TECHNICAL ASSESSMENT OF RISKS

Three technical workgroups were primarily responsible for evaluating the potential threats and assessing their risks to human health, ecosystems, and quality-of-life. Each of the three groups developed specific frameworks to use in gathering information about the potential threats.

HUMAN HEALTH ASSESSMENT

The National Research Council has taken the lead in developing the human health risk assessment methodology currently accepted as the model. This methodology includes four steps: 1) gathering data; 2) assessing exposure potential; 3) identifying how people may respond to a specified dose of the chemical of interest; and 4) characterizing the risk based on the information gathered in steps 1-3. This risk assessment model is mainly for assessing the probability of harm from specific chemicals. As such, it has limited application for comparing risks from general environmental threats, although the human health group did use it as a basis for developing their outline, which follows.

In evaluating the hazards or severity of human health effects from exposure to environmental threats in Ohio, the Human Health Workgroup identified the types of health effects potentially associated with the threat. These effects can include cancer or non-cancer effects and can be acute or chronic. When there is evidence of chemicals being associated with a potential threat, this was noted by the workgroup. For example, studies have shown that benzene is a carcinogen and mobile sources emit benzene into the atmosphere. People can inhale benzene, so the most common human health pathway is inhalation, rather than ingestion or absorption through the skin.

The Human Health Workgroup focused on identifying the potential for Ohioans to be exposed to the threats. In doing so, they made estimates of the size of Ohio's population that may be at risk to exposure. Where possible, special populations, such as children or the elderly, were identified if the threat poses a greater risk to them. Some of the threats are localized and distinctions among both geography and urban/rural differences were noted.

In an effort to identify further research needs, the members of the Human Health Workgroup identified specific sources of Ohio data. In an effort to make the limitations of the assessment clear, the workgroup noted the assumptions made in the existing research on which their evaluations were based.

Volunteers in the Human Health Workgroup focused on finding Ohio data regarding the potential threats using the outline below as guidance for writing reports. The availability of Ohio data constrained the research efforts, however the group did develop reports that ultimately serve as the foundation for most of the human health-oriented information in this report. The group also rated the human health risks using the reports and their professional judgment and presented their evaluations to the PAG as advice on the human health risks.

Human Health Outline 

I. 	Introduction

II. 	Hazards/Severity
     	A.  Types of Health Effects (cancer, non-cancer; chronic, acute)	
     	B.  Hazards (indicator chemicals, physical hazards such as fires)
     	C. Human health pathway (ingestion, inhalation, absorption)

III. 	Population
	A. Overall estimate (size of  Ohio's population exposed to hazards in II) 
        B. Special populations at risk from the hazards in II (children, the elderly, 
		asthmatics)
        C. Special geographic concerns (regions or communities in the state at special 
		risk from the hazards in II) (e.g. Southeastern Ohio, urban areas)

IV. 	Information/Discussion of Data Sources
        A.  Information on human exposure to health stressors (current state of the research   
                  identifying how humans are exposed)
	B. Dose-response (research identifying a link between dose of a chemical and  
		  human health response)
	C. Presence or absence of actual state data on incidence of illness or death 
		  (current data linking exposure to health risk in Ohio)        
	D. Level of conservatism in assumptions
	E. Information based mainly or only on animal model 
		  (presence of longitudinal human health studies or mainly laboratory studies)

V. Other Considerations
	A. Time imminence of threat(current, future or ongoing threat)
	B. Interconnectedness with other problems
	C. Reversibility of health threat
	D. Evidence of trend

ECOSYSTEM ASSESSMENT

Ecological risk assessment methods generally are not as well-developed as human health risk assessment methods, so the Ecosystem Workgroup faced a challenge in developing a framework for their research. As the Human Health Workgroup did, the Ecosystem Workgroup agreed to attempt to gather Ohio data relative to how Ohio's ecosystems have been affected by the potential environmental threats. Once again, as with the human health assessment, the availability of Ohio data was a limiting factor. The ecosystem framework is depicted below.

The Ecosystem Workgroup took a different approach than the Human Health Workgroup in attempting to specifically quantify the ecosystem risks on numerical scales. The scales resulted in scores for each of the potential threats and these scores were used in the group's rating of the ecosystem risks. 

Ecosystem Outline

I.   	General Overview
      
A. 	Background/Introduction of Activity

B. 	Definitions of Technical Terms

II.  Stressor Discussion

A.	Intensity.  A measure of the severity or magnitude on the health of the 
	ecosystem: 1 = non-lethal effects on individual organisms only; 2 = loss of  
	individual organisms; 3 = non-lethal effects on whole populations; 4 = loss or 
	exclusion of populations; and 5 = complete destruction of ecosystem.

B. 	Extent. The percentage of the ecosystem that is affected by the activity: 
	1 = less than 1% of ecosystem affected; 2 = 1-5% of ecosystem affected; 
	3 = 5-10% of ecosystem affected; 4 = 10-50% of ecosystem affected; and 
	5 = 50-	100% of ecosystem affected

 C. 	Reversibility. A measure of how long it will take the ecosystem to recover 
	from the effect of the stressor: 1=less than one year; 2=1-5 years; 3=5-20 years; 
	4=20-70 years; and 5 = unrecoverable (greater than 70 years)

 D. 	Uncertainty. A measure of the evidence that the effect will occur: 
	1= no direct evidence that effect will be produced; 2 = effect is possible 
	based on understood biological principals; 3 = effect is probably based on 
	experience with similar situations; 4 = some effects have been measured; 
	5 = effect documented to occur.

III. Level of Confidence 

The level of confidence scale is the opposite of the other scales (the higher the level 
of confidence, the more confident the researcher is about the information). The scale 
runs from 5 = no confidence to 1 = high confidence.

QUALITY-OF-LIFE ASSESSMENT

Even more than the ecological assessment, assessing quality-of-life risks is not based on an accepted model. The Quality-of-Life Workgroup faced a challenge not only in developing a framework to organize their research, but a real challenge in finding data to support their assessment of quality-of-life risks. The group focused on the six general criteria described below.

CRITERIA CATAGORY IMPACTS
Peace of Mind Safety,happiness,and health
Sense of Community Neighborhoods, personal growth and responsibility
Economic Impact Meeting one's needs, personal goal achievement, actual/projected costs, external costs, achievability
Aesthetics Visibility, noise, odors, and visual impacts
Fairness Sense of equity, environmental justice, number of affected persons, severity of effects on subpopulations, property owners rights
Future Generations Availability of substitutes, reversibility of effects, sustainability
Recreation Access to recreational lands, passive and active opportunities, quality of recreational environment, opportunities for solitude

In reviewing the criteria, it is clear that finding Ohio data that quantifies the impacts of potential threats on such factors as peace of mind or future generations is not easy. For this reason, the quality-of-life assessment was the most subjective and qualitative component of the technical analysis, although professional judgment did influence the other analysis as well. The Quality-of-Life Workgroup was instrumental in developing and compiling the environmental statistics and indicators found in Chapter 14 of the State of the Environment Report. As the other workgroups did, the Quality-of-life Workgroup ranked risks to quality-of-life in Ohio.

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