| Source
Newsletter 2006 issue 2 |
|
 |
Changing Procedures
| |
 |
| |
Catherine Zimmer, MnTAP health care and laboratory specialist, observed as MnTAP intern Elizabeth Quan demonstrated a lab procedure. |
Unless your lab
is pioneering research, such
as experimenting with germ enlargers and banana sharpeners,* there’s a good chance it can reduce the hazardous waste it generates.
Standard lab processes, such as gas chromatography and atomic absorption, generate lab waste when solvents are used to extract compounds for analysis. Clinical, commercial and environmental laboratories that repeatedly use common analytical procedures might discover that with diligence they can reduce their hazardous waste.
Finding the time to run test experiments and validate the results, likely running duplicate tests, can be difficult with busy testing schedules. Labs can make equipment and process changes that reduce waste. Here are two examples.
Minnesota Department of Agriculture
By changing a laboratory procedure, the Environmental Analysis Section of the Minnesota Department of Agriculture (MDA) Laboratory Services Division eliminated 99 gallons of methylene chloride waste annually. The procedure that extracted pesticides for water analysis required a liquid-to-liquid extractor (LLE) that used methylene chloride to extract pesticides from samples.
MDA wanted to improve worker safety and keep the hazardous chemical out of the environment. The lengthy procedure time—18 to 24 hours—was another incentive to find an alternate method.
MDA had reviewed other pesticide extraction options. But with time constraints, lab staff requested a MnTAP intern to organize literature on waste reduction and on several alternative extraction methods using specific vendor equipment.
“The intern provided the manpower to explore the options available for reducing methylene chloride,” noted Phil Hansen, MDA environmental analysis unit supervisor. “It was good to have a dedicated person instead of many people contributing small amounts of time to the project.”
Under MDA guidance, the intern evaluated alternatives to LLE and determined that solid phase extraction (SPE) cartridges were the best option. Through discussions with vendors and peers, as well as trial-and-error experience, MDA learned that SPE filter media had changed and now some types could trap analytes that would not adhere to filter media in the past.
By using SPE, the lab reduced methylene chloride use by 85 to 90 percent, saving $3,300 in purchase and disposal costs. Reducing extraction and evaporation time saved $36,600 per year.
Los Alamos National Laboratory
Los Alamos National Laboratory, operated by the University of California for the National Nuclear Security Administration of the U.S. Department of Energy (DOE), eliminated the chemical formamide—a hazardous chemical—from its process to determine the nucleotide sequence of DNA. Formamide traditionally is used to re-suspend DNA after denaturing.
Lab staff discovered that substituting a waterbased solution gave better sequencing results with none of the potential hazards of formamide. By eliminating formamide, genetic sequencing waste became completely nonhazardous.
This change also substantially reduced the amount of paperwork involved with operations. Reduced waste disposal, procurement costs and labor saved approximately $78,000 annually.
More information on laboratory pollution prevention is available through MnTAP's Laboratories Web page or call MnTAP for assistance. See the complete MDA intern project summary.
* See video clips of the experiments of Muppets Dr. Bunsen Honeydew and his assistant Beaker.
|
