Insulation II & Panel Discussion

Risk is defined as the probability to cause harm.  Current assessments utilize the dose where noted observations or “hazard” occurs and determine a concentration-specific “risk” based either on generic statistics-based modeling using the assumption of a linear dose response or on known mode-of-action (MOA) principles.  However, the practice of risk assessment and the assumptions inherent within an assessment can be confusing to the general public.  Often a hazard is confused with a risk and chemical or product deselection may subsequently result.  Consequently, the question should be asked if a chemicals’ MOA is unknown should a predicted concentration be considered a “risk” or simply an “uncertainty.”  For formaldehyde, animal studies used to determine carcinogenic potential have reported that no tumors are produced other than what occur at the site of administration, i.e., nasal cancer in rats following inhalation exposure to sufficient doses of formaldehyde.  This only happens at doses that kill cells and cause mutations in less injured cells which can then divide leading to the formation of tumors.   The current cancer risk assessment generated by EPA predicts excess risk at levels below naturally occurring formaldehyde concentrations detected in rural ambient air.  Such a dichotomy does not appear to be supported by the science.  Or does it? 

Many other data are available for formaldehyde in rodents and humans that are instructive in completing an MOA.  Is there a wide concentration range by which these endpoints are recognized or do the effects related to formaldehyde exposure occur in a narrow concentration band?

This paper will examine the historic literature on formaldehyde, present new scientific information on the chemical conducted both in the US and the EU and will examine the dose at which effects are observed and how these relate to the MOA.

This paper will examine the modeling of the small chamber formaldehyde emission profile of fiberglass batt insulation on the indoor environmental quality of a typical residence. By placing fiber glass in series with other construction materials the impact is demonstrated to have a deminimis affect on indoor formaldehyde concentrations. The VERSAR model for predicting formaldehyde emission is utilized to predict concentrations over time. The typical building construction schedule is examined and correlated to depict the deminimis impact of insulation on formaldehyde exposure.

Most of the environmental impacts that occur stem from the life cycles of goods and services. These life cycles span the full chain of processes from raw materials acquisition through primary and secondary manufacturing, transportation of inputs to and from production, product installation, use, and maintenance; and finally, end-of-life.  Wastes, pollution, resource depletion, and their negative consequences, at any point in the life cycle, represent an un-discovered resource.  For example, energy use leads to emissions that lead to human mortality and morbidity, climate change, and so-on. Its use signals the possibility for cost-effective measures that can reduce it. An under-appreciated (and under-utilized) fact is that designers at any stage of any product life cycle have the ability to make changes which can harness some of these ubiquitous resources, for economic, environmental, and public health benefit. A series of case studies by the Harvard School of Public Health has estimated the public health and economic and environmental impacts of cost-effective residential insulation in the US. Results indicate that cost-effective measures have the potential to avoid, over a 50-year period, on the order of two million life-years worth of public health damages. This presentation will summarize the findings, describe the analysis methods, and illustrate in practical terms how designers at any point in product life cycles can make increasingly efficient use of emerging databases to do these analyses themselves, and re-design for economic, environmental, and public health benefit.