Many labs at Homewood use High Performance Liquid Chromatographs (HPLCs); these instruments allow separation and analysis of a wide variety of chemicals in small quantity. HPLCs use carrier solvents, chemicals that carry the compounds being analyzed through the machine. Consequently, HPLCs can produce large amounts of chemical waste. This can lead to several problems.
- Laboratories sometimes place HPLC waste containers on the floor where they can be kicked. Not only can this cause a chemical spill, but it can also result in physical injury to researchers to accidentally kick or trip over the waste bottle. This risk is easily mitigated by placing the waste containers off the floor—on the bench, in a cabinet, etc.
- HPLC waste containers are sometimes stored without secondary containment, that is, a tray or outer bottle to prevent leaks from spreading. Secondary containment must be large enough to contain the entire contents of the leaking waste bottle, and it must be made of a material (usually plastic) resistant to the chemicals it might have to contain.
- Sometimes, laboratories will route HPLC waste lines directly into bottles such as recycled solvent bottles. While there is nothing wrong in principle with this, there are several issues.
- Often, the tubing is routed into the waste bottle without any consideration for overflow. Special purpose valves, often built into specialty bottle caps, are available to shut off flow in the waste line if the waste bottle fills up. Most HPLCs will shut themselves off if the waste line is blocked—check your instrument manual.
- Sometimes, the tubing is secured and “sealed” to the bottle with aluminum foil or Parafilm—this is ineffective in stopping vapor from being released into the lab. The result is that all lab occupants must breathe the vapor from the HPLC waste; this is also an environmental violation. Again, special HPLC collection systems and bottle caps are available to provide a positive seal.
- Using recycled bottles can also be an issue if the original contents of the bottle are not compatible with the HPLC waste. Never use reactive chemical bottles such as those for nitric or perchloric acid for solvent waste, regardless of how well you think you’ve cleaned them.
Secondary containment tubs and overpacks are available from laboratory equipment suppliers such as Fisher Safety. Other suppliers, such as Cole-Parmer, make sealed HPLC cap systems. Contact the Laboratory Safety Advocate, Dr. Daniel Kuespert, CSP, at [email protected]for assistance in obtaining special cap systems suitable for your instrument.