In June 2020, the small town of Merrillville, IN, received a visit from the Indiana Department of Environmental Management (IDEM). Merrillville is home to Microbac, a laboratory that offers analytical testing services for food, environmental, antimicrobial products, and pharmaceuticals. With more than 20 facilities across the United States, they are required to follow local water regulations, in addition to safety data sheets.
However, what the IDEM found was not in line with either.
IDEM cited the Microbac facility for multiple violations of federal guidelines that establish test procedures for water pollutant analysis. Some of the lab’s machines that analyzed water acidity were not calibrated at the standard required by the U.S. Environmental Protection Agency.
And unfortunately, this wasn’t the first time this had happened. In 2014, a Microbac facility in Pennsylvania was also found to be fraudulently misrepresenting water testing results. The Pennsylvania Department of Environmental Protection fined Microbac $125,000, and the lab gave up its accreditations.
This is never a situation a lab wants to find itself in.
To avoid water pollution, fines, and the possibility of having your accreditations revoked, here are some ways laboratories can help keep their water waste clean.
Substitute harmful chemicals
The best way to avoid harmful chemicals getting into the water is to avoid hazardous materials in the first place. Some compounds, especially halogenated compounds, are particularly dangerous and should never be washed down drains or otherwise disposed of improperly, as they can contaminate pipes and water sources. Duke University has a list of hazardous chemicals in the lab and safer substitutes you can use, including the following:
PMSF (phenylmethylsulfonyl fluoride) and DFP (diisopropyl phosphorofluoridate) are widely used for protease inhibition during protein isolation, but they are highly reactive with acids and with water. You can usually replace these with Pefabloc® SC.
If using sodium azide, order it in a diluted solution rather than in a powder. The powder can travel through the air and contaminate water and surfaces. If you can’t get diluted solution sodium azide, swap it for 1–2% 2-chloroacetamide as a preservative.
When possible trade ethidium bromide for SYBR Safe, GelRed and GelGreen, GelStar, EZ-Vision, or SafeGLO.
For freezing point depression, don’t use hazardous acetamide; use stearic acid instead.
Another recommended substitute is to trade out mercury thermometers for electronic thermometers or alcohol-based ones. This is especially important for measuring the temperature of water baths, which have a reputation for causing thermometers to burst, and it’s best to avoid having mercury contaminate the water.
Use correct disposal methods
If you do end up with hazardous materials in the laboratory, dispose of them in a way that won’t harm groundwater. In order to use correct disposal methods, you should first know where your water is going. If it drains to a septic system or directly to surface water, you’ll need to be extra careful—chemicals can directly contaminate local ecosystems! Even if your laboratory drains water to a publicly owned treatment works (POTW) or an on-site treatment plant, you should still follow all local and federal laws for safe disposal.
Argonne National Laboratory took this point seriously. To double-check where all their water drained to, they conducted an experiment. Argonne listed all the drains in its laboratory—more than 2,000 of them—that were not known to be tied into either the sanitary or laboratory sewers. These included floor drains, lab slop sinks, and cooling towers. Then, researchers poured dyed water into the drains and tested water at known stormwater collection points to see if any of the drains were leaking. If the dye was found in the water, they knew the drain shouldn’t be used for any kind of toxic chemicals. Argonne labeled those drains as such to help prevent water contamination. This test helped correctly dispose of chemicals because they knew which drains to use and which ones to avoid. Argonne’s Green Infrastructure includes bioswales that receive rainwater runoff to slow water infiltration and filter out pollutants.
An additional way you can use correct disposal methods is to neutralize solutions before pouring them down the drain. Common substances like alkanols, sugars and alkoxyalkanols can make it into the sewer system—provided their concentration is 1% or lower—but chlorinated hydrocarbon waste, cyanide compounds and heavy metals should be avoided. It is also recommended to keep drain disposal volumes to less than four liters per day.
Keep storage areas and machinery clean
Improper storage of chemicals and machinery is another common source of water contamination. To help your lab avoid polluting water, make sure that your storage areas are clean and well-organized. This will make it easy to identify any unfortunate spills that happen during experiments, giving you the opportunity to take action before they pollute water. Label all chemicals clearly—even adding expiration dates on those with a limited lifespan—so that when their time has come, proper disposal can be guaranteed.
Be sure to keep your machinery clean too. Some laboratory equipment, such as centrifuges, can generate wastewater that may contain hazardous chemicals. To prevent water pollution, laboratories should install and maintain equipment in accordance with best practices when you drain and wash out equipment. Whether you’re working with a huge autoclave or a small glass Erlenmeyer flask, you’ll want the equipment to be clean—which includes making sure the water you rinsed it out with is properly treated.
Conclusion
Our planet's most precious resource, water, is something that we must all defend and protect. Poor waste management practices can have devastating consequences for people, animals, plant ecosystems, sewer systems, and more. While using responsible waste practices can help your company avoid fines and avoid PR disasters, safe water disposal is also a key component to creating a sustainable set of guidelines for your laboratory and can even help save you money with efficient best practices.
Learn more about how Life science can protect waterways
Water stewardship practices can factor into grant applications, the NIH is taking eco-friendliness into account when reviewing applications.
The Living Greenhouse Wastewater Treatment Facility at New England Biolabs