The "Time-Sensitive Research Opportunities in Environmental Health Sciences (R21 Clinical Trials Not Allowed)" grant from the National Institute of Environmental Health Sciences (NIEHS) supports urgent environmental health research linked to unexpected events or policy changes. The goal is to collect critical data on human biological samples and environmental exposures during a limited window following a natural disaster, human-made crisis, or rapid policy shift. The aim is to understand exposure-health outcome relationships to inform public health actions. This program accelerates the funding process, with awards issued within 4–6 months of application submission.

Eligible projects should address unforeseen events requiring rapid response. Examples include assessing health impacts following disasters, analyzing exposures using novel technologies, or evaluating mitigation strategies. Projects must demonstrate clear scientific value, feasibility within the timeline, and immediate implementation capacity. Non-responsive applications include those focusing solely on animals as exposure surrogates, environmental hazards without health impact, or extending existing studies.

The program anticipates funding 4–5 projects in 2025 with a budget of $800,000. Each award supports projects lasting up to two years, with budgets reflecting project needs. Applications must comply with NIH guidelines and provide detailed plans for addressing human subjects' protections, resource sharing, and data management. Innovative methodologies and partnerships with affected communities or organizations are encouraged.

Eligible applicants include higher education institutions, nonprofits, for-profit organizations, local governments, tribal governments, and foreign organizations. Applications must be submitted electronically through Grants.gov or related systems. A letter of intent, while optional, helps NIEHS gauge the submission scope and potential impact.

Applications will be reviewed based on significance, innovation, rigor, feasibility, investigator expertise, and resource availability. Protections for human subjects and the inclusion of diverse populations will also be assessed. Successful projects should demonstrate high scientific merit, rapid response capability, and potential to address critical public health needs.

The submission deadlines for 2025 start in February, with applications accepted every two months until December 1, 2025. Applicants are encouraged to prepare early to resolve submission issues. Contact information for programmatic, peer review, and grants management inquiries is provided for guidance throughout the application process.