One time, I was at a job site sampling groundwater from nearly 50 water supply wells. Each water supply well had an entire cooler?s worth of sample bottles to fill. With additional duplicate and field blank samples, you can do the math on how many coolers we had to haul around and store and how many bags of ice we had to purchase to keep them cool. And then there?s breakage — we had multiple 1-liter bottles break during shipment. Unless you put an entire roll of bubble wrap on each of those pesky 1-liter amber bottles, you are guaranteed that at least one or two will shatter into a million pieces.
Conversely, the other day I had to go to the local medical center for some routine blood work. Two small tubes of blood and a few minutes later, I was out the door and on my way home. ?If only environmental sampling was so easy,” I thought. “When?s the last time anyone had to submit 1 liter of blood for a clinical test?!?
Peter Schulert, CEO of ESC Lab Sciences in Mt. Juliet, TN, asked himself the same question and decided to be a leader of change within the environmental laboratory industry. Here, he shares ESC?s experience in reducing solvent emissions and sample volume.
Contaminating the Environment We Are Trying to Protect
From the beginning of my career over 25 years ago, it struck me as quite ironic that in order for our lab to tell you how much PAH was in your groundwater sample, we had to release over a pound of methylene chloride into the atmosphere. The EPA provided an exemption for environmental laboratories so that we could emit these solvents without an air permit. Virtually every environmental lab — public or private — used this exemption. On a per square foot basis, environmental labs consumed more chemicals and energy and discharged more waste than a typical heavy industry!
But that was almost 3 decades ago. Surely technology has improved and the industry has advanced so that we are no longer forced to make this trade-off of polluting the environment in order to generate the data we need to protect the environment.
While the technology has advanced, there has not been the regulatory or industry leadership to change. At ESC, we saw this challenge early on and were determined to make our process more sustainable.
Reducing Solvent Emissions
We were not satisfied with emitting under the EPA lab exclusion. This posed a challenge, because no environmental laboratory vendor provided the technology to recover solvent. All of the concentration technology was open vessel, and it introduced so much air and moisture that the exhaust was virtually impossible to condense (we made several attempts).
We decided to research pharmaceutical vendors and found a vacuum concentration system in Europe, manufactured by Buchi. Because no air or moisture was introduced, it was relatively easy to condense the solvent exhaust. ESC is now recovering over 90% of solvents. We were the first and I believe the only environmental lab to have an effective solvent recovery program. We sold our recovered solvent to a glue manufacturer and won a national award for introducing solvent recovery to the environmental lab industry.
And that was great, but it brought us back to our original question: ?Why are we using so much solvent in the first place?” ?
Large Volume Injection
Current gas chromatograph technology only allows for injection of 1 microliter of extract onto the column. That’s why a liter of sample and 180 mLs of solvent is necessary to extract and concentrate down to 1 mL. If we could inject more of the extract, we could use a smaller sample and less solvent. So our driving question became, ?How could we inject more sample extract onto the column??
Large Volume Injection Technology has been around for a while. We explored it over 15 years ago for this reason: we wanted to reduce sample size and the amount of solvent used. At that time, the technology was research grade and would not support our production.
A few years ago, Agilent introduced an advanced GC injection technology that would support Large Volume Injection in a production lab. We purchased two instruments and began setting up TPH methods using a flame ionization detector. These were the simplest methods to convert.
Once we saw the technology working, we immediately saw the potential to convert virtually all of our semi-volatile methods. So we placed an order for 16 additional instruments. Agilent told us it was the largest single GC order they had ever received. We converted PAH next and more recently have converted BNA, pesticides, and PCBs.
Beyond the solvent reduction, this technology improves our sustainability from almost every aspect. The shipping footprint is reduced, breakage is virtually eliminated, and cold room storage space is reduced. But most importantly, it saves our clients considerable time in the field collecting the samples because only 40 to 100 mL of sample volume is required instead of 1 liter.
Raise the Bar
Next time you are filling up a 1-liter PAH bottle, I?d like you to ask yourself, why, if the technology is available, shouldn?t we raise the bar and begin scrutinizing common environmental laboratory practices against the clinical and pharmaceutical laboratory industries, industries that are far more efficient? ?Why shouldn?t we, as environmental companies, be on the leading edge of more sustainable processes?
Peter Schulert has led ESC Lab Sciences for 25 years, first as Business Development Manager and currently as CEO. Under Peter’s leadership, ESC has grown from five people on staff to a staff of over 250 and is the largest and most certified facility in the environmental lab industry. Peter credits ESC’s focus on sustainability as a key to its success.