Biosafety Level 1 (BSL1) Recombinant DNA Waste

Bio Safety Update web

According to the NIH Guidelines for Research Involving Recombinant DNA Molecules, BSL1 contaminated recombinant DNA (rDNA) liquid or solid waste (including transgenic rodents, fish, flies, etc.) must be decontaminated before disposal.

The following types of BSL1 rDNA waste are EXEMPT from the NIH Guidelines and can be disposed of as non-biohazardous waste (in regular trash), in closed clear or white bags to contain odors prior to pickup by janitorial staff. **

  1. BSL1 rDNA waste which is not in organisms or viruses (e.g., DNA, RNA, oligos waste, PCR waste, Microarrays, etc.).
  1. BSL1 rDNA waste from experiments which use Escherichia coli K-12 host-vector systems. The system uses only non-conjugative plasmids as vectors (e.g., pBR322, pBR313) and does not contain conjugation proficient plasmids or generalized transducing phages.
  1. BSL1 rDNA waste from experiments involving Saccharomyces cerevisiae and Saccharomyces uvarum host-vector systems.
  1. BSL1 rDNA waste that contains less than one-half of any eukaryotic viral genome that is propagated and maintained in cells in tissue culture.

** Please ensure that exceptions described above involve rDNA waste that utilizes ONLY Risk Group 1 biological materials and does not present a significant risk to health or the environment.

BSL1 rDNA waste that does not adhere to the exemptions above must be disposed of as follows:

  • Liquid BSL1 rDNA waste must be decontaminated by mixing one volume of undiluted bleach with nine volumes of liquid biohazardous waste (final dilution of 1:10) for 30 minutes. This can be drain-disposed if not mixed with chemical or radioactive material thereafter.
  • Solid BSL1 rDNA waste must be disposed of in red biohazardous waste bags placed inside a hard-sided medical waste container with a tight-fitting lid in place at all times (when not in active use).

Please do not hesitate to contact the UCSF Biosafety Officer (514-2824) if you have additional questions.

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Posted:  April 13, 2011