EXPOSURE INVESTIGATION
HYDROGEN SULFIDE IN AMBIENT AIR
DAKOTA CITY/SOUTH SIOUX CITY
DAKOTA CITY/SOUTH SIOUX CITY, NEBRASKA
Table 1a.
Hydrogen Sulfide Peak Concentrations by Date: 1997
Indoor Sampling Location 1 | |
| Date | ppb | Date | ppb | Date | ppb | Date | ppb | Date | ppb |
| 4/3 | 0 | 4/18 | 23 | 5/3 | 0 | 5/18 | >90 | 6/2 | >90 |
| 4/4 | 0 | 4/19 | 28 | 5/4 | 0 | 5/19 | 0 | 6/3 | >90 |
| 4/5 | 4 | 4/20 | 2 | 5/5 | >90 | 5/20 | 17 | ----- | ---- |
| 4/6 | 0 | 4/21 | 0 | 5/6 | 45 | 5/21 | 2 | ----- | ---- |
| 4/7 | 0 | 4/22 | 4 | 5/7 | 0 | 5/22 | 0 | ----- | ----- |
| 4/8 | 0 | 4/23 | 2 | 5/8 | 0 | 5/23 | 15 | ----- | ----- |
| 4/9 | 0 | 4/24 | 31 | 5/9 | 3 | 5/24 | 40 | ----- | ----- |
| 4/10 | 9 | 4/25 | 62 | 5/10 | 0 | 5/25 | 8 | ----- | ----- |
| 4/11 | 2 | 4/26 | >90 | 5/11 | 0 | 5/26 | 15 | ----- | ----- |
| 4/12 | 0 | 4/27 | 8 | 5/12 | 0 | 5/27 | 13 | ----- | ----- |
| 4/13 | 0 | 4/28 | 9 | 5/13 | 3 | 5/28 | 7 | ---- | ----- |
| 4/14 | 0 | 4/29 | 3 | 5/14 | 0 | 5/29 | >90 | ----- | ----- |
| 4/15 | 1 | 4/30 | 3 | 5/15 | 1 | 5/30 | >90 | ----- | ----- |
| 4/16 | 59 | 5/1 | 8 | 5/16 | 0 | 5/31 | >90 | ----- | ----- |
| 4/17 | 84 | 5/2 | 8 | 5/17 | >90 | 6/1 | >90 | ------ | ----- |
ppb = part per billion (0.001 part per million) > = equal or greater than ---- = no sampling occurred |
Table 1b.
Hydrogen Sulfide Concentrations vs. Time
Indoor Sampling Location 1 | |
Date (1997) | Minutes over 5 ppb | Minutes over 20 ppb | Minutes over 90 ppb (off-scale) |
| 4/16 | 120 | 120 | 0 |
| 4/17 | 470 | 260 | 0 |
| 4/18 | 0 | 225 | 0 |
| 4/19 | 475 | 120 | 0 |
| 4/24 | 310 | 125 | 0 |
| 4/25 | 235 | 170 | 0 |
| 4/26 | 560 | 485 | 115 |
| 4/27 | 115 | 0 | 0 |
| 4/28 | 200 | 0 | 0 |
| 5/1 | 105 | 0 | 0 |
| 5/2 | 75 | 0 | 0 |
| 5/5 | 125 | 125 | 30 |
| 5/6 | 375 | 115 | 0 |
| 5/17 | 175 | 130 | 100 |
| 5/18 | 320 | 265 | 130 |
| 5/20 | 450 | 0 | 0 |
| 5/23 | 30 | 0 | 0 |
| 5/24 | 620 | 180 | 0 |
| 5/25 | 145 | 0 | 0 |
| 5/26 | 170 | 0 | 0 |
| 5/27 | 240 | 0 | 0 |
| 5/28 | 240 | 0 | 0 |
| 5/29 | 200 | 185 | 155 |
| 5/30 | 775 | 715 | 200 |
| 5/31 | 305 | 200 | 75 |
| 6/1 | 215 | 200 | 120 |
| 6/2 | 30 | 30 | 30 |
| 6/3 | 55 | 40 | 20 |
| ppb = part per billion (0.001 part per million) |
Indoor Sampling Location 3Table 2a.
Hydrogen Sulfide Peak Concentrations by Date: 1997
Indoor Sampling Location 3 | |
| Date | ppb | Date | ppb | Date | ppb |
| 4/3 | 0 | 4/18 | 5 | 5/3 | 0 |
| 4/4 | 7 | 4/19 | 0 | 5/4 | 1 |
| 4/5 | 0 | 4/20 | 1 | 5/5 | 0 |
| 4/6 | 0 | 4/21 | 3 | 5/6 | 0 |
| 4/7 | 0 | 4/22 | 0 | 5/7 | 2 |
| 4/8 | 0 | 4/23 | 0 | 5/8 | 0 |
| 4/9 | 0 | 4/24 | 0 | 5/9 | 43 |
| 4/10 | 2 | 4/25 | 0 | 5/10 | 2 |
| 4/11 | 0 | 4/26 | 11 | 5/11 | 0 |
| 4/12 | 0 | 4/27 | 0 | 5/12 | 0 |
| 4/13 | 0 | 4/28 | 1 | 5/13 | 0 |
| 4/14 | 0 | 4/29 | 1 | ----- | ----- |
| 4/15 | 0 | 4/30 | 0 | ----- | ----- |
| 4/16 | 0 | 5/1 | 0 | ----- | ----- |
| 4/17 | 2 | 5/2 | 0 | ----- | ----- |
ppb = part per billion (0.001 part per million) ---- = no sampling occurred |
Table 2b.
Hydrogen Sulfide Concentrations vs. Time
Indoor Sampling Location 3 | |
| Date (1997) | Minutes over 5 ppb | Minutes over 20 ppb | Minutes over 90 ppb (off-scale) |
| 4/4 | 135 | 0 | 0 |
| 4/18 | 30 | 0 | 0 |
| 4/26 | 270 | 0 | 0 |
| 5/9 | 435 | 420 | 0 |
Table 3a.
Hydrogen Sulfide Peak Concentrations by Date: 1997
Indoor Sampling Location 4 |
| Date | ppb | Date | ppb | Date | ppb |
| 4/3 | 0 | 4/18 | 0 | 5/3 | 0 |
| 4/4 | 0 | 4/19 | 0 | 5/4 | 0 |
| 4/5 | 2 | 4/20 | 1 | 5/5 | 0 |
| 4/6 | 0 | 4/21 | 0 | 5/6 | 0 |
| 4/7 | 0 | 4/22 | 0 | 5/7 | 0 |
| 4/8 | 0 | 4/23 | 0 | 5/8 | 0 |
| 4/9 | 0 | 4/24 | 0 | 5/9 | 0 |
| 4/10 | 0 | 4/25 | 0 | 5/10 | 1 |
| 4/11 | 0 | 4/26 | 0 | 5/11 | 0 |
| 4/12 | 0 | 4/27 | 0 | 5/12 | 3 |
| 4/13 | 0 | 4/28 | 0 | 5/13 | 0 |
| 4/14 | 0 | 4/29 | 15 | 5/14 | 0 |
| 4/15 | 0 | 4/30 | 0 | ----- | ----- |
| 4/16 | 0 | 5/1 | 0 | ----- | ----- |
| 4/17 | 0 | 5/2 | 0 | ----- | ----- |
ppb = part per billion (0.001 part per million) ---- = no sampling occurred |
Table 3b.
Hydrogen Sulfide Concentrations vs. Time
Indoor Sampling Location 4 | |
| Date (1997) | Minutes over 5 ppb | Minutes over 20 ppb | Minutes over 90 ppb (off-scale) |
| 4/29 | 75 | 0 | 0 |
| ppb = part per billion (0.001 part per million) |
Table 4a.
Hydrogen Sulfide Peak Concentrations by Date: 1997
Indoor Sampling Location 5 |
| Date | ppb | Date | ppb | Date | ppb |
| 4/3 | 0 | 4/18 | 0 | 5/3 | 0 |
| 4/4 | 0 | 4/19 | 0 | 5/4 | 0 |
| 4/5 | 1 | 4/20 | 16 | 5/5 | 0 |
| 4/6 | 0 | 4/21 | 3 | 5/6 | 0 |
| 4/7 | 0 | 4/22 | 6 | 5/7 | 0 |
| 4/8 | 4 | 4/23 | 0 | 5/8 | 0 |
| 4/9 | 0 | 4/24 | 0 | 5/9 | 0 |
| 4/10 | 0 | 4/25 | 0 | 5/10 | 0 |
| 4/11 | 0 | 4/26 | 2 | 5/11 | 0 |
| 4/12 | 0 | 4/27 | 0 | 5/12 | 0 |
| 4/13 | 5 | 4/28 | 0 | 5/13 | 0 |
| 4/14 | 0 | 4/29 | 4 | ------ | ------ |
| 4/15 | 0 | 4/30 | 5 | ------ | ------ |
| 4/16 | 0 | 5/1 | 0 | ------ | ------ |
| 4/17 | 0 | 5/2 | 0 | ------ | ------ |
ppb = part per billion (0.001 part per million) ---- = no sampling occurred | |
Table 4b.
Hydrogen Sulfide Concentrations vs. Time
Indoor Sampling Location 5 | |
| Date (1997) | Minutes over 5 ppb | Minutes over 20 ppb | Minutes over 90 ppb (off-scale) |
| 4/16 | 15 | 0 | 0 |
| 4/17 | 90 | 0 | 0 |
| 4/18 | 30 | 0 | 0 |
| 4/19 | 15 | 0 | 0 |
| ppb = part per billion (0.001 part per million) |
Table 5a.
Hydrogen Sulfide Peak Concentrations by Date: 1997
Indoor Sampling Location 6 | |
| Date | ppb | Date | ppb | Date | ppb | Date | ppb | Date | ppb |
| 4/3 | 2 | 4/18 | 0 | 5/3 | 0 | 5/18 | 3 | 6/2 | 0 |
| 4/4 | 0 | 4/19 | 4 | 5/4 | 3 | 5/19 | 0 | ------ | ------ |
| 4/5 | 4 | 4/20 | 11 | 5/5 | 0 | 5/20 | 0 | ------ | ------ |
| 4/6 | 0 | 4/21 | 18 | 5/6 | 0 | 5/21 | 1 | ------- | ------ |
| 4/7 | 0 | 4/22 | 0 | 5/7 | 60 | 5/22 | 4 | ------ | ------ |
| 4/8 | 6 | 4/23 | 0 | 5/8 | 9 | 5/23 | 0 | ------- | ------- |
| 4/9 | 0 | 4/24 | 0 | 5/9 | 0 | 5/24 | 0 | ------ | ------- |
| 4/10 | 7 | 4/25 | 9 | 5/10 | 0 | 5/25 | 0 | ------- | ------- |
| 4/11 | 0 | 4/26 | 0 | 5/11 | 0 | 5/26 | 0 | ------- | ------- |
| 4/12 | 0 | 4/27 | 0 | 5/12 | 0 | 5/27 | 0 | ------- | ------- |
| 4/13 | 7 | 4/28 | 0 | 5/13 | 0 | 5/28 | 8 | ------ | ------- |
| 4/14 | 0 | 4/29 | 17 | 5/14 | 40 | 5/29 | 0 | ------ | ------- |
| 4/15 | 0 | 4/30 | 0 | 5/15 | 21 | 5/30 | 0 | ------ | ------- |
| 4/16 | 2 | 5/1 | 11 | 5/16 | 2 | 5/31 | 0 | ------- | ------ |
| 4/17 | 5 | 5/2 | 0 | 5/17 | 0 | 6/1 | 0 | ------ | ------ |
ppb = part per billion (0.001 part per million) ---- = no sampling occurred |
Table 5b.
Hydrogen Sulfide Concentrations vs. Time
Indoor Sampling Location 6 | |
| Date (1997) | Minutes over 5 ppb | Minutes over 20 ppb | Minutes over 90 ppb (off-scale) |
| 4/13 | 30 | 0 | 0 |
| 4/17 | 15 | 0 | 0 |
| 4/20 | 150 | 0 | 0 |
| 4/21 | 150 | 0 | 0 |
| 4/29 | 230 | 0 | 0 |
| 5/1 | 190 | 0 | 0 |
| 5/7 | 170 | 60 | 0 |
| 5/8 | 115 | 0 | 0 |
| 5/14 | 85 | 55 | 0 |
| 5/15 | 225 | 20 | 0 |
| 5/28 | 15 | 0 | 0 |
| ppb = part per billion (0.001 part per million) |
Table 6.
Hydrogen Sulfide Peak Concentrations by Date: 1997
Outdoor Sampling Location
53 - 1,500 ppb detection range | |
| Date | ppb | Date | ppb | Date | ppb | Date | ppb | Date | ppb |
| 4/3 | ----- | 4/18 | ----- | 5/3 | ------ | 5/18 | 1301 | 6/2 | 892 |
| 4/4 | ------ | 4/19 | ------- | 5/4 | ------ | 5/19 | 0 | 6/3 | 0 |
| 4/5 | ------ | 4/20 | ------ | 5/5 | ------ | 5/20 | 0 | ------ | ----- |
| 4/6 | ------ | 4/21 | ------ | 5/6 | ------ | 5/21 | 0 | ------ | ------ |
| 4/7 | ------ | 4/22 | ------ | 5/7 | ------ | 5/22 | 0 | ------ | ----- |
| 4/8 | ----- | 4/23 | ------ | 5/8 | ------ | 5/23 | 0 | ------ | ------ |
| 4/9 | ----- | 4/24 | ------ | 5/9 | ------ | 5/24 | 0 | ------- | ------ |
| 4/10 | ------ | 4/25 | ------- | 5/10 | ------ | 5/25 | 0 | ------ | ------ |
| 4/11 | ------ | 4/26 | ------- | 5/11 | ------ | 5/26 | 0 | ------ | ------ |
| 4/12 | ------ | 4/27 | ------ | 5/12 | ------ | 5/27 | 319 | ------ | ------ |
| 4/13 | ------ | 4/28 | ------ | 5/13 | ------ | 5/28 | 0 | ------ | ------ |
| 4/14 | ------ | 4/29 | ------ | 5/14 | ------ | 5/29 | 1137 | ------ | ------ |
| 4/15 | ------ | 4/30 | ------ | 5/15 | 0 | 5/30 | 419 | ------ | ------ |
| 4/16 | ------ | 5/1 | ------ | 5/16 | 253 | 5/31 | 402 | ------ | ------ |
| 4/17 | ------ | 5/2 | ------ | 5/17 | 324 | 6/1 | 1375 | ------ | ------ |
ppb = part per billion (0.001 part per million) ---- = no sampling occurred |
Table 7a.
Hydrogen Sulfide Peak Concentrations by Date: 1997
Outdoor Sampling Location
0 - 90 ppb detection range | |
| Date | ppb | Date | ppb | Date | ppb | Date | ppb | Date | ppb |
| 4/3 | ----- | 4/18 | ----- | 5/3 | ------ | 5/18 | >90 | 6/2 | >90 |
| 4/4 | ------ | 4/19 | ------- | 5/4 | ------ | 5/19 | >90 | 6/3 | 0 |
| 4/5 | ------ | 4/20 | ------ | 5/5 | ------ | 5/20 | >90 | ------ | ----- |
| 4/6 | ------ | 4/21 | ------ | 5/6 | ------ | 5/21 | 0 | ------ | ------ |
| 4/7 | ------ | 4/22 | ------ | 5/7 | ------ | 5/22 | 0 | ------ | ----- |
| 4/8 | ----- | 4/23 | ------ | 5/8 | ------ | 5/23 | 49 | ------ | ------ |
| 4/9 | ----- | 4/24 | ------ | 5/9 | ------ | 5/24 | 19 | ------- | ------ |
| 4/10 | ------ | 4/25 | ------- | 5/10 | ------ | 5/25 | 10 | ------ | ------ |
| 4/11 | ------ | 4/26 | ------- | 5/11 | ------ | 5/26 | 0 | ------ | ------ |
| 4/12 | ------ | 4/27 | ------ | 5/12 | ------ | 5/27 | >90 | ------ | ------ |
| 4/13 | ------ | 4/28 | ------ | 5/13 | ------ | 5/28 | 74 | ------ | ------ |
| 4/14 | ------ | 4/29 | ------ | 5/14 | ------ | 5/29 | >90 | ------ | ------ |
| 4/15 | ------ | 4/30 | ------ | 5/15 | 0 | 5/30 | >90 | ------ | ------ |
| 4/16 | ------ | 5/1 | ------ | 5/16 | >90 | 5/31 | >90 | ------ | ------ |
| 4/17 | ------ | 5/2 | ------ | 5/17 | >90 | 6/1 | >90 | ------ | ------ |
ppb = part per billion (0.001 part per million) ---- = no sampling occurred > = greater or equal to |
Table 7b.
Hydrogen Sulfide Concentrations vs. Time
Outdoor Sampling Location |
| Date (1997) | Minutes over 5 ppb | Minutes over 20 ppb | Minutes over 90 ppb (off-scale) |
| 5/16 | 15 | 15 | 15 |
| 5/17 | 65 | 50 | 30 |
| 5/18 | 240 | 180 | 105 |
| 5/19 | 10 | 10 | 5 |
| 5/20 | 140 | 110 | 40 |
| 5/23 | 15 | 15 | 0 |
| 5/27 | 105 | 60 | 45 |
| 5/28 | 105 | 45 | 0 |
| 5/29 | 235 | 225 | 190 |
| 5/30 | 415 | 315 | 155 |
| 5/31 | 145 | 100 | 45 |
| 6/1 | 160 | 130 | 105 |
| 6/2 | 35 | 35 | 30 |
| ppb = part per billion (0.001 part per million) |
Table 8.
Comparison of Location 1: Hydrogen Sulfide
Indoor Air vs. Ambient Air at Adjacent Location | |
| Date (1997) | Indoors Minutes Over 90 ppb (off-scale) | Outdoors Minutes Over 90 ppb (off-scale) | Outdoors Peak H2S Value ppb (high conc. tape) |
| 4/26 | 115 | ------ | ----- |
| 5/5 | 30 | ------ | ----- |
| 5/17 | 100 | 30 | 324 |
| 5/18 | 130 | 105 | 1301 |
| 5/29 | 155 | 190 | 1137 |
| 5/30 | 200 | 155 | 419 |
| 5/31 | 75 | 45 | 402 |
| 6/1 | 120 | 105 | 1375 |
| 6/2 | 30 | 30 | 892 |
| 6/3 | 20 | 0 | 0 |
ppb = part per billion (0.001 part per million) ---- = no sampling occurred |
Table 9.
Health Impacts of and Regulatory Guidelines for
Hydrogen Sulfide in Ambient | |
| Air Concentration inparts per billion (ppb) | Health/Regulatory Significance |
| 0.02 - 0.07 | Levels in air in an undeveloped area in Colorado [11] |
| 0.11 - 0.33 | Average U.S. background levels in air [12] |
| 0.72 | EPA RfC: an estimate of daily human exposure to a potential hazard that is likely to be without risk of deleterious effects during a lifetime [14] |
| 8 | Odor Threshold [10] |
| 90 | ATSDR Intermediate MRL: an estimate of daily human exposure that is likely to be without an appreciable risk of adverse, noncarcinogenic effects from 15 to 356 days of exposures [4] |
| 100 | ERPG-1: the maximum airborne concentration below which itbelieved that nearly all individuals could be exposed for up to 1hour without experiencing other than mild, transient adversehealth effects or without perceiving a clearly definedobjectionable odor [15] |
| 500 | ATSDR Acute MRL: an estimate of daily human exposure that is likely to be without an appreciable risk of adverse, noncarcinogenic effects from 14 or fewer days of exposures [4] |
| 3,000 - 5,000 | offensive odor, moderately intense [16] |
| 10,000 | TLV; NIOSH 10-minute ceiling REL; obvious and unpleasant odor |
| 15,000 | OSHA 15-minute ceiling |
| 20,000 - 30,000 | Strong and intense odor [16] |
| 30,000 | ERPG-2: the maximum airborne concentration below which itis believed that nearly all individuals could be exposed for upto 1 hour without experiencing or developing irreversible orother serious health effects or symptoms which could impair anindividual's ability to take protective action [15]. |
| 50,000 | NIOSH recommends worker evacuation; marked irritation of eyes and respiratory tract |
| 100,000 | IDLH, loss of smell in 3-15 minutes [16] |
RfC = Inhalation reference dose ERPG = Emergency Response Planning Guidelines MRL = Minimal Risk Level TLV = Threshold limit value NIOSH = National Institute for Occupational Safety and Health REL = Relative exposure limit OSHA = Occupational Health and Safety Administration IDLH = Immediately dangerous to life and health |

Figure 1. Dakota City Hydrogen Sulfide Exposure Investigation Sampling Locations/Potential Sources
Figure 1 Map ID
GRAPHS 1-13

Outdoor Sulfur/H2S Concentrations - May 16-17, 1997

Outdoor Sulfur/H2S Concentrations - May 18, 1997

Outdoor Sulfur/H2S Concentrations - May 19-20, 1997

Outdoor Sulfur/H2S Concentrations - May 20, 1997

Outdoor Sulfur/H2S Concentrations - May 23, 1997

Outdoor Sulfur/H2S Concentrations - May 24-25, 1997

Outdoor Sulfur/H2S Concentrations - May 27, 1997

Outdoor Sulfur/H2S Concentrations - May 27, 1997

Outdoor Sulfur/H2S Concentrations - May 29-30, 1997

Outdoor Sulfur/H2S Concentrations - May 30-31, 1997

Outdoor Sulfur/H2S Concentrations - May 31, 1997

Outdoor Sulfur/H2S Concentrations - June 1, 1997

Outdoor Sulfur/H2S Concentrations - June 2-3, 1997
TRIP REPORTS
The following section was not available in electronic format for conversion to HTML at the time of preparation of this document. To obtain a hard copy of the document, please contact:
Agency for Toxic Substances and Disease Registry
Division of Health Assessment and Consultation
Attn: Chief, Program Evaluation, Records, and Information Services Branch, E-56
1600 Clifton Road NE, Atlanta, Georgia 30333
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