Risk Assessment Pt2. K.E. Kelly University of Utah

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1 Risk Assessment Pt2 K.E. Kelly University of Utah

2 Reminders/Updates I will post the solu.on to HW#1 on Tuesday evening. - Presenta.on topics and schedules are up. Please review the schedule. I have done my best to address your schedule conflicts. I also just had a speaker reschedule. Now, the first presenta.ons are next week: - 9/20 VW Emissions Scandal, Troy Petrie, Jason Henderson - 9/22 Winter-.me ozone in Utah's Uinta basin, Emir Rahislic - 9/22 Electric versus gasoline vehicles, Kyle Branch - 9/22 Biofuels, McKenna Buck, Mike Morgan - We can discuss when your outlines are due

3 Reminders/Notes - I removed the Williams presenta.on from the class website as the speaker s request. It is now in Canvas (Williams99.pdf). - Example fact sheet on hydraulic fracturing Thanks to Tony Long - Steven Cano - remote learning is looking for a project #1 parter

Example 1a - Breathing Toluene A refinery worker works in a shop that has a constant input of toluene from the parts cleaning tanks of 5.2 mg/min. What is the worker s intake rate.

4 Example 1a - Breathing Toluene A refinery worker works in a shop that has a constant input of toluene from the parts cleaning tanks of 5.2 mg/min. What is the worker s intake rate. (Stock - Flow Problem). We are going to look at risk, but first we need to determine the concentration in the room. Toluene release from tanks Equilibrium concentration Flow out, ventilation room, Vol = 10m 3 & air change rate = 2 per hr

5 Example 1 - Need concentration

6 Example 1 - Need concentration Room 10$m 3 5.2$mg/min

7 Example 1 - Need concentration Room 10$m 3 Air$exchange$rate$of$2$per$hour 5.2$mg/min 10#m 3 10#m 3

8 Example 1 - Need concentration Room 10$m 3 Air$exchange$rate$of$2$per$hour 5.2$mg/min 10#m 3 10#m 3 ="20"m 3 /hr

9 Example 1 - Need concentration Room 10$m 3 Air$exchange$rate$of$2$per$hour 5.2$mg/min 10#m 3 10#m 3 ="20"m 3 /hr C toluene = 5.2 mg min 60 min hr hr mg 3 = m 4m 3

10 Example 1b - Toluene Intake Concentration (CA) of toluene in the room 15.6 mg/m 3 Average adult body weight (BW) = 70 kg Inhalation rate (IR) = 0.53 m 3 /hr Exposure frequency (EF) = 260 days/yr Exposure duration (ED) = 30 years Averaging time (ΔT) = 10,950 days = 30 years * 365 days/yr Absorption factor is assumed to be 1 and isn t shown in equation.

11 Example 1 - Intake!"#$%&' () %) +$, =. /01234'! :;' =!"#$%&' 45 () = '46 :; *)+,-. :; >?@ <= <38 98'.B-CD E8'*)' 931' ' 98'.B-CD' ="2.02 () *)+,-.

12 Example 2 - Ingestion of Contaminants in Drinking Water An adult drinks water containing 0.05 mg/l benzene and 0.5 mg/l toluene for 30 years. Estimate the intake rate of each. Benzene is a carcinogen, and toluene is a noncarcinogen. Note benzene and toluene solubility in water are approximately 1.8 g/l and 0.5 g/l, respectively. Calculate the intake rate.

13 Example 2 - Ingestion of Contaminants in Drinking Water Cw = concentration in the water (mg/l) IR = ingestion rate (2 l/day) EF = exposure frequency (days/yr) ED = exposure duration (yr) BW= body weight (70 kg) ΔT = averaging time For non-carcinogens ΔT = 365 days/year * exposure duration For carcinogens ΔT = lifetime (70 years) * 365 days per year

14 Example 2!"#$%&' () %) +$, =. /'! ' mg/l toluene (non-carcinogen)!"#$%&' () 1 h6 +$, () 0.5 %) +$, = 1 2' +$, 24 +$, 365,&$6 30',&$69 70'%)' 365' +$,9 = 0.014,6 ' 30',&$69' 0.05 mg/l benzene (carcinogen) () %) +$,!"#$%&' () 1 () 0.05 %) +$, = 1 2' +$, 365 +$,,&$6 30',&$67 () 70'%)' 365' +$,7 = 6.12':'10;<,6 ' 70',&$67' %) +$,

15 Risk Characterization Risk = Toxicity * Exposure Slightly different calculations for cancer vs. non-cancer effects

16 Risk Characterization: Non-Carcinogens Compare estimated dose with the reference dose (RfD) HQ = Intake/RfD Intake - to convert RfC to a dose: Inhalation dose (mg/kg-day) = RfC (mg/m 3 ) * 20 m 3 /day / 70 kg If HQ < 1, typically not a concern. If HQ>1, need further study. You can sum several simultaneous exposures to the same target organ/endpoint Hazard Index (HI) = HQ 1 + HQ 2 + HQ 3 +

17 Risk Characterization: Non-Carcinogens Cumulative Effects Chemical Estimated dose (mg/kg-day) Reference dose (mg/kg-day) HQ Target / Toluene kidney o-cresol xylene decreased body weight neurotoxicity decreased body weight mortality Total 1.13 RfD and target targets from: EPA IRIS

18 Risk Characterization: Non-Carcinogens Cumulative Effects Chemical Estimated dose (mg/kg-day) / Reference dose (mg/kg-day) HQ Target Toluene kidney o-cresol / / xylene decreased body weight neurotoxicity decreased body weight mortality Total 1.13 RfD and target targets from: EPA IRIS

19 Risk Characterization: Non-Carcinogens Cumulative Effects Chemical Estimated dose (mg/kg-day) / Reference dose (mg/kg-day) HQ Target Toluene kidney o-cresol / / xylene decreased body weight neurotoxicity decreased body weight mortality Total 1.13 RfD and target targets from: EPA IRIS

20 Risk Characterization: Non-Carcinogens Cumulative Effects Chemical Estimated dose (mg/kg-day) / Reference dose (mg/kg-day) HQ Target Toluene kidney o-cresol / / xylene decreased body weight neurotoxicity decreased body weight mortality Total 1.13 RfD and target targets from: EPA IRIS

21 Risk Characterization: Non-Carcinogens Cumulative Effects Chemical Estimated dose (mg/kg-day) Reference dose (mg/kg-day) HQ 1.13 Target Toluene kidney o-cresol xylene Total RfD and target targets from: EPA IRIS / / / decreased body weight neurotoxicity decreased body weight mortality Decreased weight HI = 1.13 >1 possibly unacceptable exposure Kidney HI = 10.1 > 1 possibly unacceptable

22 Risk Characterization: Non-Carcinogens Cumulative Effects Added o-cresol & xylene as an example - did not calculate dose Chemical Estimated dose (mg/kg-day) Reference dose (mg/kg-day) HQ 1.13 Target Toluene kidney o-cresol xylene Total RfD and target targets from: EPA IRIS / / / decreased body weight neurotoxicity decreased body weight mortality Decreased weight HI = 1.13 >1 possibly unacceptable exposure Kidney HI = 10.1 > 1 possibly unacceptable

23 How does a dose of a carcinogen effect humans? Cancer slope factors (CSF) estimate the risk of cancer associated with exposure to a carcinogenic or potentially carcinogenic substance. It is an upper bound, approximating a 95% confidence limit, on the increased cancer risk from a lifetime exposure to an agent.

24 How does a dose of a carcinogen effect humans? Cancer slope factors (CSF) estimate the risk of cancer associated with exposure to a carcinogenic or potentially carcinogenic substance. It is an upper bound, approximating a 95% confidence limit, on the increased cancer risk from a lifetime exposure to an agent. CSFs are developed using models that include data from animal studies at higher concentrations and epidemiological data on human effects.

25 Risk Characterization: Carcinogens Incremental probability of the occurrence of cancer over a lifetime as a result of exposure to the agent. Incremental Excess Lifetime Cancer Risk (IELCR) = Cancer Slope Factor * Lifetime Average Daily Dose Cumulative Total Risk = IELCR1 + IELCR2 + IELCR3 +.

26 Risk Characterization: Carcinogens Cumulative Effects Chemical Estimated dose (mg/kgday) Slope factor (mg/kgday) IELCR Target -1 * Benzene 6.12 x x 10-5 Kidney MED 7 Liver MEDD 0.7 Liver Total 1.8 x 10-5 Kidney MED: methyl ethyl death; MEDD: methyl ethyl double death RfD and target targets from: EPA IRIS with some modifications for the example

27 Risk Characterization: Carcinogens Cumulative Effects Chemical Estimated dose (mg/kgday) Slope factor (mg/kgday) IELCR Target -1 * Benzene 6.12 x x 10-5 Kidney * MED 7 Liver MEDD 0.7 Liver * Total 1.8 x 10-5 Kidney MED: methyl ethyl death; MEDD: methyl ethyl double death RfD and target targets from: EPA IRIS with some modifications for the example

28 Risk Characterization: Carcinogens Cumulative Effects Chemical Estimated dose (mg/kgday) Slope factor (mg/kgday) IELCR Target -1 * Benzene 6.12 x x 10-5 Kidney * MED 7 Liver MEDD 0.7 Liver * Total 1.8 x 10-5 Kidney MED: methyl ethyl death; MEDD: methyl ethyl double death RfD and target targets from: EPA IRIS with some modifications for the example

29 Risk Characterization: Carcinogens Cumulative Effects Chemical Estimated dose (mg/kgday) Slope factor (mg/kgday) IELCR Target -1 * Benzene 6.12 x x 10-5 Kidney * MED 7 Liver MEDD 0.7 Liver * Total 1.8 x 10-5 Kidney MED: methyl ethyl death; MEDD: methyl ethyl double death RfD and target targets from: EPA IRIS with some modifications for the example

30 Kidney IELCR = 1.7 x 10-5 > 10-6 = possibly unacceptable exposure Risk Characterization: Carcinogens Cumulative Effects Liver IECLR = 1.4 x 10-5 > 10-6 = possibly unacceptable exposure The risk of unacceptable exposure can vary between 1: 10,000 and 1: 1 million. For this Estimated example, I use Slope 1 in 1 million. dose factor Chemical IELCR Target (mg/kgdayday) (mg/kg- -1 * Benzene 6.12 x x 10-5 Kidney * MED 7 Liver MEDD 0.7 Liver * Total 1.8 x 10-5 Kidney MED: methyl ethyl death; MEDD: methyl ethyl double death RfD and target targets from: EPA IRIS with some modifications for the example

31 Risk Assessment and Policy Underpinning many health and environmental regulations: Clean Air Act (hazardous air pollution regulations) Clean Water Act (governs water discharge regulations) OSHA regulations (PELs) Resource Conservation and Recovery Act (Superfund) Safe Drinking Water Act (drinking water standards) Toxic Substances Control Act (PCBs, asbestos, and lead-based paint rules)

32 Risk Assessment and Policy Underpinning many health and environmental regulations: Clean Air Act (hazardous Not air pollution all environmental regulations) regulations use the same types Clean Water Act (governs of water standards discharge regulations) OSHA regulations (PELs) Resource Conservation and Recovery Act (Superfund) Safe Drinking Water Act (drinking water standards) Toxic Substances Control Act (PCBs, asbestos, and lead-based paint rules)

33 Risk Assessment and Policy Underpinning many health and environmental regulations: Clean Air Act (hazardous Not air pollution all environmental regulations) regulations use the same types Clean Water Act (governs of water standards discharge regulations) CAA protect public health with OSHA regulations (PELs) an adequate margin of safety Resource Conservation and Recovery Act (Superfund) Safe Drinking Water Act (drinking water standards) Toxic Substances Control Act (PCBs, asbestos, and lead-based paint rules)

34 Risk Assessment and Policy Underpinning many health and environmental regulations: Clean Air Act (hazardous Not air pollution all environmental regulations) regulations use the same types Clean Water Act (governs of water standards discharge regulations) CAA protect public health with OSHA regulations (PELs) an adequate margin of safety Resource Conservation and Recovery Act (Superfund) Pesticides can be licensed if they do not Safe Drinking cause Water any Act unreasonable (drinking water risks standards) to man or the environment taking into account the Toxic Substances economic, Control social Act and (PCBs, environmental asbestos, and costs lead-based paint and benefits rules) of the use of any pesticide

35 HW2 You now should have all of the information you need for HW2.

36 Costs & Benefits of the CAA Cases prevented (2020) Adult mortality particles 230,000 Infant mortality particles 280 Mortality ozone 7100 Chronic bronchitis 75,000 Acute myocardial infarction 200,000 Asthma exacerbation 2,400,000 Emergency room visits 120,000 Lost school days 5,400,000 Lost work days 17,000,000 From: EPA 2011

37 Costs & Benefits of the CAA Cases prevented (2020) Adult mortality particles 230,000 Infant mortality particles 280 Mortality ozone 7100 Chronic bronchitis 75,000 Acute myocardial infarction 200,000 Asthma exacerbation 2,400,000 Emergency room visits 120,000 Lost school days 5,400,000 Lost work days 17,000,000 From: EPA 2011

Costs & Benefits of the CAA 1990-2020 Cases prevented (2020) Adult mortality particles 230,000 Infant mortality particles 280 From: EPA 2011 Mortality ozone 7100 Chronic bronchitis 75,000 Costs:

38 Costs & Benefits of the CAA Cases prevented (2020) Adult mortality particles 230,000 Infant mortality particles 280 From: EPA 2011 Mortality ozone 7100 Chronic bronchitis 75,000 Costs: equipment and operations Benefits: avoided deaths and disease (avoided health-care costs). Estimates for the value of a life are challenging: lost wages $7 - $9 million Acute myocardial infarction 200,000 Asthma exacerbation 2,400,000 Emergency room visits 120,000 Lost school days 5,400,000 Lost work days 17,000,000

39 Risk Communication Communicate with stakeholders about levels of health and environmental risk, including: the significance of health and environmental risks decisions, actions, or policies to control the risks. In general, we think of risk = toxicity * exposure), but the public may have a different view: Alternatively: Risk = Hazard and Outrage Or: Risk = Hazard and Values/Emotions From WHO Report on Risk Communication by Sue Lang, Lorna Fewtrell and Jamie Bartram iwachap14.pdf

40 Challenge: Dealing with Diverse Stakeholders Engineers and Toxicologists - 1 in 1 million risk of dying from cancer Regulators - this level of emissions will not contribute to significant deterioration of air quality Public - Is this safe for my children to play on the playground located within a mile of the refinery?

41 Challenge: risk is qualitative Risk estimates are based on models with inherent uncertainty and a variety of assumptions. Particularly challenging for rare and potentially high-impact events. Risk assessment depends on judgement, from scoping the analysis, selecting endpoints, to estimating exposure.

42 Challenge: risk is qualitative Risk estimates are based on models with inherent uncertainty and a variety of assumptions. Particularly challenging for rare and potentially high-impact events. Everyone (even an engineer) is wrong sometimes. Risk assessment depends on judgement, from scoping the analysis, selecting endpoints, to estimating exposure.

43 Communication Strategies Credibility. Engage early and build trust, limit outrage factor. Context. Your context should confirm your message. Try to engage media as an ally. Content. Your message must be meaningful and relevant to your audience. Clarity. Use analogies that are clear. The broader your audience, the simpler your message. Consistency. Focus on repetition with variation. Channels. Different audiences require different target media. Let audience know where to get additional information. Accessibility. Don t make it difficult to participate/access information. Offer the ability to meet in person if possible. Avoid overstatements

44 Communication Strategies Credibility. Engage early and build trust, limit outrage factor. Context. Your context should confirm your message. Try to engage media as an ally. Content. Your message must be meaningful and relevant to your audience. Clarity. Use analogies that are clear. The broader your audience, the simpler your message. Consistency. Focus on repetition with variation. Channels. Different audiences require different target media. Let audience know where to get additional information. Accessibility. Don t make it difficult to participate/access information. Offer the ability to meet in person if possible. Avoid overstatements People selectively listen to your message.

45 Communication Strategies Credibility. Engage early and build trust, limit outrage factor. Context. Your context should confirm your message. Try to engage media as an ally. Content. Your message must be meaningful and relevant to your audience. Clarity. Use analogies that are clear. The broader your audience, the simpler your message. Consistency. Focus on repetition with variation. Channels. Different audiences require different target media. Let audience know where to get additional information. Accessibility. Don t make it difficult to participate/access information. Offer the ability to meet in person if possible. Avoid overstatements People selectively listen to your message. Remaining silent can be a very risky strategy.

46 Choice of Words Negative connotation or confusing PhD pharmotoxicologist government abbreviations, jargon Positive connotation qualified, expert third party 8th grade reading level FCC, Title V permit conservative estimate

47 Choice of Words Negative connotation or confusing PhD pharmotoxicologist government abbreviations, jargon FCC, Title V permit Positive connotation qualified, expert third party 8th grade reading level Refinery process, air regulation conservative estimate

48 Choice of Words Negative connotation or confusing PhD pharmotoxicologist government abbreviations, jargon FCC, Title V permit conservative estimate Positive connotation qualified, expert third party 8th grade reading level Refinery process, air regulation Less than xyz, independent, objective, unbiased

49 Using Graphics Do a preflight with stakeholders/ sample audience. Label all axes and objects. Start the axes with zero if possible. Provide text explanations.

50 Using Graphics Do a preflight with stakeholders/ sample audience. Label all axes and objects. Start the axes with zero if possible. Provide text explanations. Meet in person when possible

51 Choosing your Messenger Source More trustworthy Health professional 1 Consumer organizations 2 Independent scientists 3 Government 4 Industry 5 From WHO Report on Risk Communication by Sue Lang, Lorna Fewtrell and Jamie Bartram iwachap14.pdf

Risk of Becoming a News Story Likelihood of becoming a major news story increases if the following are prominent: Questions of blame Alleged secrets and/or attempted

3 million fine and move its facility to move to Tooele Potential for widespread hazard Strong visual impact (picture of injured, black cloud of smoke) Links to sex

52 Risk of Becoming a News Story Likelihood of becoming a major news story increases if the following are prominent: Questions of blame Alleged secrets and/or attempted cover ups Human interest angle, i.e., heroes, villains, victims Links to high-profile issues or personalities Conflict Does the story foreshadow further problems Stericycle $2.3 million fine and move its facility to move to Tooele Potential for widespread hazard Strong visual impact (picture of injured, black cloud of smoke) Links to sex or a crime From WHO Report on Risk Communication by Sue Lang, Lorna Fewtrell and Jamie Bartram iwachap14.pdf

53 Supplementary Slides

54 Typical stakeholders Government (federal, state, city and county organizations) Subject matter experts (scientists engineers) Environmental groups Unions and groups concerned with worker health Community organizations Business and professional organizations (manufacturers association, chamber of commerce, etc.)

55 Goals of Engaging Stakeholders Build: Trust Understanding Don t wait until you have a crisis on your hands Credibility Satisfaction Anticipate concerns, be prepared for an event. From WHO Report on Risk Communication by Sue Lang, Lorna Fewtrell and Jamie Bartram iwachap14.pdf

56 Risk Assessment and Policy Section 812 of the Clean Air Act Requires EPA to assess the costs and benefits associated with the Clean Air Act, including: estimating the hazards associated with air pollutants regulated under the CAA using dose-response curves to estimate health effects using exposure estimates to determine the health impacts characterize uncertainties perform a cost-benefit analysis

57 Permissible Exposure Limit (PEL) OSHA regulation for workplace exposure PELs are designed to protect workers against the health effects of exposure to hazardous substances. PELs are regulatory limits on the amount or concentration of a substance in the air. They may also contain a skin designation. OSHA PELs are based on an 8-hour time weighted average exposure. Permissible exposure limits (PELs) are addressed in specific standards for the general industry, shipyard employment, and the construction industry.

58 Threshold Limit Values AIGH - is a level to which it is believed a worker can be exposed day after day for a working lifetime without adverse health effects Often seen on MSDS, gives an indication of toxicity. TLV is an estimate based on the known toxicity in humans or animals of a given chemical substance Changes over time Recommended

59 MSDSs Material safety data sheets provide workers and emergency personnel with procedures for handling substance in a safe manner (i.e., use, disposal, PPE) Chemical, physical, and toxicological properties (bp, mp, toxicity, reactivity, health effects, etc.) OSHA requires that MSDSs are available to employees for potentially harmful substances handled in the workplace. MSDSs must also be available to local fire departments and emergency planning officials.

60 Sandman on Fracturing Pluses, minuses and tradeoffs Can you think of any pluses, minuses, or concerns? Strategy for industry selling valid pluses; rebutting invalid minuses; and acknowledging valid minuses.

Risk Assessment and 09/13/07. Learning Objectives. Nature of Risk. Risk Assessment and Environmental Policy. Gene Schroder, PhD

Risk Assessment and 09/13/07. Learning Objectives. Nature of Risk. Risk Assessment and Environmental Policy. Gene Schroder, PhD Risk Assessment and Environmental Policy Risk Assessment and Environmental Policy Gene Schroder, PhD the dichotomy that exist between the perceptions of the public and the experts on which risks are important