Preliminary results of an ongoing public health investigation indicate that a powerful sporicidal cleaning agent used in some 500 hospitals may be linked to wheezing, watery eyes, and asthma-like symptoms in healthcare workers, the National Institute for Occupational Safety and Health (NIOSH) reports.

The situation is emblematic of an ongoing dilemma in healthcare. Strong products needed to protect patients from an epidemic of Clostridium difficile — a spore-former difficult to remove from the hospital environment — may trigger respiratory symptoms in housekeeping and other healthcare workers exposed to the chemicals during cleaning.

“There really has to be a balance between patient safety and worker safety,” says Megan Casey, RN, MPH, a NIOSH nurse epidemiologist who is investigating the case. “We need to make sure that worker safety is not compromised as we continue this battle against healthcare-associated infections.”

The NIOSH investigation began after healthcare workers at Magee-Womens Hospital in Pittsburgh contacted the agency and expressed concerns about their reactions to a new cleaning product in use at the facility. Employees complained of symptoms that included burning eyes, nose, and throat; cough, headache, dizziness, nausea, asthma exacerbation, and skin burns and rashes.

“The process here at NIOSH is that employers or at least three employees can request a Health Hazard Evaluation,” Casey says. “We will come into a workplace and do an assessment for a potential hazard. In this case, the product was introduced in March of 2014, but it wasn’t until roughly a year later that employees requested a health hazard evaluation from us.”

NIOSH conducted a hazard evaluation report at the hospital, concluding in an April 12, 2016, interim report to the facility that the “findings support the conclusion that exposure to OxyCide is associated with adverse health effects and indicate the need to minimize employee exposures.”1

OxyCide is an EPA-registered non-bleach sporicide and virucide manufactured by Ecolab in St. Paul, MN. The primary ingredients are acetic acid [AA], peroxyacetic acid [PAA], and hydrogen peroxide [HP]. The product safety indications say it requires no personal protective equipment when diluted with water by an automated dispenser before use.

“OxyCide is proven effective against several harmful bacteria and viruses that are known to cause healthcare-associated infections, including Clostridium difficile bacteria spores,” Roman Blahoski, director of Global Communications at Ecolab, told HEH via email. “C. diff infections are linked to 29,000 deaths each year. Hospitals across the country are finding that OxyCide is a key component of their programs to battle healthcare-acquired infections.”

C. diff is, indeed, a formidable risk to patients that has stubbornly resisted national reduction efforts. The current major push to rein in antibiotic use should reduce C. diff, which has a clear route to the gut once patients lose commensal bacteria via antimicrobial therapy. As it stands right now, however, healthcare workers may be caught in a crossfire as powerful chemicals are used to kill persistent C. diff spores on environmental surfaces.

“[Employee health professionals should] encourage workers to report any symptoms that might be related to this product or any product containing acetic acid, peroxyacetic acid, or hydrogen peroxide,” Casey tells Hospital Employee Health. “One of our main findings was that product users reported more work-related symptoms than non-product users. These are symptoms that improved for the employee on days off or on vacation.”

Summary of Findings

A branch of the CDC, NIOSH recently published a summary of the findings in the MMWR2 that included the following key points:

  • Researchers interviewed 79 (78%) of 101 current environmental services staff about their health.
  • Among the 68 employees who worked with the product, the most commonly reported health outcomes were watery eyes (46%), nasal problems (41%), asthma-like symptoms (28%), use of allergy medicine (16%), and shortness of breath (16%).
  • A total of 30 (44%) reported at least one work-related health outcome. Most commonly reported work-related symptoms were watery eyes (29%) and nasal problems (22%).
  • Among 10 respondents with self-reported physician-diagnosed asthma, six reported that something at work brought on or worsened their asthma, and three mentioned the cleaning product specifically by name.
  • Air sampling results for HP ranged from 6 parts per billion (ppb) to 511 ppb; for AC, from 7 ppb to 530 ppb; and for PPA, from 1 ppb to 48 ppb. All measurements for HP and AA were below their respective occupational exposure limits of 1,000 ppb and 10,000 ppb. No full-shift exposure limit has been established for PAA.

With regard to that last point, investigators did the air sampling in proximity to workers cleaning with the product. As noted above, the exposures were within established limits, but the CDC/NIOSH published report spoke to the lack of resolution on several aspects of these particular chemical agents.

“Few assessments of worker exposure to hydrogen peroxide, acetic acid, and peroxyacetic acid in healthcare settings have been conducted, despite the use of this product in more than 500 hospitals nationally,” investigators noted.2 “Two previous investigations conducted by the Occupational Safety and Health Administration at hospitals in Pennsylvania and Vermont … in response to employee concerns about symptoms reported while using this product, were limited to air sampling. No health assessments were performed.”

In the CDC\NIOSH evaluation, environmental services staff members reported work-related symptoms despite measured air sampling exposures that were below the established full-shift limits for hydrogen peroxide and acetic acid. However, because both hydrogen peroxide and peroxyacetic acid are strong oxidants, it is possible that the mixture of hydrogen peroxide and peroxyacetic acid contributed to the symptoms reported by workers, the investigators noted.

“We found a higher prevalence of asthma in departments with higher hydrogen peroxide measurements,” Casey adds. “Hydrogen peroxide is one of the chemical components in this cleaner. We looked at what are called standardized morbidity ratios. We took the number of people who had diagnosed asthma and compared that to the U.S. adult population. We found significantly more asthma than we would expect in the U.S. adult population on these departments that had higher hydrogen peroxide measurements.”

Hospital: ‘No Comment’

Magee-Womens Hospital spokesperson Gloria Kreps told HEH the hospital had no comment on the NIOSH report.

In a previous interview with a Pittsburgh newspaper, Kreps was quoted as saying, “We are committed to maintaining safe, sanitary facilities for our patients and employees. Ecolab … represents that OxyCide is an EPA-approved cleaner that is safe when used correctly and reduces patient exposure to dozens of dangerous organisms. We have no reason to doubt them. … As with any product, its safe use by our employees is of utmost importance and any issues regarding its safe use are investigated immediately.”3

Indeed, though raising general awareness and recommending several specific measures be taken by the hospital, NIOSH has decided for now that the evidence in the ongoing investigation is not conclusive enough to recommend stronger action on the cleaning product.

“Due to the limitations of our study we can’t definitively determine the exact timing or the causality of these [worker] symptoms to the product,” Casey says. “However, this product has been listed as an asthmagen by the Association of Occupational and Environmental Clinics [AOEC]. We also know that the chemical components of this cleaning product [HP, PAA, and AA] have caused asthma in some case reports we have seen. We are certainly concerned, but due to the limitation of our study we can’t make a definitive determination.”

Asthma issues

HEH confirmed that the AOEC has added OxyCide to its list of asthmagens, which is defined by NIOSH as substances that can cause asthma.1 The AOEC classified the cleaning product as a “sensitizer,” which, according to NIOSH, is a substance that can cause an immune response and adverse respiratory effects even at low levels of exposure.

“The AOEC developed an exposure code listing for clinical use by our members in 1994,” says Katherine H. Kirkland, DrPH, MPH, executive director of the association. “Since that time, we have expanded the listing of occupational and environmental exposures and we have developed a protocol for designating some of the exposures as asthmagens.”

In consultation with two AOEC physicians clinicians, Kirkland clarified via email that, “an individual may develop asthma due to exposure to a sensitizing agent at very low levels of exposure, and this condition may become permanent and require treatment even after exposure has stopped. The longer an individual is exposed to an asthmagen, the greater the risk of developing asthma. The person must be exposed to the chemical/substance that caused the initial reaction. This is not a list of substances that aggravate an individual’s asthma, but a list of substances that cause asthma. There is a much larger group of chemicals/substances that can aggravate someone’s asthma once they have asthma. That said, there are many substances on this list that would also aggravate someone with asthma if they already had asthma.”

The AOEC recommends following the basic NIOSH occupational safety and health hierarchy to protect workers from such hazards

“We recommend that employers provide programs to protect workers from exposure to substances that can eliminate or minimize exposure to chemicals that cause asthma,” the AOEC told HEH.

The specific measures NIOSH recommended to Magee-Womens included the following:

  • not using the cleaner in non-patient areas,
  • use of personal protective equipment,
  • additional return airflow be provided in two janitorial closets,
  • implement a reporting system that would allow employees to report work-related symptoms with the option to remain anonymous, and
  • discontinue use of the product as a spray cleaner in favor of rags or wipes.

Spraying Stopped

“Efforts should be made to help workers try to reduce their exposure to these products,” Casey says. “With regard to the specific hospital, they have limited product spraying. Originally they were putting the product into spray bottles and spraying it. They no longer do that — they only use it in a wipe form and they also provided goggles to the workers because they were concerned about splashing in disposing the products.”

Given the unresolved issues, NIOSH is considering whether additional recommendations for PPE equipment should be made.

“The safety data sheet for this product currently recommends no personal protective equipment,” Casey says. “Right now that is one of the things that we are looking at and considering whether we should be recommending various levels of protective equipment when using these types of products. Certainly, for workers in a hospital having trouble with this product or a similar product, they need to talk to their supervisor and try to reduce their exposure as much as possible.”

There is also the lingering question whether the worker symptoms are all acute and self-limiting or could result in chronic health problems.

“That is still one of the questions that we are investigating,” she says. “We did a separate survey which looked at the acute effects. So essentially, our industrial hygienist interviewed staff members using the product after their shifts to get a sense of the acute symptoms. This [other] survey that we did asked questions in terms of the last 12 months — things like diagnosis of asthma. We tried to look at the chronic conditions in our survey and we also had a survey that addressed acute conditions, but we are still analyzing that data and taking a look at both surveys.”


  1. NIOSH. HETA 2015-0053. Interim Report 3. April 12, 2016.
  2. CDC. Notes from the Field: Respiratory Symptoms and Skin Irritation Among Hospital Workers Using a New Disinfection Product — Pennsylvania, 2015. MMWR 2016;65(15);400–401.
  3. Nuttall, R. OxyCide is supposed to make hospitals cleaner and safer for patients, but what about the staff that has to use it? Pittsburgh City Paper February 18, 2015.