Stinkhorn, Back to School and Environmental Monitoring

environmental monitoring laboratory

The summer is over, the kids are back to school, and in the Northeast it is getting cooler, darker and damper. Already there are dead leaves on the ground and friends with allergies are popping diphenhydramine and blaming leaf mold, as good an indicator that air flora is changing as an open Malt Extract Agar settling plate. Reflecting on these seasonal changes, on my way into the lab last week, I noticed a large fungus growing in the mulch that wasn’t there just the day before.

Mutinus elegans comes up often this time of year, poking up out of compost and dead leaves. This phallic fungus goes by a few common names elegant stinkhorn, dog stink horn, devil’s lipstick because of its shape but also because it smells downright awful — like dead carrion.  As any other microbiologist would, I got down to take a good look and to snap some pictures, and noticed the sticky tips were covered with ants and flies. The awful smell attracts these insects, which in turn help distribute the fungal spores. This is not the sort of rude guest you want poking around your Labor Day barbecue! Back in the straight laced Victorian day, Charles Darwin’s eldest daughter used to roam the woods around her house with a spear, collecting and burning these basidiomycetes, in order to protect the morals of maids.

But what interested me that morning was how quickly this thing erected itself from spore to full on fruiting body — all in one evening.  It got me thinking about environmental monitoring. Recent revisions to USP <797> upheld the twice a year air sampling strategy that some sterile compounding pharmacies cling to. For me, this stink horn was a rude reminder of why this is not a sound strategy.

Microflora change in quantity and quality through the seasons. Bacteria and mold found in spring will be much different than those found in the fall. And even day to day, variances in humidity, wind, foot traffic, gowning, travel will impact what microbes are brought into the sterile manufacturing area  no matter how diligent the attempts to control. We monitor the air to know what the threats are, not to triple clean and get a good grade. We cannot react to what we aren’t monitoring.

environmental monitoring lab

Take a look at our laboratory data. We monitor daily and weekly, depending on the site. The trend witnessed in an uncontrolled ISO 8 area shows we must react more stringently at different times of year. And we do react, with increased air filtration and sanitization.  Our reaction to the fluctuating background helps assure our clients are not wasting time with false positive test results. (All microbial analysis is performed in ISO 5 hoods by the way, this information helps us assess what we are protecting against) But we wouldn’t be reacting if we didn’t have these data. Imagine compounding sterile drugs with out these data.

environmental monitoring laboratory

Or conversely, consider New England Compounding Center and it’s black mold. Interesting the owners also had a mattress recycling center about 100 feet upwind of the sterile compounding pharmacy (true polymath entrepreneurs). Can you imagine the mold that would grow on old mattresses kept outdoors in the rain Whether this was the source or not, who knows. But the fungus showed up in the fall in the lab. Good thing they were monitoring. Bad thing they didn’t do anything about it. See our EM Blog for more information on how to react to Alert and Action Levels.

Perhaps the reason some sterile compounders do not monitor more frequently is cost. But EM doesn’t have to be expensive. For ongoing monitoring, between biannual certification events, FOCUS Labs can set customers up with equipment, media and training to perform their your own EM. See our link on Lab in a Box and call us to discuss further. What you can’t see CAN kill you, and ignorance is NOT bliss. Let us help, give us a call.

(610) 866-7272

USP 797 Proposed Revision July 2018 — Summary of Microbiological Testing Impact

USP 797 testing lab

The USP published its second proposed revision to USP <797> Pharmaceutical Compounding — Sterile Preparations. Significant input from stakeholders was received after the original revision a few years ago, including over 8,000 written documents. The result is a document that looks much different than the original proposal. Here is a high level view of changes with a microbiological impact from the original method last revised in 2008.


There are now two categories of Compounded Sterile Product (CSP) versus the original three of Low, Medium and High Risk. The two categories (Category 1 and Category 2) are based on the compounding conditions, the probability of microbial growth, and the time period in which they can be used. Basically, if you are assigning a Beyond Use Date (BUD) of >12 hours at Controlled Room Temperature (CRT) or >24 hours at refrigerated temperature, you are Category 2. Additional testing and validation are required.

Environmental Monitoring (EM):

Disappointingly in my view, the minimum requirement for air sampling, viable and non viable, regardless of category, is still every six months. Two single snap shots over a year’s time will not give an accurate picture of the microflora in your facility or nor are two points a trend that will expose how well your gowning, disinfecting, engineering, and other processes are under control. See our piece about EM Investigations. Most of our compounding customers sample more frequently than twice a year.

Surface samples have increased to at least monthly. Unfortunately the Action Levels for Surface Samples in ISO 5 areas remain >3 cfu per contact plate. 3 colonies on a 25 cm square sterile surface where sterile compounding occurs is 3 more than what should be considered sterile.

Air levels have rightfully decreased, to <1 cfu/cubic meter in an ISO 5 PEC.

Microbial Identification:

The confusing language from the current chapter has been clarified to state that plates which exceed action level should be identified to genus with the assistance of a microbiologist. FOCUS microbiologists perform microbial identifications by either genetic or biochemical profiling, always resulting in at least a genus ID.


Recommends a single media and the following incubation times for air and surface sampling: Tryptic Soy Agar (TSA) at 30 – 35C for 48 to 72 hours, then transferred to 20 – 25C for 5 – 7 days. This is a change from the previous suggestion of of Malt Extract Agar. There are advantages and disadvantages to this approach. An advantage is saving on the cost of a specialized fungal media. A disadvantage is the enhanced ability of MEA to actually culture wild mold versus TSA (we have data demonstrating this), and a lengthened incubation period before you can react to Action Levels.


There is a much enhanced section on how to select and use antimicrobial agents for the pharmacy. And for the first time, there is direct mention of sporicidal agents that have been shown to effective against Bacillus species, to be used at least monthly. See our piece about disinfectant efficacy


New detail is present on demonstrating that terminally sterilized CSP’s use a process to achieve a Sterility Assurance Level (SAL) of 10-6. Validation of cycles is required, utilizing Biological Indicators including Geobacillus stearothermoophilus for steam sterilization and Bacillus atrophaeus for dry heat sterilization.


Many pharmacies utilize depyrogenation ovens to remove potential endotoxin contamination from vials and other compounding equipment. The proposed chapter requires that the effectiveness be established and verified annually with endotoxin challenge vials, that result in a 3 log reduction of endotoxin.

Release Testing:

All Category 2 CSP’s which have been assigned a BUD must have a sterility test performed — according to USP <71> or a validated alternative method. There has been a lot of confusion regarding Rapid Microbial Methods (RMM) for compounded product release, with some regulators stating that anything other than USP <71> is unacceptable under any conditions. It is encouraging to see science win out in this proposed revision.

Bacterial Endotoxin Tests are also required for all Category 2 CSPs assigned a BUD.

Preservative Efficacy Testing

If a compounded multi dose container is designed to contain more than one dose, and will be entered mulitple times, it should contain a preservative. The proposed revisions require multi-dose preparations be tested by USP <51> Antimicrobial Effectiveness Tests.


We hope this high level review of proposed changes that may impact your microbiological testing needs has been helpful. It is wonderful that the USP has listened to its stake holders. We have one more chance to get our comments in. Click here for more detail. November 30, 2018 public comment period will close.

FOCUS Laboratories now offers a turnkey solution for compounding pharmacies’ monthly sampling needs – the 797 Box. Contact us for more information!

(610) 866-7272