*
  • Lead / adverse effects*
  • Lead / blood

Substances

  • Environmental Pollutants
  • Lead