To start your own free subscription to Rachel's,
send a blank Email to: firstname.lastname@example.org
RACHEL'S ENVIRONMENT & HEALTH NEWS #810
Feb. 3, 2005
Published March 24, 2005
Human Exposure and Health Hazards - Pt. 1
by Anne Steinemann*
United States environmental regulations, intended to protect human
health, generally fail to address major sources of pollutants that
endanger human health. These sources are surprisingly close to us and
within our control, such as consumer products and building materials
that we use within our homes, workplaces, schools, and other indoor
environments. Even though these indoor sources account for nearly 90%
of our pollutant exposure, they are virtually unregulated by existing
laws. Even pollutant levels found in typical homes, if found outdoors,
would often violate federal environmental standards.
This article examines the importance of human exposure as a way to
understand and reduce effects of pollutants on human health. Results
from exposure studies challenge traditional thinking about pollutant
hazards, and reveal deficiencies in our patchwork of laws. And results
from epidemiological studies, showing increases in exposure-related
diseases, underscore the need for new protections. Because we cannot
rely solely on regulations to protect us, and because health effects
from exposures can develop insidiously, greater efforts and innovative
policies are needed to reduce and prevent significant exposures before
Pollutant Exposure Studies: Surprising Results
Numerous studies on personal exposure to pollutants have revealed some
startling results (Wallace, 1987, 1991, 1993; CDC, 2001, 2003; EWG,
We are regularly exposed to many toxic chemicals and carry them in our
bodies, as evidenced by samples of human blood, breath, hair, tissue,
and body fluids.
Most of our exposures to these chemicals are not from sources
traditionally regulated, such as remote waste sites and factories.
Rather, the primary sources are close to us: within our indoor
environments, and the personal activities, products, and materials
inside those environments.
Of more than several hundred pollutants regulated by federal laws, all
but a few are higher indoors than outdoors, due to indoor sources.
The sources of these pollutants are largely unregulated -- meaning
that our environmental regulations, designed to protect and promote
human health, are missing major sources of health risks.
The public is generally unaware of these types of everyday exposures,
their health consequences, and the relatively simple and cost-
effective actions that could reduce health risks.
Exposure Science: Measuring Pollutants that Affect Humans
The science of human exposure emphasizes an important but often
overlooked fact: The pollutants that affect human health are those
that come in contact with humans (Ott, 1985). In this way, exposure
science differs from traditional approaches to environmental
management. Instead of identifying a pollutant source and then trying
to trace emissions through the environment to see who or what might be
affected, exposure science starts with the receptor of those
pollutants -- humans. It identifies and measures the pollutants that
have reached humans, and then traces the pollutants back to their
sources. If a goal of environmental regulations is to protect and
promote human health, then we need to address not only the pollutant
sources but also the receptors.
Advances in the science of exposure assessment have enabled
researchers to measure, with great accuracy, the types,
concentrations, durations, and locations of human exposure to
environmental pollutants. These advances are technological, such as
the use of highly sensitive analytic instruments and portable exposure
monitors, and methodological, such as the use of sophisticated
probability sampling designs in large-scale field studies (Ott and
In the 1980s and 1990s, the U.S. Environmental Protection Agency (EPA)
and other researchers conducted the landmark TEAM (total exposure
assessment methodology) studies that measured personal exposures to
pollutants. These studies monitored more than 3,000 participants, in
18 U.S. urban and suburban cities and one Canadian province, for
exposure to volatile organic compounds (VOCs) (Wallace, 1987; Wallace
et al., 1991; Wallace, 1993), pesticides (Immerman and Schaum, 1990;
Whitmore et al., 1994), carbon monoxide (Akland et al., 1985),
particles (Ozkaynak et al., 1996a,b; Pellizzari et al., 1993),
phthalates (plasticizers) and polycyclic aromatic compounds (PAHs)
(Sheldon et al., 1993), among other pollutants. The participants
carried around personal exposure monitors that indicated what, how
much, and where pollutants were affecting them. In addition, the VOC
and CO studies measured breath levels of 2000 participants to detect
the chemicals in their bodies (Wallace et al., 1986; Wallace et al.,
These studies produced a compelling finding: Most of our exposure to
pollutants occurs indoors, and from products that we choose to use.
This result contradicted conventional thinking, and conventional
regulation, that focus on outdoor sources of emissions rather than
indoor and personal sources of exposures.
What and where are these pollutant sources? Studies identified the
** consumer products, such as air fresheners, deodorizers, cleansers,
disinfectants, personal care products, laundry supplies, moth
repellants, cosmetics, dry-cleaned clothes, solvents, and pesticides.
** building materials and furnishings, such as paints, varnishes,
adhesives, solvents, carpets, vinyl flooring, pressed wood products,
and combustion appliances.
** individual activities, such as bathing and washing in chlorinated
water, burning firewood and candles, refueling an automobile tank, and
Specific results include the following.
** VOC exposures indoors are typically 5 to 50 times higher than
outdoors, even in cities with relatively high levels of outdoor
pollution and heavy industry. New buildings often contain VOC levels
that are hundreds of times higher than outdoor levels (Sheldon et al.,
1988b; Wallace 2001). Common VOCs cause both acute and chronic health
effects, ranging from sensory irritation and headaches, to
neurological damage and cancer (Pierson et al., 1990; Otto et al.,
1990, NIH, 2003).
** Fragranced and scented products represent significant sources of
human exposure to toxic VOCs (Wallace et al, 1986, Wallace et al,
1988); specifically, synthetic fragrances that are found in numerous
consumer products , such as air fresheners, deodorizers, laundry and
dishwashing detergents, chlorine bleach, dryer sheets, and personal
care products such as shampoo, soap, lotions, hairspray, after-shave,
nail polish and remover (EPA 1989b; Sack and Steele, 1992; Cooper et
al., 1992). More than 95% of chemicals used in fragrances are
synthetic compounds derived from petroleum, including benzene
derivatives, aldehydes and many other known toxics and sensitizers
capable of causing cancer, birth defects, central nervous system
disorders and allergic reactions (USHR, 1986; NIH, 2003).
** Pesticide levels can be 5 to 10 or more times higher indoors than
outdoors, even though some pesticides are used only outdoors (Whitmore
et al., 1994). Reasons are that pesticides used outdoors, such as
termiticides, can seep indoors or be tracked inside by shoes; plus,
pesticides can persist much longer indoors where they are protected
from degradation. In addition, past applications of pesticides can
persist in the environment and in human bodies for decades after the
initial application. For instance, the pesticide
dichlorodiphenyltrichloroethane (DDT), which was banned in 1972, was
nonetheless found in carpets of 25% of 362 Midwestern homes (Camann et
al., 2000). In addition, polycyclic aromatic compound concentrations
found in carpet dust of 89% of these homes were more than seven times
the Superfund preliminary remediation goal for outdoor soil. This
implies that an average urban infant, consuming an average of 100 mg.
of dust containing 100 nanograms of benzo(a)pyrene a day, could be
exposed to an amount equivalent to smoking 2.8 cigarettes a day (Ott
and Roberts, 1998).
Partly influenced by the TEAM Study findings, several national and
regional task forces attempted to compare a wide selection of
environmental risks. The consensus was that the risk from indoor air
pollution and consumer products was far greater than most of the other
risk factors surveyed, including hazardous waste sites and outdoor air
pollution (EPA 1987, 1988a, 1989a; Omenn, 1997).
The U.S. Centers for Disease Control and Prevention (CDC) recently
conducted two nationwide assessments of human exposure to toxic
chemicals in air, water, food, soil, dust, and other media (such as
consumer products). The First National Report on Human Exposure to
Environmental Chemicals (CDC, 2001) presented exposure data for 27
chemicals (lead, mercury, cadmium, and other metals; metabolites of
organophosphate pesticides; cotinine; and phthalates). The Second
National Report (CDC, 2003) included these 27 chemicals and added 89
more, including polycyclic aromatic hydrocarbons; dioxins, furans, and
coplanar polychlorinated biphenyls (PCBs); non-coplanar PCBs;
phytoestrogens; organophosphate, organochlorine, and carbamate
pesticides; herbicides; pest repellants; and disinfectants.
Results showed some success in dealing with prior problems, such as
exposures to lead and environmental tobacco smoke. But they also
revealed new problems. One is exposure to phthalates, which virtually
all Americans now carry in their bodies. Phthalates are found in
numerous consumer products such as soft plastics, pesticides,
pharmaceuticals, lotion, children's toys, adhesives, detergents,
lubricants, food packaging, soap, shampoo, hairspray, nail polish, and
products made from polyvinyl chloride (PVC). Levels of phthalates were
highest in children and women of reproductive age, posing risks of
developmental and reproductive abnormalities, such as infertility,
precocious thelarche (onset of breast development before age eight in
girls), sperm damage, and birth defects (Raloff, 2000; NTS, 2000;
CERHR, 2000). Another is the prevalence of pesticides and the levels
of pesticides, especially in children. Metabolites of the pesticide
chlorpyrifos were nearly twice as high in children (age 6-11) than as
in adults. Metabolites of the organochlorine pesticide DDT were
clearly measurable in young adults ages 12 to 19, even though they
were born after the U.S. ban (CDC, 2003). [For a report on known and
potential health effects of chemicals in these CDC studies, see PSR
A recent exposure study, led by Mount Sinai School of Medicine in New
York, in collaboration with the Environmental Working Group and
Commonweal (EWG, 2003) evaluated nine adult subjects, none of who work
with chemicals, and all of whom were regarded as leading healthy
lives. The study found 167 industrial compounds (average of 91
compounds) in the blood and urine of these subjects, including
breakdown products from organochlorine and organophosphate pesticides,
polychlorinated biphenyls, dioxins, furans, and phthalates. These
chemicals are associated with cancer, brain damage, hormonal
disruption, birth defects, developmental abnormalities, reproductive
system defects, and immune system damage (EWG, 2003; NIH, 2003). Among
the chemicals tested, the most prevalent were 77 semivolatile and
volatile organic chemicals, present in common consumer products,
solvents, cleaners, and paints. None of these 77 compounds was tested
in the CDC studies, and each of them was found in at least one subject
in this study.
Next week: What are the health consequences of these chemicals in our
bodies, and what might we do about them?
* Anne Steinemann holds the title of Professor in the Department of
Civil & Environmental Engineering, and in the School of Public
Affairs, at the University of Washington in Seattle, where she is also
director of the Center for Water and Watershed Studies. This article
is a slightly modified version of "Human exposure, health hazards, and
environmental regulations," Environmental Impact Assessment Review
Vol. 24 (2004), pgs. 695-710.
References for Part 1
Camann D, Colt J, Teitelbaum S, Rudel R, Hart R, Gammon M. Pesticide
and PAH distributions in House Dust from Seven Areas of the USA, Paper
570 presented at SETAC 2000, Nashville, TN, November 16, 2000.
(CDC) Centers for Disease Control and Prevention. First National
Report on Human Exposure to Environmental Chemicals. 2001
(CDC) Centers for Disease Control and Prevention. Second National
Report on Human Exposure to Environmental Chemicals. 2003
(CERHR) Center for the Evaluation of Risks to Human Reproduction.
National Toxicology Program Center for the Evaluation of Risks to
Human Reproduction. Available online at
Cooper SD, Raymer JH, Pellizzari ED, Thomas KW, Castillo NP, Maewall
S. Polar Organic Compounds in Fragrances of Consumer Products. Final
Report, Contract 68-02-4544, U.S. EPA, Research Triangle Park, NC,
June 19, 1992.
(EPA) U.S. Environmental Protection Agency. Unfinished Business: A
Comparative Assessment of Environmental Problems. Volume I. Overview.
US Environmental Protection Agency. Washington, DC. NTIS #
(EPA) Future Risk: Research Strategies for the 1990s. US Environmental
Protection Agency. Washington, DC. 1988a.
(EPA) Comparing Risks and Setting Environmental Priorities: Overview
of Three Regional Projects. US Environmental Protections Agency.
Washington, DC. 1989a.
(EPA) Indoor air pollutants from household sources. EPA 600/X-89-164.
Environmental Monitoring Systems Laboratory. Las Vegas, NV. 1989b.
(EWG) Environmental Working Group. Body Burden: The Pollution in
People. Washington, D.C. http://www.ewg.org/reports/bodyburden 2003
Immerman, F. W. and Schaum, J. L. Nonoccupational Pesticide Exposure
Study: Final Report, EPA/600-3-90-003. U.S. Environmental Protection
Agency, Washington, DC, 1990.
(NIH) National Institutes of Health. Household Products Database,
Material Safety Data Sheets,
(NTS) National Toxicology Program. Center for the Evaluation of Risks
to Human Reproduction, Expert Panel Review of Phthalates, July 14,
2000, available at http://- ntp-
Omenn, G. Report on the Presidential/Congressional Commission on Risk
Assessment and Risk Management. Volume 1 Framework for Environmental
Health Risk Management; Volume 2, Risk Assessment and Risk Management
in Regulatory Decision-Making. 1997.
Ott WR. Total Human Exposure: An Emerging Science Focuses on Humans as
Receptors of Environmental Pollution, Environmental Science &
Technology 19:880-886, 1985.
Ott WR, Roberts JW. Everyday Exposure to Toxic Pollutants. Scientific
American 278:2, pp. 72-77, 1998.
Ott WR, Roberts JW, Steinemann A, Repace J, Gilbert SG, Moschandreas
DJ, Corsi RL. The Proposed Human Exposure Reduction Act. 2002.
Otto D, Molhave L, Rose G, Hudnell HK, House D, Neurobehavioral and
sensory irritant effects of controlled exposure to a complex mixture
of volatile organic compounds. Neurotoxicoloty and Teratology. 12:
Ozkaynak H, Xue J, Weker R, Butler D, Koutrakis P. and Spengler J. The
Particle TEAM (PTEAM) Study: Analysis of the Data. Volume 3. Research
Triangle Park, NC, EPA/600/R-95/098. 1996a.
Ozkaynak H., Xue J, Spengler JD, Wallace LA, Pellizzari ED, Jenkins P.
Personal Exposure to Airborne Particles and Metals: Results from the
Particle TEAM Study in Riverside, CA. J. Exposure Analysis and
Environmental Epidemiology 6:57-78, 1996b.
Pellizzari ED, Thomas KW, Clayton CA, Whitmore RW, Shores RC, Zelon
HS, Perritt RL. Particle Total Exposure Assessment Methodology
(PTEAM): Riverside, California Pilot Study. Vol. 1. Project Summary.
EPA/600/SR-93/050. Research Triangle Park, NC. NTIS # PB 93-166957.
(PSR) Physicians for Social Responsibility. Bearing the Burden: Health
Implications of Environmental Pollutants in Our Bodies, 2003
Raloff, J. Girls may face risks from phthalates, Science News, Vol.
158, September 9, pg. 165, 2000.
Sack TM, Steele DH, Hammerstrom K, Remmers J. A Survey of Household
Products for Volatile Organic Compounds, Atmospheric Environment, vol.
26A, No. 6, pp. 1063-1070, 1992.
Sheldon L, Clayton A, Keever J., Perritt R, Whitaker D. PTEAM:
Monitoring of Phthalates and PAHs in Indoor and Outdoor Air Samples in
Riverside, California. Vol. 2. Air Resources Board, Research Division.
Sacramento, CA, 1993.
(USHR) U.S. House of Representatives. Neurotoxins: At Home and the
Workplace, Report by the Committee on Science and Technology, Report
99-827, Sept. 16, 1986.
Wallace LA. Assessing human exposure to volatile organic compounds, in
Spengler, J.D., McCarthy, J.F., and Samet, J. (eds.), Indoor Air
Quality Handbook, New York, McGraw-Hill, Chapter 33, 2001.
Wallace LA. Comparison of risks from outdoor and indoor exposure to
toxic chemicals. Environmental Health Perspectives 95:7-13. 1991.
Wallace LA. The TEAM Study: Summary and Analysis: Volume I. U.S. EPA,
Washington, DC, EPA 600/6-87/002a, NTIS, PB 88-100060, 1987.
Wallace LA. A Decade of Studies of Human Exposure: What Have We
Learned. Risk Analysis 13:135-139, 1993.
Wallace LA, Jungers R, Sheldon L. Emission rates of volatile organic
compounds from building materials and surface coatings. Proc. of the
1987 EPA/APCA Symposium on Measurement of toxic and related air
contaminants. Research Triangle Park, NC, May 1987.
Wallace LA, Pellizzari ED, Hartwell T, Zelon H, Sparacino C, Perritt
R, Whitmore R. Concentrations of 20 Volatile Organic Compounds in the
Air and Drinking Water of 350 Residents of New Jersey Compared with
Concentrations in their Exhaled Breath. J Occup Med 28: 603-608, 1986.
Wallace LA, Pellizzari E, Wendel C. Total volatile organic
concentrations in 2700 personal, indoor, and outdoor air samples
collected in USEPA TEAM Studies. Indoor Air 4: 465-477, 1991.
Wallace LA, Thomas J, Mage D, Ott WR. Comparison of Breath CO, CO
Exposure, and Coburn Model Predictions in the U.S. EPA Washington-
Denver CO Study. Atmos Environ 22: 2183-93, 1988.
Whitmore RW, Immerman FW, Camann DE, Bond AE, and Lewis RG. Non-
Occupational Exposure to Pesticides for Residents of Two U.S. Cities,
Archives of Environmental Contamination and Toxicology, 26(1): 47-59,
RACHEL'S ENVIRONMENT & HEALTH NEWS
Environmental Research Foundation
P.O. Box 160
New Brunswick, N.J. 08903
Fax (732) 791-4603;
Subscriptions are free. To subscribe, send a blank Email to
The Rachel newsletter is also available free in Spanish; to subscribe,
send a blank Email to email@example.com.
BACK ISSUES IN ENGLISH AND SPANISH
Past issues are on the web at http://www.rachel.org in plain-text and
Permission to reprint Rachel's is hereby granted to everyone, though
we ask that you not change the contents and we ask that you give
In accordance with Title 17 U.S.C. Section 107 this material is
distributed without profit to those who have expressed a prior
interest in receiving it for research and educational purposes.
Some of this material may be copyrighted by others. We believe we are
making "fair use" of the material under Title 17, but if you choose to
use it for your own purposes, you will need to consider "fair use" in
your own case. --Peter Montague, editor