The Alliance for Chemical Awareness

ACA's Screening Level Evaluation Process
ACA has drafted a process for evaluating screening level exposure with the basic elements shown in the following outline. The ACA recognizes that there are many considerations that must be a part of this decisionmaking process, and these may vary significantly from one situation to another. These will certainly need further discussion and elaboration as the HPV program moves forward, in cooperation with sponsors and other stakeholders.

1. Understanding how a specific chemical flows through commerce. ...from chemical manufacturing, through distribution, handling, processing, end products, and release to the environment.

2. Determining the key routes by which a chemical might reach the public or the environment, including:

3. Estimating key exposures, using available predictive models and/or direct observations such as monitoring data. This step may also include assessing the potential for aggregate exposures (where an individual or the environment might be exposed simultaneously to the same chemical through several pathways). Consistent with the screening-level nature of the evaluation, work is focused on estimating key exposures for the above routes, based on predictive models and/or available direct observations (e.g., monitoring data). Where appropriate, the results from individual routes of exposure can also be used to estimate aggregate exposures for multi-purpose/multi-use chemicals.

4. Comparing exposures to relevant hazard data. The comparison of exposure to hazards may involve, for example, estimating margins of exposure (i.e., the ratio of exposure to a threshold for adverse effects). Such a calculation is often used as a surrogate for the potential of a chemical to cause harm.

5. Evaluating whether a chemical is sufficiently studied, or there is a need for further action. This typically involves a weight-of-evidence approach that takes into account the uncertainties associated with both the hazard and exposure analysis, severity of the potential harm, reliability of numerical estimates, etc... Four basic options are included:

Consultants
Disclaimer: Mention of specific consultants and consulting organizations is not intended to imply an endorsement of their use by the Alliance for Chemical Awareness nor is it intended to be considered a complete listing of consultants or consulting organizations. Persons considering use of a particular consultant or consulting organization, whether on this list or not, needs to conduct their own investigation of the technical merits and other factors associated with that consultant or consulting organization.

In addition to possible use of the above Internet Mailing Lists, the Web sites, membership directories, and journals of key professional societies are useful resources. These societies include the International Society of Exposure Analysis (ISEA: www.iseaweb.org/) and the Society for Risk Analysis (SRA: www.sra.org/).

Also, RiskWorld (www.riskworld.com) has an "Consultants, Environment, Health & Safety" section, ToxicologyOnline.com is a Web site with a Business Directory section listing some consultants, and the Consultants Alley (www.consultantsonline.org/gateway.htm) has an "Environmental Consultants" section.

Further, trade associations and professional colleagues may be able to share the names of consultants and consulting companies they have used or considered. For example, some possible consultants and consulting companies include (see disclaimer above, and consultants not currently listed should feel free to contact the Alliance for Chemical Awareness to be listed below):

Finally, the following book may be of interest (also available via the World Wide Web as part of Gale Business Resources' GaleNet at http://www.galenet.com/:

American Chemistry Council (formerly the Chemical Manufacturers Association)

In the summer of 1997, as part of the planning for the ACC Long-Range Research Initiative (LRI), State of the Science (STOTS) White Papers were prepared to identify the issues and the research needs associated with exposure assessment and other topics. In the fall of 1997, a large workshop of scientists was assembled in Research Triangle Park, NC for the expressed purpose of outlining the State of the Science (STOTS) program. As part of this effort, two polls of the member-companies were conducted to rate and rank the most important research issues impacting the chemical industry. In both polls understanding and quantifying the actual levels of chemical exposure to humans in the real world was ranked as the top issue.

Following the implied mandate from these polls, the Human Health Exposure Assessment Technical Implementation Panel (HHEA TIP) was formed in 1998. The goal from the beginning was to assemble a diverse group of exposure assessment professionals from different backgrounds and organizations. All the members bring experience in real life exposure and risk assessments to chemicals used in agriculture, consumer products, occupational, and public settings. In order to assure an open and diversified process, participants external to the chemical industry were also identified and added to the TIP. These included members from U.S. EPA, universities, Chemical Industry Institute of Toxicology (CIIT), and independent consultants in the exposure assessment field. At least one member has ties to the environmental activist community along with being both an outstanding scientist and an active environmentalist. In order to move the program forward three outstanding consultants with expertise in complimentary areas of exposure assessment were initially added to the TIP as full members and, as of late 2000, are still available "as needed" for specific TIP efforts relevant to their individual areas of expertise .

To get the TIP started in the right direction, two workshops were organized to solicit feedback from ACC member companies and from scientific experts in exposure assessment. For the first workshop, conducted in the fall of 1998, representatives from all ACC member companies were invited to come share the needs and concerns they had in the area of exposure assessment. Three areas were identified as the highest priorities for research:

MICROENVIRONMENTAL MODELING
DEMOGRAPHICS and DATABASES
DERMAL AND ORAL BIOAVAILABILITY
This workshop was followed in the spring of 1999 with a second workshop where more than 30 experts, actively engaged in exposure assessment research, were invited to identify specific research topics that could be selected for the research program. The workshop provided an excellent sounding board and technical discussion, but only partially narrowed the possible range of topics that the research program could address. In fact, the discussions added even more potential topics for consideration. Unable to identify a short list of research needs, the group came to the following conclusions:

The science of human exposure assessment is currently inadequate for cost-effective risk-based health evaluations.
There is no overall scoping vision available to define human exposure assessment research needs.
Research needs appear to be much larger than the amount of money being allocated.
Prioritization is absolutely necessary to render the most value in the shortest time.

Then, after two days of discussion, the experts unanimously recommended that the TIP commission and publish critical review papers on the current status of the science in four topic areas that would identify and prioritize gaps for further research:

1. Microenvironmental Models 2. Exposure Demographics 3. Dermal and Oral Availability 4. Comprehensive Chemical Exposure Model

The Exposure TIP followed the advice of the scientific experts and prepared and distributed Requests for Proposals (RFPs) for the first three topics at the end of 1999. Contracts for the first three were let in the spring of 2000 with completion in early 2001. An RFP for the fourth topic was distributed for bid in May, 2000 and was awarded in late 2000. The TIP will use the output from these projects to form the basis for how the TIP moves forward for at least the next three years, including the formulation and prioritization of the TIP's research plan.

Also, some other projects have been identified that are clearly worthwhile, and they are being funded in the context of the Research Management Plan as developed by the SST. These are projects that rate a high priority in fulfilling the mission of the TIP, which is:

Identify, facilitate, and communicate generic research that will characterize people's exposure to chemicals and raise the confidence and lower the uncertainty for quantitative estimates of exposure associated with potential human health effects to chemicals.

The projects currently being funded include :

Study of Worker Soil Ingestion by Dr. Ed Calabrese (University of Massachusetts).
Joint funding with the European Chemical Industry Council (CEFIC) to improve the EASE model.

The American Chemistry Council public Web site is: www.americanchemistry.com

American Crop Protection Association (ACPA)

Organized in 1933, ACPA is the not-for-profit trade organization representing the major manufacturers, formulators and distributors of crop protection and pest control products, including biotechnology products with crop production and protection characteristics. ACPA member companies produce, sell and distribute virtually all the active compounds used in crop protection chemicals registered for use in the United States. The ACPA Web site is: www.acpa.org/

(The late) American Industrial Health Council (AIHC)

AIHC's Exposure Assessment's Program Team Exposure's Initiative in early 2000 developed a case study set. The purpose was to prepare aggregate human exposure estimates and risk assessments for a set of five High Production Volume (HPV) chemicals, and to demonstrate the scope of available exposure information from chemical producers and users. The five compounds were selected to represent a variety of chemical types, product applications, exposure routes, and processes.

American Industrial Hygiene Association's (AIHA) Risk Assessment Committee

The American Industrial Hygiene Association Risk Assessment Committee was formed to further AIHA's national presence in risk assessment and to promote the growth and development of risk assessment expertise within the industrial hygiene profession. The committee's goal is to assemble, evaluate, and disseminate information on risk assessment issues, positions, science, and technology to industrial hygienists and other interested groups. The risk assessment committee sponsors symposiums, forums, and professional development courses to further educate and inform interested parties on the latest risk assessment methodology. The AIHA web site is: www.aiha.org/committe/risk.html.

Chemical Specialties Manufacturers Association (CSMA)

CSMA's Residential Exposure Joint Venture Project has a novel survey instrument for collecting temporal product use information. The current orientation is on pesticide products.

Health and Environmental Risk Assessment (HERA)

Initiative of AISE (the European association of the cleaning, detergent, maintenance, and soap product industries) and CEFIC started in 1999. A goal is to demonstrate that targeted risk assessment provides relevant safety information on detergent ingredients and products to regulators and the public in a fast and effective way. Other goals are to contribute to risk-based approach in European Union (EU) chemicals legislation, and to serve as a pilot for targeted risk assessment in other sectors and/or geographies.

Non-Dietary Exposure Task Force (NDETF)

This is a U.S. Food Quality Protection Act- (FQPA-) related effort for pesticides, including: 1) regulatory strategy for registration and re-registration, 2) evaluation of toxicological data, 3) screening-level dietary exposures and risk assessments, 4) screening-level and refined (Monte Carlo) nondietary exposures/risk assessments for indoor and outdoor residential uses, 5) design and implementation of an exposure monitoring program in simulated residential environments to measure dislodgeable residues, dissipation of airborne levels over time, biomonitoring in adult volunteers exposed to treated surfaces through normal contact activities, and a variety of satellite studies (e.g., collection of time-activity data for children), and 6) development of aggregate risk estimates.

Organisation for Economic Co-operation and Development's (OECD's) Work on Chemical Risk Management ("preventing, controlling, and reducing risks posed by chemicals"). Web site URL:

http://www.oecd.org/ehs/risk.htm
"The ultimate aim of the testing and assessment of chemicals is to prevent or manage undue risks. The core objective of OECD's work on risk management is to support Member countries' efforts to develop national policies and actions, and, where appropriate, to develop and implement international risk management measures. In support of this objective, the OECD Risk Management Programme focuses on two areas: (1) developing methods and technical tools that can be used by OECD and Member countries to enhance their current risk management programmes; and (2) identifying specific chemical exposures of concern in Member countries and evaluating possible risk management opportunities."

Of key interest to ACA efforts is OECD's "Providing Tools to Screen out Chemicals Harmful to Man and the Environment during the Research and Development Stage" effort. Quoting from OECD's Web site, "The aim of this initiative is to help identify, during a company's development stage when new chemicals are designed, those products that may pose a risk to man or the environment. The results of this work should lead to a reduction in the number of problematic chemicals entering new chemical review programmes, and a reduction in expenditures by companies on products that may never enter the marketplace. The main objectives of this initiative are (1) the collection of information on models, tools and other analytical methods used for screening new chemicals; (2) indexing and analysing this material; and (3) publishing the results on the Internet along with links to tools that are available on-line." This collection of information is in progress, and the results will be reviewed to help insure all useful exposure assessment software programs are included in the ACA's Web site collection, with appropriate links provided to OECD and non-OECD Web site information.

Outdoor Residential Exposure Task Force (ORETF)

The Outdoor Residential Exposure Task Force (ORETF) is a consortium of 33 member companies that have joined in response to a data call-in on exposure information for individuals reentering residential lawns that have been treated with pesticides. Its objectives include developing generic data to evaluate human exposures resulting from pesticide use on residential turf (mixer/loader and applicator exposure, and re-entry exposure to treated turf). Another objective is to determine exposures to pesticides used in home vegetable gardens and ornamentals. An example of an ORETF sponsored project is one to assess human activities on residential lawns with respect to incorporation of time-activity data for assessing post-application exposures to residential turf chemicals. Stanford University exposure experts have conducted videotaping to quantify the frequency and duration of specific time-activity data for children, including frequency of contact with surfaces and frequency of hand-to-mouth activities for assessing incidental oral ingestion exposures. The object of this effort is to develop a protocol for specific structured exercise or activity regimens on turf to simulate the contact with treated turf for each specific age group, which can then be used as a basis for exposure assessment. Other ORETF activities include analysis of pesticide turf-to-skin transfer factors, measurement of dermal and inhalation exposures to home pesticides during use, and the collection of survey information on the residential use and application of outdoor pesticides.