In silico predictions of chemical bioaccumulation in fish provide a valuable alternative to traditional
in vivo bioaccumulation testing (OECD 305). These models are strengthened when supported by
in vitro data on intrinsic clearance, as described in the OECD 319 guidelines.
Smithers delivers both OECD 319A and OECD 319B assays, providing reliable data to inform bioaccumulation potential and support regulatory submissions.
OECD 319 Guidelines:
In Vitro Intrinsic Clearance
The OECD 319 guidelines describe two complementary
in vitro approaches for assessing intrinsic clearance in fish. These assays support the refinement of bioaccumulation predictions without the need for animal testing, thereby supporting the 3Rs principles.
• OECD 319A – Hepatocyte Assay (RT-HEP)
Uses cryopreserved rainbow trout hepatocytes to measure
in vitro intrinsic clearance. This approach reflects the metabolic capacity of intact liver cells and is widely applied to support
in silico bioaccumulation models.
• OECD 319B – Subcellular Fraction Assay (RT-S9)
Utilizes rainbow trout S9 liver fractions to assess clearance potential. This cost-efficient method is well-suited for screening multiple substances and identifying metabolic activity.
Smithers offers both RT-HEP and RT-S9 assays, tailored to your study requirements:
• Radiolabeled and non-radiolabeled test substances, as applicable
• Experienced technical staff with deep knowledge of OECD fish bioaccumulation guidelines
• GLP-compliant studies supporting regulatory acceptance
• Custom study design to align with your development timelines and regulatory strategy
Our scientists are ready to discuss how OECD 319 assays can enhance your chemical safety and bioaccumulation assessments.
Contact us to learn how Smithers can design a testing program tailored to your regulatory and research needs.