Persistent pollution of genetic materials in a typical laboratory environment

Area of Science:

• Environmental Science
• Molecular Biology
• Biosafety

Background:

• The COVID-19 pandemic heightened concerns about biohazard environmental pollution, especially with increased genetic engineering studies.
• Nucleic acid tests for SARS-CoV-2 and widespread use of genetic materials necessitate an understanding of laboratory environmental safety.

Purpose of the Study:

• To investigate genetic material pollution within a typical laboratory setting during plasmid development.
• To identify pollution sources, transmission routes, and contamination levels of genetic materials in the laboratory environment.

Main Methods:

• Real-Time quantitative-Polymerase Chain Reaction (RT-qPCR) was used to detect targeted DNA segments in environmental samples.
• Surface, aerosol, and liquid samples were collected from laboratories and public areas.
• Analysis included 79 environmental samples from genetic material operations.

Main Results:

• Half of the environmental samples (38/79) tested positive for nucleic acid pollution.
• Persistent contamination was found in all tested laboratories and extended to public areas.
• High concentrations of targeted DNA were detected in liquid (1.92 × 10^8 copies/uL) and surface (5.22 × 10^7 copies/cm^2) samples, and in indoor air (mean 74 copies/L).

Conclusions:

• Spills and improper disposal of plasmid products are primary sources of genetic material pollution.
• Laboratories with low biosafety levels require designated experimental zones, advanced biosafety cabinets, and efficient cleaning systems.
• Persistent environmental contamination by genetic materials is a concern in low biosafety level laboratories.