EEH 2005 Conference Highlights

The EEH 2005 conference was held during October 5-7, 2005 in Atlanta, Georgia USA. The conference was attended by over 150 delegates converging to Atlanta from four continents of the world. In this web page we provide you the highlights of the EEH 2005 conference held in Atlanta, GA, USA

OVERVIEW

The First International Conference on Environmental Exposure and Health has been held in Atlanta, organized by Georgia Tech and the Wessex Institute of Technology. The Conference Co-chairmen were Professor Mustafa Aral from Georgia Tech; Professor Carlos A. Brebbia from WIT; Dr Morris Maslia of Centre for Disease Control (CDC); and Dr Thomas Sinks, Acting Director of the National Centre for Environmental Health of CDC.

The conference was very successful and brought together scientists from many different institutions, ranging from health specialists to social and physical scientists together with engineers. They evaluated the current issues in exposure and epidemiology and chartered further directions and needs in the field.

OPENING ADDRESS

The meeting was organized by Prof. Mustafa Aral who thanked all participants, including authors and members of the International Scientific Advisory Committee. He was particularly grateful to CDC for their support of the conference and the number of excellent presentations put forward by delegates from that institution. Mustafa was complimentary of the excellent work carried out by WIT and in particular the professionalism of the Institute’s Conference Division as demonstrated by the work done by Katie Banham, the Secretary in charge of the meeting.

Carlos Brebbia then referred to the success of the conferences as demonstrated by the number and quality of the papers presented at the meeting. He stressed that that success was in great part due to the work of Mustafa, who ensured an excellent American participation. Carlos also referred to the quality of the conference book and the fact that WIT always tries to ensure that as many papers as possible are published in the proceedings after due processing. He then explained the work carried out at WIT, including that of its Conference Division, emphasizing the major advances of the last two years or so.

Three important keynote addresses opened the conference, the first given by Dr Thomas Sinks, acting Director of the National Centre for Environmental Health, Agency for Toxic Substances and Disease Registry at the Centre for Disease Control and Prevention.

KEYNOTE ADDRESS BY DR. THOMAS SINKS

Dr. Sinks has held several leadership roles at CDC. As the Acting Deputy Director for Program for NCEH/ATSDR, Dr Sinks was the principal deputy director on scientific and program issues for the agency and he assisted the director in the agency’s day-to-day operations and long term strategies. He has been the Associate Director for Science (ADS), NCEH since 1995 and became the lead scientist for both NCEH and ATSDR in October, 2003. As the ADS his responsibilities include assuring the quality, integrity and development of science throughout NCEH/ATSDR. He was the Acting Associate Director for Chemical and Radiological Terrorism Preparedness and Emergency Response from February through to October 2003. Dr Sinks helped establish and coordinate CDC’s preparedness and response activities relating to a chemical or radiological emergency and natural disasters. Dr Sinks served as the Acting Director, Division of Birth Defects, Child Development, Disability and Health from October 1999 until November 2000 when it became the National Center for Birth Defects and Developmental Disabilities. In 1997, Dr Sinks served as Acting Chief, Air Pollution and Respiratory Health. In 1991-1994, Dr Sinks was the Chief, Health Studies Branch and conducted epidemiologic investigations of hypervitaminosis D in Massachusetts, a key poisoning in Jamaica, optic neuropathy in Cuba, heat-wave related deaths in Philadelphia, and the 1992 bombing of the World Trade Center.

Dr. Sinks began his CDC career in 1985 as an Epidemic Intelligence Service Officer assigned to the National Institute for Occupational Safety and Health (NIOSH). He remained at NIOSH until 1991 and was involved in investigations of respiratory disease among Hawaiian sugarcane workers and the causes of mortality of electric capacitor builders exposed to PCBs.

Dr. Sinks received his Bachelor of Science degree from the Tulane University, New Orleans, LA in 1973. He received his Masters of Science and Doctor of Philosophy degrees in 1982 and 1985 respectively from Ohio State University.

The National Center for Environmental Health, Dr Sinks explained, deals with:

• Prevention program

• Measurement of people's exposure to chemicals

• Investigating disease outbreaks

• Preparing emergency response programs

They carry out health investigations and prepare toxicology reports. Dr Sinks discovered the problem of human response to environmental chemicals, asbestos and more recently cases like Hurricane Katrina. The chemical exposure program tries to answer which chemicals are harmful, how many people are exposed and in which way. Based on these guidelines, priorities can be set for health research purposes.

Other problems of interest are the effects of materials such as lead and cadmium. The first is routinely monitored and its influence continues to diminish. Cadmium instead is still causing concern and its persistence is possibly due to smoking. Mercury loads in humans are also regularly monitored, specially because of its importance for the female population. More recently the Agency has started to provide bio-monitoring for new types of contaminants.

Current asbestos studies include vermiculite which can contain a high proportion of asbestos fibers. The contamination in regions mining vermiculite affects not only the workers but also the general population.

The most recent work of CDC was related to Hurricane Katrina.  It included preparedness and planning; pre-impact and impact scenarios; response and recovery.  Personnel of CDC have participated in many activities related to the Hurricane, working on site with different authorities.

Dr Sinks’ office deals with information regarding diseases, Environmental Health problems, occupational safety, mental health and communication.

KEYNOTE ADDRESS BY DR. FRANK HEARL

The second keynote address was the Modern Problems posed by Occupational health in the 21st Century, by Dr. Frank Hearl.

Frank Hearl is presently the Chief of Staff of the National Institute for Occupational Safety and Health (NIOSH) working there at the office of the Director in Washington DC. Frank has been with NIOSH for over 31 years, serving in past capacities as Deputy Director for the Division of Respiratory Disease Studies, and as Head of the Environmental Investigations Branch in Morgantown, West Virginia. From 1996 to 2002, Frank was Team Leader for the NIOSH National Occupational Research Agenda (NORA) Mixed Exposure Team. He is co-author of many papers, and presentations. Dr Hearl has participated in sever important international projects, including the study of dust exposure of Chinese workers for several years and mining surveillance assistance in South Africa.

Frank referred to the current problems of workers exposed to multiple agents, either as intrinsically complex mixtures or as separate simultaneous exposures to a variety of substances or stressors. Some intrinsically complex mixtures routinely encountered in occupational settings are diesel exhausts, welding fumes, coke oven emissions, and metal working fluids. Other workplace combinations that result in biological interactions are less obvious, such as the combined action of certain organic solvents and noise exposure, which results in hearing loss to an extent greater than would be predicted by either exposure alone. Although the regulatory agencies and consensus standard setting bodies have recognized the existence of combined effects from mixed chemical exposures, and have proposed dose-additivity formulas for adjusting an occupational exposure limit (OEL), in practice most exposures are regulated or controlled as if they occurred independent of any other substance exposures. Little information or guidance is available to assist practicing industrial hygienists for the application of a modified OEL to account for mixed exposures. Research is needed to provide a sound scientific basis to describe interactions, and to assist practitioners in applying appropriate algorithms for controlling exposures where antagonistic, additive or synergistic effects may be predicted and expected.

INVITED PRESENTATIONS

Other important  invited presentations were as follows:

Modeling personal and population exposures to environmental chemicals, by Dr. Thomas E. McKone, University of California School of Public Health and Lawrence Berkeley, National Laboratory.

This paper described a general framework for organizing and calculating multi-pathway exposure to environmental chemicals. There are complex links among ambient environmental media (air, water, soil, etc.) and the exposure media that eventually bring these chemicals into contact with humans. Exposures may be dominated by contacts with a single medium or may reflect concurrent contacts with multiple exposure media. Here the models that describe cumulative personal and population exposures to chemicals dispersed in multiple environmental media are evaluated. The magnitude and relative contribution of each exposure pathway must be considered in order to assess total human intake of a harmful substance and determine the best approach for more refined characterization of the exposure. The importance of including or excluding temporal and spatial variability of the exposure pathways that link individuals and populations to various sources of potential exposure is assessed. This evaluation is based on (a) overall uncertainty, (b) inter-individual variability, and (c) longitudinal variations both over short periods (weeks to months) and over longer term (life stages). The model evaluation reveals the importance of balancing among the competing needs for reliability, relevance for health studies and feasibility. Because exposure assessments are limited by uncertain models and limited opportunity for comparing the model to exposure measurements, an optimum strategy for increasing the reliability of exposure assessments is to merge models and data.

·        Development of cost-effective statistical sampling strategies and optimal design considerations for exposure assessment as part of the National Children’s Study, by Dr. Warren Strauss, Batrelle, USA

This paper describes a project to develop innovative statistical study design guidance for the acquisition of exposure data over time in a longitudinal study of children who participate in the National Children's Study (NCS). The NCS is intended to investigate environmental influences on children's health and development–including understanding any environmental exposures that may cause or exacerbate health impacts. Due to the large sample size and longitudinal nature of the Study, unique statistical issues arise that must be addressed before a cost-effective sampling design can be developed to gather the environmental and personal exposure data. A key issue for the NCS relates to obtaining enough samples to provide adequate statistical power to detect health effects attributable to environmental and personal exposures, while being cost-effective, minimizing participant burden, and staying within the study's overall budget. Relevant specific issues include identification of potential sources of bias and/or uncertainty in the exposure measures (non-response, subject burden, attrition, and measurement error); and strategies to address these issues, including the use of validation sampling techniques to obtain highly detailed measures on a carefully selected subset of the study population, while using less detailed (and presumably less expensive and less burdensome) measures across the entire NCS cohort. The utility of using these techniques for developing study protocols for the efficient (and unbiased) study of important relationships between exposure and health outcomes within the NCS was demonstrated by the speaker.

·        Exposure assessment concepts and considerations for community health Studies, by Dr. P. Barry Ryan, Emory University

Recently, exposure assessment has become much more quantitative with the exposures measured being much more highly correlated with outcome variables.  Improved exposure assessment methods have worked in conjunction with epidemiology to give a better understanding of the source-exposure-dose-effect continuum. Such methods range from relatively crude measures to much more sophisticated, and costly, methods. The focus was on community health investigations- investigations primarily in non-industrial settings where exposures may be relatively low, but are widespread. Methods not requiting environmental measurements such as and questionnaire data collection methods and assess their utility were discussed. Methods requiring field environmental measurements, including both microenvironmental approaches and personal monitoring represent the next level of sophistication. Biomonitoring methods that include measuring directly whether exposure occurs by analysis of biological samples for parent compounds and metabolites of the contaminant in question were also discussed.

Role of biomonitoring in exposure and community human health studies, by Dr. Larry Needham, NCEH, CDC

The three primary types of epidemiological health studies are longitudinal (cohort), case/control, and cross-sectional studies. Each of course requires an accurate assessment of exposure in order to link exposure and disease. Exposure issues however vary with the nature of the chemical being monitored. Chemicals can be readily classified as persistent and nonpersistent, considering both the environment and within the body. Exposure to persistent chemicals is ideally assessed by biomonitoring in a variety of biological matrices, the selection of which in part depends on the age range of the participants. On the other hand, exposure to nonpersistent chemicals may or may not be readily achievable. This issue was discussed in detail and a community health study involving dioxin exposure was described.

Measurement of Exposures to Air Pollutants, Metals and Pesticides, by Dr. Halûk Özkaynak, U.S. EPA National Exposure Research Laboratory, Research Triangle Park, NC, 27711

Estimating children’s health risks requires knowledge and understanding of routes and pathways of exposures to environmental agents of concern and information on concentrations of these chemicals in the relevant media or in personal air samples. The presentation summarized the primary methods that are used for environmental and personal samples for air pollutants, metals and pesticides. Exposures to particulates and gaseous pollutants could play a role in the development and exacerbation of asthma in children. At present, particulate concentrations in the air are typically collected by active sampling methods. Gaseous air pollutants can be collected with passive or active samplers. Passive samplers are usually the most suitable for personal monitoring, but they can also be used for microenvironmental (e.g., indoor) and fixed site outdoor monitoring. Exposures to certain toxics metals (e.g., lead, mercury) and pesticides have been associated with neurocognitive or neurodevelopmental effects on children. Particle-bound chemicals, including PAHs and other semi-volatile organics, can be collected on a filter followed by a suitable sorbent material. Dietary ingestion is often an important exposure route for most metals, although ingestion of water, ingestion of dusts and soils, and inhalation of particles containing metal, may be important for some metals at certain ages. Measurement of pesticide concentrations in the relevant environmental media requires a combination of techniques. Many pesticides, such as the organophosphate and carbamate insecticides, are semi-volatile and are readily detectable in indoor and personal air samples. The newer classes of pesticides, on the other hand (e.g., pyrethroids), are less volatile and thus air sampling is not the best choice for them. However, both persistent and non-persistent pesticides can be measured readily in the house dust samples. Because of typical hand-to-mouth activities of young children, dust is usually a significant medium of contaminant exposure for young children in the home environment. Diet is also a potentially significant pathway of exposure to pesticides for children. Collection and analysis of duplicate diet samples for pesticide residues is the method of choice for dietary exposure measurement. Other indirect methods, such as modeling dietary intake using food consumption surveys, are also employed in estimating dietary exposures of children.

Stochastic Air Quality Analysis, by Dr. V. P. Singh, Louisiana State University, Baton Rouge, USA

Air quality and human health are intimately connected. In many urban areas in the United States air quality becomes unacceptable several times a year. Ozone (O₃) is one of the most commonly used criteria for judging air quality. The ozone (O3) concentration arises from photochemical reactions between oxides of nitrogen and hydrocarbons in the presence of ultraviolet light. Higher ozone concentrations usually are often observed in industrial areas and the areas with high automobile emissions of nitrogen oxides and hydrocarbons. These areas therefore tend to have higher health problems. Thus, analysis of the ozone concentration is important. Five variables pertaining to the ozone concentration can be chosen for analysis: (1) the number of days the ozone concentration exceeding the national ambient air quality standard and design value in a given year; (2) the highest ozone reading in a given year; (3) the duration of an ozone exceedance; (4) time interval between ozone exceedences; and (5) trend over time of non-attainment parishes. These variables may be inter-related and may be stochastic in nature. In this study, a stochastic analysis of the ozone violation was investigated using the copula concept for Baton Rouge in Louisiana. Using this analysis, risk to human health was then analyzed. Dr. Singh summarized his work on Copula method and demonstrated its use in analytical evaluation exposure through air pathway.

CONFERENCE SESSIONS

A substantial number of other contributions were grouped in the following sessions:

• Environmental health and public policy

• Exposure modeling, measurement and assessment

• Environmental and occupational exposure

• Emerging water contaminants

• Indoor air quality and exposure

• Environmental impact and exposure

• Air exposure modeling and assessment

• Biomarkers in exposure studies

• Health risk analysis

• Exposure-dose reconstruction

• Chemical mixtures and exposure

• Site specific studies

• Children’s health and the environment in hazardous waste sites

• Exposure and health studies in the developing world

• Communicating social and environmental issues in exposure

CONFERENCE BANQUET

The conference dinner took place in a restaurant which offered a variety of dishes from different cuisines, ranging from Italian and French to Greek and Spanish, and of course, American. The excellent wines and champagne from the Napa Valley contributed to the unique occasion.

CLOSE OF CONFERENCE

Mustafa Aral closed the conference with an excellent presentation discussing the evolution of Environmental Management Paradigms from the time that resources were regarded as inexhaustible and to be exploited with a frontier mentality to the other side of the spectrum in which first radical and later select environmentalist ideas took hold. We are now, according to Mustafa, at a moment of sustainable environmental management. The question is if this new paradigm will work and the chances are that it will not. Mustafa stressed the need to define a new paradigm that looks to human health and the whole picture. Sustainable environmental management ought to lead to “management for sustainable populations”. This is specially important in view of the emergence of a large number of megacities and having to consider natural as well as forced disasters.

All disciplines, in Mustafa’s view, are required to come together as in the case of this conference and specialists from areas as diverse as social issues, public policies, basic sciences, engineering, media and others, to start working together. More barriers need to be broken, new rules established and a common language needs to emerge. This is indeed the main motivation for holding the Environmental Exposure and Health Meeting.

CONFERENCE PROCEEDINGS

The proceedings of Environmental Exposure and Health, 528 pp (ISBN: 1-84564-029-2) are available in hard back from WIT Press priced at £185/US$325/€277.50. Orders can be placed by telephone: +44 (0) 238 029 3223, fax: +44 (0) 238 029 2853, e-mail: marketing@witpress.com or via the WIT Press web site at www.witpress.com.

The proceedings of the EEH 2005 was published and distributed to the delegates during the conference. The full reference for this publication is given below:

Aral, MM, Brebbia, C, Maslia M and Sinks, T. (Eds) (2005) “Environmental exposure and Health,” Proceedings of the1st International Conference on Environmental Exposure and Health, Atlanta Ga. USA, WIT Press, 502p.

Please find below keynote, invited and conference closure presentations to bring you the highlights of the EEH 2005 conference:

• Dr. Tom Sinks (Keynote presentation - NCEH/CDC)

• Dr. Frank Hearl (Keynote presentation - NIOSH)

• Dr. Haluk Özkaynak (Invited presentation - National Exposure Research Laboratory, USEPA)

• Dr. Thomas E. McKone (Invited presentation - LBNL/UC Berkeley)

• Dr. Larry Needham (Invited presentation - NCEH/CDC)

• Dr. Barry Ryan (Invited presentation - Emory University)

• Dr. Warren Strauss (Invited Presentation - Battelle, USA)

• Dr. Vijay Singh (Invited presentation - Louisiana State University)

• Dr. Mustafa Aral (Conference closure presentation - MESL, Georgia Institute of Technology)

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