Integrated Science Assessment for Lead

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice of availability.

SUMMARY:

The Environmental Protection Agency (EPA) is announcing the availability of a final document titled, “Integrated Science Assessment for Lead” (EPA/600/R–23/375). The document was prepared by the Center for Public Health and Environmental Assessment (CPHEA) within EPA's Office of Research and Development (ORD) as part of the review of the primary (health-based) and secondary (welfare-based) lead national ambient air quality standards (NAAQS) and represents an update of the 2013 Integrated Science Assessment (ISA) for Lead (EPA/600/R–10/075F). The final lead ISA, in conjunction with additional technical and policy assessments, will provide the scientific foundation for EPA's decisions on the adequacy of the current lead NAAQS and, if appropriate, on potential alternative standards.

DATES:

The document will be available on or about January 31, 2024.

ADDRESSES:

The “Integrated Science Assessment for Lead” will be available primarily via the internet on EPA's Integrated Science Assessment Lead page at https://www.epa.gov/isa/integrated-science-assessment-isa-lead or the public docket at http://www.regulations.gov, Docket ID: No. EPA–HQ–ORD–2020–0701; FRL–11654–01–ORD.

FOR FURTHER INFORMATION CONTACT:

For technical information, contact Evan Coffman (919–541–0567 or Coffman.Evan@epa.gov) or Meredith Lassiter (919–541–3200 or Lassiter.Meredith@epa.gov).

SUPPLEMENTARY INFORMATION:

I. Information About the Document

Section 108(a) of the Clean Air Act (the Act) directs the EPA Administrator to identify and list certain air pollutants that “may reasonably be anticipated to endanger public health or welfare” and “the presence of which in the ambient air results from numerous or diverse mobile or stationary sources.” The Act further directs the Administrator to issue air quality criteria for these pollutants. The air quality criteria are to “accurately reflect the latest scientific knowledge useful in indicating the kind and extent of all identifiable effects on public health or welfare which may be expected from the presence of such pollutant in the ambient air . . .” Under section 109 of the Act, EPA is then to establish NAAQS for each pollutant for which the Agency has issued air quality criteria. Section 109(d)(1) requires periodic review and, if appropriate, revision of air quality criteria and the NAAQS to reflect advances in scientific knowledge on the effects of the pollutant on public health or welfare. Information on EPA's process for reviewing the air quality criteria and the NAAQS is available at https://www.epa.gov/naaqs.

EPA has established NAAQS for six criteria pollutants. Presently, the EPA is reviewing the air quality criteria and NAAQS for lead. As part of that review, EPA prepared an ISA that reflects the latest scientific knowledge on the public health and welfare effects of lead exposures, per section 108(a) of the Act. The final lead ISA, in conjunction with additional technical and policy assessments, will provide the scientific foundation for EPA's decisions on the adequacy of the current lead NAAQS and, if appropriate, on potential alternative standards. The Clean Air Scientific Advisory Committee (CASAC), an independent scientific advisory committee with review and advisory functions that are mandated by section 109(d)(2) of the Act, provides independent scientific review of the draft ISA and related draft technical and policy assessments.

On July 7, 2020 (85 FR 40641), EPA formally initiated its current review of the air quality criteria for the health and welfare effects of lead and the primary (health-based) and secondary (welfare-based) NAAQS, requesting the submission of scientific and policy-relevant information on specified topics. This information was incorporated into Volume 2 of EPA's “Integrated Review Plan for the Review of the Lead National Ambient Air Quality Standards (External Review Draft),” which was available for public comment (87 FR 13732, March 10, 2022) and discussed by the CASAC via a publicly accessible teleconference consultation (87 FR 15985, March 21, 2022). Volume 2 of the “Integrated Review Plan for the Review of the Lead National Ambient Air Quality Standards” is focused on planning for the review and the ISA and was posted to the EPA website in March 2022 ( https://www.epa.gov/naaqs/lead-pb-standards-planning-documents-current-review ).

In developing the lead ISA, webinar workshops were held on May 26, June 7, June 22, and June 29, 2022, to discuss initial draft materials with invited EPA and external scientific experts (87 FR 27147, May 6, 2022). The input received during these webinar workshops aided in developing the “Integrated Science Assessment for Lead (External Review Draft)”, released on March 31, 2023 (EPA/600/R–23/061, 88 FR 19302), and made available at: https://cfpub.epa.gov/ncea/isa/recordisplay.cfm?deid=357282. The CASAC met at a public meeting on June 13 and June 14, 2023 (88 FR 17218, March 22, 2023), to review the draft lead ISA. A public teleconference was then held on August 23 and August 24, 2023, for CASAC to review their draft letter to the Administrator on the draft lead ISA (88 FR 45415, July 17, 2023). Subsequently, on September 18, 2023, the CASAC provided a consensus letter of their review to the EPA Administrator (EPA–CASAC–23–003), available at: https://casac.epa.gov/ords/sab/r/sab_apex/casac/activity?p18_id=2637&clear=18&session=363677211680#report. The letter from the CASAC, as well as public comments received on the draft lead ISA, can also be found in the Docket (EPA–HQ–ORD–2020–0701).

The EPA Administrator responded to the CASAC's letter on the draft lead ISA on October 30, 2023, and the letter is available at: https://casac.epa.gov/ords/sab/r/sab_apex/casac/ar?session=8387849145801. EPA has considered comments by the CASAC panel and by the public in preparing this final ISA. More information can be found in Appendix 12, Section 12.7.5, of the final lead ISA (EPA/600/R–23/375).