; (2) aplastic anemia; (3) paroxysmal nocturnal hemoglobinuria; (4) pure red cell aplasia; (5) acute myeloid leukemia that has progressed from myelodysplastic syndromes; or (6) large granular lymphocytic leukemia. (e) Authorization of appropriations There is authorized to be appropriated to carry out this section $3,000,000 for each of fiscal years 2019 through 2023. . (d) Pilot studies through the agency for toxic substances and disease registry (1) Pilot studies The Secretary of Health and Human Services, acting through the Director of the Agency for Toxic Substances and Disease Registry, shall conduct pilot studies to determine which environmental factors, including exposure to toxins, may cause acquired bone marrow failure diseases. (2) Collaboration with the Radiation Injury Treatment Network In carrying out the directives of this section, the Secretary may collaborate with the Radiation Injury Treatment Network of the C.W. Bill Young Cell Transplantation Program established pursuant to section 379 of the Public Health Service Act ( 42 U.S.C. 274k ) to— (A) augment data for the pilot studies authorized by this section; (B) access technical assistance that may be provided by the Radiation Injury Treatment Network