What: Shares of Stericycle (SRCL -0.62%) were hammered on Friday, and were down more than 20% by the early afternoon. Driving the downdraft were surprisingly weak revenue growth and a complete lack of earnings growth. Neither sat well with investors, who were expecting the company to continue to grow both by double digits.

So what: Stericycle reported revenue of $718.6 million, which was just up 7.6% over the third quarter of last year. Worse yet, non-GAAP earnings were flat at just $1.08 per share while GAAP earnings plunged 51.6% to just $0.47 per share. Both results missed the company's guidance by a wide margin.

The company's earnings release was completely devoid of details on why its results slipped, other than the fact that foreign currency fluctuations affected revenue by $33 million. It wasn't until the conference call that the company was more forthcoming about what happened during the quarter. CEO Charlie Alutto said that the company's results were "unfavorably impacted by the following key factors: the strengthening of the U.S. dollar, lower hazardous-waste volume from our industrial customers, and some higher-than-anticipated expenses in certain lines of business. 

While the weight of the strong dollar was to be expected given its impact in prior quarters, the big surprise was the lower hazardous waste volumes given that those are typically pretty stable.

The company's guidance for the full year was also a bit weaker than was expected, with one analyst on the call saying he was "flummoxed, which doesn't happen very often. The forecast seems about $100 million to $150 million light to me on the revenues." Alutto responded to this comment by saying that the "industrial waste weakness that we've seen in the third quarter is going to continue on and probably accelerate a little bit more in the fourth quarter. So we're being very conservative on the industrial waste."

Now what: The concern is that this issue with slowing industrial waste could be more than just a short-term bump in the road, which is a big reason the stock is getting hammered today. While the company expects conditions to improve next year, investors, who are a bit shell-shocked by the results, don't appear to be buying management's confidence that volumes will recover next year.