5. Page 5 of 5 C:\Users\jrobinson.CHEMDAQ2\Dropbox\Food & Beverage\Symptoms of Exposure to Peracetic Acid Vapor Feb 2016.doc Conclusions  There is very little published data on the effect of low concentration PAA vapor on humans.  The odor threshold is around 50 ppb, well below the ACGIH STEL TLV.  0.5 ppm is the threshold for irritation to mucous membranes and eyes; 1.5 ppm is associated with slight to tolerable discomfort to nasal membranes and eyes for exposure durations up to 20 minutes; and 2 ppm and above results in significant irritation.  The PAA values around 0.5 ppm recorded at National Beef are at the threshold of irritation and so any irritation experienced by workers would be mild and probably not sufficient for them to report it.

4. Page 4 of 5 C:\Users\jrobinson.CHEMDAQ2\Dropbox\Food & Beverage\Symptoms of Exposure to Peracetic Acid Vapor Feb 2016.doc ChemDAQ’s Customers We installed a peracetic acid monitoring system in a beverage company using a PAA aseptic filling line. Workers were complaining of irritation of their eyes and noses. When the system was first installed it was continuously in alarm and often over 2 ppm. The company has since upgraded their air handler and are keeping the concentrations low and worker complaints have stopped. Discussion The development of occupational exposure limits includes more than just the obvious symptoms of exposure. For example, the OSHA permissible exposure limit for carbon monoxide is 50 ppm, but there are no obvious symptoms of exposure at 100 ppm. The exposure limit is set at a low value because of the risk of harm from non-symptomatic effects and include other data such as animal studies and biological tests for mutagenicity. The panels who determine exposure limits also include a large safety factor and so exposure limits are usually below the concentration where symptoms are problematic. One reason for taking a conservative approach is that the effects of exposure can vary greatly from one person to the next. One person may notice a smell but their neighbor has significant eye irritation. The goal of this report is to assess what symptoms may be expected at various concentrations of PAA and thus at what concentration people are likely to complain. While there many published reports on the extent of occupational exposure, there have only been a few reports correlating the symptoms in humans to the PAA concentration. Based on those reports, the answer appears to be that most people will experience symptoms worth complaining about for PAA concentrations between 1.5 and 2 ppm. There will however be some people who experience irritation at lower concentrations and some hardy souls who will not complain for even higher concentrations. The ChemDAQ monitors read up to 0.5 ppm during national Beef tests and workers in the area were not complaining. Based on the published reports discussed above, 0.5 ppm is considered the threshold for irritation, so people may start to experience irritation, but would probably not experience enough irritation to complain. During ChemDAQ’s on- site survey at national Beef, the readings went up to about 0.3 and 0.4 ppm. There was definitely an odor of PAA during these tests but little or no irritation was experienced.

3. Page 3 of 5 C:\Users\jrobinson.CHEMDAQ2\Dropbox\Food & Beverage\Symptoms of Exposure to Peracetic Acid Vapor Feb 2016.doc 4 In contrast You et al (2006) found that 2.1 mg/m 3 over 8 hours resulted in lacrimation, eye and skin irritation and coughing. 5 ACGIH STEL TLV The ACGIH documentation for development of the STEL TLV relied on the same reports regarding symptoms as a function of PAA concentration as the AEGL committee. 6 NIOSH IDLH NIOSH is currently considering an Immediately Dangerous to Life and Health Limit for PAA and has circulated a draft document. 7 The IDLH is the maximum (airborne concentration) level above which only a highly reliable breathing apparatus providing maximum worker protection is permitted. IDLH values are based on a 30 minute exposure duration. In regard to human symptoms of low concentration exposure, the IDLH committee is using the same references are the AEGL and ACGIH TLV exposure committees. 4 http://www.epa.gov/sites/production/files/2014- 09/documents/peracetic_acid_final_volume8_2010_0.pdf 5 “Evaluation of the toxicity data for peracetic acid in deriving occupational exposure limits: A mini-review. N. Pechacek, M. Osorio, J. Caudill, B. Peterson, toxicology Letters (233, (2015), 45- 57, citing You Y, Bai Z, Gao X, (2006), “Peracetic acid exposure assessment during outbreak of SARS in Tianjin, China Epidemiol. 17, S217-S218. 6 Peracetic Acid documentation for STEL TLV. ACGIH 2014. 7 http://www.cdc.gov/niosh/docket/review/docket156a/pdfs/g1-013---peracetic-acid-cas-79-21- 0.pdf

2. Page 2 of 5 C:\Users\jrobinson.CHEMDAQ2\Dropbox\Food & Beverage\Symptoms of Exposure to Peracetic Acid Vapor Feb 2016.doc AEGLs for Peracetic Acid 3 (mg/m 3 ) 10 min 30 min 60 min 4 hr 8 hr AEGL 3 60 mg/m 3 30 mg/m 3 15 mg/m 3 6.3 mg/m 3 4.1 mg/m 3 The AEGLs are very conservative as is shown by the peracetic acid technical document that was part of the AEGL development. The AEGL-1 value is 0.52 mg/m 3 (0.17 ppm) for all exposure durations from 10 min to 8 h. This value was derived from an exposure concentration of 1.56 mg/m3 (0.5 ppm), which, according to Fraser and Thorbinson (1986), is expected to cause no discomfort and according to McDonagh (1997) is not immediately irritating but would be unpleasant for an extended period of time. Therefore, 1.56 mg/m 3 (0.5 ppm) is considered to be the threshold for irritation to mucous membranes and eyes. An intraspecies uncertainty factor of 3 was applied to 1.56 peracetic acid mg/m3, because peracetic acid is a corrosive/irritant substance and the effects, which are confined to the upper respiratory tract, are expected to be similar for individuals within the population. Irritation occurs at 0.5 ppm or higher over long durations for some individuals. The AEGL-2 value is 1.56 mg/m 3 (0.5 ppm) for all exposure durations from 10 min to 8 h based on an exposure concentration of 4.7 mg/m 3 (1.5 ppm), which, according to Fraser and Thorbinson (1986), is expected to be associated with slight to tolerable discomfort to nasal membranes and eyes for exposure durations up to 20 min. There was no increase in irritation with exposure duration. ... The AEGL-2 value is .... Exposure to aerosols generated from diluted Peratol was associated with lacrimation at 5 ppm (15.6 mg/m 3 ), extreme discomfort and irritation to mucous membranes at 2.0 ppm (6.23 mg/m 3 ).... Slight to tolerable discomfort in the nose is experienced at 1.5 ppm and above for up to 20 minutes, significant irritation over 2 ppm. The results for higher PAA concentrations are summarized in the table below (data cited from Fraser & Thompson (1986).

1. Page 1 of 5 C:\Users\jrobinson.CHEMDAQ2\Dropbox\Food & Beverage\Symptoms of Exposure to Peracetic Acid Vapor Feb 2016.doc Symptoms of Exposure to Peracetic Acid Vapor Richard Warburton February 2016 Introduction During a recent visit to National Beef in Liberal, KS, the question was raised concerning at what concentration of peracetic acid (PAA) vapor would people start to experience irritation and so complain. This report provides a summary of the available literature to answer this question. Peracetic Acid Exposure Symptoms (from literature) Odor PAA has a strong vinegar like smell and it has an odor threshold around 0.05 ppm 1 (50 ppb). Therefore, PAA can be smelt at a concentration well below occupational exposure limits (e.g. ACGIH STEL TLV = 0.4 ppm (15 min TWA). Irritation Irritation occurs at a significantly higher concentration than the odor. AEGLs 2 AEGLs represent threshold exposure limits for the general public and are applicable to emergency exposure periods ranging from 10 min (min) to 8 hs (h). Three levels— AEGL-1, AEGL-2 and AEGL-3—are developed for each of five exposure periods (10 and 30 min, 1 h, 4 h, and 8 h) and are distinguished by varying degrees of severity of toxic effects. AEGLs for Peracetic Acid 3 (mg/m 3 ) 10 min 30 min 60 min 4 hr 8 hr AEGL 1 0.52 mg/m 3 0.52 mg/m 3 0.52 mg/m 3 0.52 mg/m 3 0.52 mg/m 3 AEGL 2 1.6 mg/m 3 1.6 mg/m 3 1.6 mg/m 3 1.6 mg/m 3 1.6 mg/m 3 1 Water Quality Industry News — Day_2_Tues_Sept_30_2014 http://pubs.royle.com/article/Proxitane+Peracetic+Acid%E2%80%A6+Environmentally+Compati ble+Treatment+of+Wastewater/1812262/0/article.html 2 Peracetic Acid, Acute Exposure Guideline Levels; Acute Exposure Guideline Levels for Selected Airborne Chemicals: Volume 8; Committee on Acute Exposure Guideline Levels; Committee on Toxicology; National Research Council, http://www.epa.gov/sites/production/files/2014- 09/documents/peracetic_acid_final_volume8_2010_0.pdf 3 http://www.epa.gov/aegl/peracetic-acid-results-aegl-program