The Explosion - or What the MSDS doesn't tell you.

On Monday, June 13th, I was working at home, getting the shopping cart ready for our 15 on the 15th sale, when Christi called, to tell me that the Air Conditioning at work had gone out. T had already called a repair person.   I suggested we have the crew finish the orders from the weekend and then we could close up early. We agreed there was no need for me to go in there. No HVAC repair possible until Tuesday afternoon.

About two hours after Christi's initial call, T, our production manager, called near hysteria. A full gallon bottle of Holy Basil essential oil (Tulsi, Ocimum sanctum) had exploded on the shelf.

 Perhaps a brief explanation of our physical layout is appropriate. Picture two rectangles, one about 2 and a half times longer than it is wide, a bit over a thousand square feet. That is the production and storage area.
At one end, up a short flight of stairs is a smaller square, probably 400 square feet, divided in two. the half nearer the production area is our breakroom, kitchen and office supply storage, through a doorway is the office. Much more space than Christi and I need.  The "upstairs" and "downstairs" have separate heating and cooling units. For reasons unknown, one of the quirks of the air circulation causes the aroma of any oils being poured downstairs to be much stronger in the office.  We have an exhaust fan hanging over the pouring stations, but it really doesn't help. Christi and I will enjoy (or not) what is being poured that day.

 Okay, with that mental image in your mind...  Picture, against one wall of the production room, a set of metal shelves used for bulk storage. Gallon and half gallon amber glass jugs of non-perishable essential oils. (The perishable oils are stored under refrigeration; this is "cool room temperature" storage, under nitrogen.)

Two thoughts entered my mind, first, how to clean it up, and second, what about the other oils?. I told her to start blotting the spill up with paper towels, to wear gloves, and to UNSEAL every other bulk product, to prevent another bottle exploding.  At that point, in all honesty, my main concern was protecting the rest of our inventory. I had never heard of a bottle exploding from heat, although it made logical sense, based on the laws of physics, that it could. I printed out a copy of the MSDS sheet for Holy Basil and headed for the office.

When I arrived at work, most of the bulk products had been cracked open.  Because we didn't know how long the production area would be without air conditioning we started moving product into the walk-in cold room. Priorities were the most costly and/or the most fragile essential oils and blends first, when they were safely stored in the cold room.  After all the bulk oils and blends were stored, we moved the remaining carrier oils, lotions and creams, some of the retail sizes, everything that we were concerned about degrading in extreme heat.

In moving some of the remaining bottles off the bulk storage shelf we found the bottoms covered with a white paste.  The spilled Holy Basil had dissolved the paint on the shelves.  Pause, put on Nitrile gloves. continue stashing products in the cold room or the (air conditioned) warehouse.  At which point we discovered that Holy Basil essential oil will eat through Nitrile gloves.  (Jim discovered that, as the only man available he was nominated to continue the cleanup.)   After the shelves were emptied, the actual shelves were moved outside into the air to be dealt with later.  He cleaned up all that was still damp and "wipeable" with towels. They also went outside in the trash.  Having done all we knew to do at that point, we finished the orders that had been in process, got them to the post office, decided that no one but me would come in on Tuesday, and closed up shop.


On Tuesday I had someone come in to soap and water wash the floor and metal shelf framework, and the Air Conditioner Repair person came.  On Wednesday reopened for business. Since the production area was once again at "cool room temperature" we spent the day moving bulk and retail product out of temporary cold storage and back to their normal spaces. Then we started packing orders from the sale on the 15th. 

My primary concern at that point was the integrity of our inventory.  Extremes of heat and cold can hasten the oxidation of essential oils, as well as the carriers we have, and I was worried about them.  I contacted the two most knowledgeable chemists I know - Robert Tisserand and Tony Burfield, both of whom reassured me that no harm had been done. Robert was even gracious enough to let us quote him:

I don't think you need to be too concerned about quality degradation. In 48 hours or so, only so much oxidation can take place, and that's the only potential problem. Oxidation is a very slow process. I would guess that some of your oils might have lost a week or two of shelf life (out of 2-3 years or so) and I don't think you need to do any more than you are doing.

Essential oils are distilled at very hot temperatures of course, and moving from liquid phase to gas and back is not in itself damaging. The explosion was about vapor pressure building up, and is dramatic and traumatic. But it's no more than that - a build-up of pressure. Shame you lost all that beautiful oil!

Certainly you need to check each oil, but my guess is that they are all going to be fine! Basically, you're cleaning up a mess, and then things can settle back down.

That was a huge relief.  but the mess was far from cleaned up.

Over the course of the next week or 10 days we experienced various repercussions.  Remember I explained that the odd air circulation of our building intensified any aromas upstairs, in the office? The air intake for the "upstairs" air conditioner sits beside Christi's desk.  Air flow tends to be circular - into the office from the break room, around the room past the front door, then past my desk, past Christi's desk and into the intake.

My computer desk sits perpendicular to that airflow.  During the next two or three days I developed contact dermatitis on one side of my face and neck...where the air molecules touched my skin.  

Over the course of the next week Christi became physically ill.  She struggled on for a few days, took some time off, recuperated at home, became ill again immediately upon her return to the office.She experienced nausea, diarrhea, headache, then major major sinus pain and drainage from mucous membrane irritation, her  gastric reflux was affected, she experienced extreme fatigue and skin irritation. She had been sensitized to clove oil years ago, and the Eugenol in the Holy Basil did her in. 

T, downstairs, was moving the computer right next to the area of the spill, on her knees, unplugging cables.  Mind you, the spill had been cleaned up days earlier; the floor scrubbed with soap and water, there was NO essential oil visible.  She ended up having to use our emergency eyewash fountain for the first time ever. The fumes coming off the floor tiles in that corner were enough to burn her eyes.

At this point we did what we should have done the day of the spill; we called for help.  And getting help was not as easy as it sounds.  There are a lot of companies listed that claim to help with chemical spills (which is what we were dealing with.)  I called. they asked me to fax them an MSDS of the product. I did so, along with a GCMS showing that the spill was 65% eugenol. In many cases, I never heard back.


        * First suggestion for your Emergency Plan: Have industrial cleanup numbers on hand. If possible interview them in advance to see who is willing to respond to something that is not a HUGE industrial spill, but none the less is a hazard. 

Finally a local "Air Quality" engineer came to visit. He, at least, knew what an essential oil was, talked of VOC's and contamination.  He gave us some concrete steps to take that we should have taken immediately.  Vic McCauley, from Roscoe Brown, Inc. was the only source of guidance and advice we had.

       * Next suggestion for your plan:   Baking soda or Cat litter. LOTS of it.  Buy it by 20 or 40 lb bags. Have at least one large bag on hand in your workroom or store room, and another in your blending room.

   1.  Baking Soda or Cat Litter.  both substances will absorb VOC's (Volatile Organic Compounds) from the air.  We should have dumped 40 pounds of cat litter on the spill the minute it happened.  Lacking that, we should have spread large, open trays of either on every table in the building, and changed them daily.  This is the single most important step that we could have taken.

2.  We left EVERY fan in the building running 24/7, not just the exhaust fan over the pouring table (no where near the area of the spill.) but the bathroom exhaust fan, the ceiling fans that help rotate the air, ever fan in the building; and left one window cracked open to bring in fresh air. (Had the temperatures not been record-breaking hot, we'd have left doors open while we were here.)

3. We had already known that the exhaust fan we'd built in when we renovated this building was not very effective.  We have installed an oxidizing air cleaner into the AC ducts in the production room.  For three weeks we used a 'stand alone' oxidizing air purifier in the office area.  And daily we filled cookie sheets with baking soda or cat litter, let them stand for 24 hours, and replaced them with fresh.

All of this helped.  Christi was able to return to work, my skin was not getting any worse.  But alone, they were not enough to clean the air in our building, because every surface had been saturated with volatile molecules of Eugenol.

Over the July 4th weekend, we had workmen come in.  The "Industrial Strength Solvent Resistant" floor tile, permanently etched by the spilled essential oil was removed.  The cement floor under the tile was sealed, prior to having new tiles put down.  The two corner walls near the spill were painted with KILZ, to seal any absorbed essential oil, then repainted.

The metal shelf framework was scrubbed down with Acetone (this was Tony Burfield's recommended cleaner.) painted (again, with KILZ) to seal in any splashes of essential oil that did not successfully wash off.  New wooden shelves were cut to fit and painted.  In other words, every thing that had come in direct contact with the spilled oil was either removed or sealed.

That total renovation, plus the new air cleaners took the aromatic level down a few notches.  We still smell Holy Basil when we enter the building, but it is gentler; no longer overwhelming.  We can now also smell *other* aromatics, for the first time in weeks.
I don't know if the building will ever totally be cleared of the remaining traces.  I know all the cardboard shipping boxes are delightfully aromatic now.  We had to move all the bliss bath products out to the warehouse. Now that "the dust has settled' we can inspect them to see how much holy basil they've absorbed and decide whether to dispose of them, or let our clients buy them at clearance.

Too much Holy Basil smells like sweet Clove Bud oil, from the Eugenol. After a month or more of drying down and removal, we are discovering a delightfully gentle floral trace in the dry down.  I don't remember experiencing that aspect in the past.

I think we can safely ensure that our building will never have a problem with insect infestations, and I dare any bacteria to try growing there.