Encyclopedia of Public Health (S-Z)

423 Pages·2002·3.038 MB·English

by  Lester Breslow

PHvol4 5/22/03 3:24 PM Page 1
Encyclopedia of
Public Health
Editorial Board
EDITOR IN CHIEF
Lester Breslow, University of California at Los Angeles,
School of Public Health
ASSOCIATE EDITORS
Bernard D. Goldstein, Graduate School of Public
Health, University of Pittsburgh
Lawrence W. Green, Centers for Disease Control and
Prevention
C. William Keck, Akron, Ohio, Health Department
John M. Last, University of Ottawa
Michael McGinnis, The Robert Wood Johnson
Foundation
ii
PHvol4 5/22/03 3:24 PM Page 3
Encyclopedia of
Public Health
Edited by Lester Breslow
Volume 4
S-Z
Appendix
Index
Copyright © 2002 by Macmillan Reference USA, an imprint of the Gale Group
All rights reserved. No part of this book may be reproduced or transmitted in any
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the Publisher.
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Gale Group and Design is a trademark used herein under license.
Library of Congress Catalog in Publication Data
Encyclopedia of public health / edited by Lester Breslow.
p. cm.
Includes bibliographical references and index.
ISBN 0–02–865354–8 (set : hardcover : alk. paper) — ISBN 0–02–865350–5
(v. 1 : alk. paper) — ISBN 0–02–865351–3 (v. 2 : alk. paper) — ISBN 0–02–
865352-1 (v. 3 : alk. paper) — ISBN 0–02–865353–X (v. 4 : alk. paper)
1. Public health—Encyclopedias. I. Breslow, Lester.
RA423 .E53 2001
362.l’03—dc21 2002031501
Printed in the United States of America
10 9 8 7 6 5 4 3 2 1
S
SAFETY dating violence; court-based programs for victims
of domestic violence; mentoring; and parent
Safety consists of “attempts to minimize the risk of education.
injury, illness, or property damage from the haz-
Communities should also make efforts to as-
ards to which one may be exposed” (Edlin et al.
sure safe public places. Thriving communities need
1999, p. 522). Safety for one’s home, one’s com-
parks, downtown shopping areas, business dis-
munity, and oneself is best achieved through a
joint effort involving individuals, schools, law en- tricts, schools, and public-housing communities
forcement, and other private and public agencies. where residents can feel protected from the threat
of crime and violence. There are several ways to
Home safety can be improved by exterior create such places through joint efforts with gov-
lighting around doors and windows, secure locks ernment agencies, businesses, law enforcement,
that are consistently used, block watch programs,
and citizens’ groups. Poverty, discrimination, lack
and informing neighbors of unusual individuals or
of education, and lack of employment opportuni-
events. Internal home safety is optimized by light-
ties are important risk factors for violence and
ing on stairways, lack of clutter, and consistent
must be addressed as part of any comprehensive
maintenance of home and contents.
solution to the epidemic of violence in urban
communities. Strategies for reducing violence
The National Crime Prevention Council has
should reach children early in life, before violent
identified several strategies to improve commu-
nity safety. Community mobilization is the process beliefs and behavioral patterns can be adopted.
of bringing individuals together so that they can
A new concern for parents and teachers is the
jointly guard property, report suspicious behavior
concept of cybersafety. The Internet has many
to the police, combat criminality, and form a
sites devoted to pornography, hate literature and
spirit of community. Examples of community-
excessive violence, and parents and teachers need
mobilization efforts include neighborhood watch
to monitor the web sites that children visit. The
groups, mobilizing senior citizens as volunteers,
best defense for children is for adults to educate
business watch groups, and early warning arson
them about issues that can cause them harm.
prevention. These efforts are a cost-effective way
Parents and teachers should carefully select an on-
to combat crime and reduce fear.
line service that offers control features to block
Violence prevention at the local level recog- out different types of sites, and children should be
nizes the need to punish violent offenders, sup- taught to not give out personal information, to
port victims, and teach nonviolence. Strategies can never agree to meet anyone without their parent’s
include teaching conflict management, public dia- consent, and to never send a photo of themselves
logue, and dispute resolution; combating teen over the Internet to someone they do not know.
1057
SAFETY
The reduction of intentional (deliberate) and To continue the decrease in school criminality
nonintentional (accidental) injuries is the concern and hopefully lessen the incidents of school shoot-
of both individuals and communities. Such inju- ings/mass murders, the U.S. Department of Edu-
ries include nonfatal head injuries, nonfatal spinal cation and the U.S. Department of Justice (1998)
cord injuries, firearm-related injuries and deaths, recommend the following for schools to do the
motor vehicle-related injuries, poisonings, and following:
deaths from suffocation. Prevention strategies for
1. Provide strong administrative support for
unintentional injuries include the use of safety
assessing and enhancing school safety.
belts, child restraints, motorcycle and bicycle hel-
mets, graduated driver licensing, and functioning 2. Redesign the school facility to eliminate
smoke alarms in residences. dark, secluded, and unsupervised spaces.
Understanding the factors that cause injuries 3. Devise a system for reporting and analyz-
allows for development and implementation of ing violent and noncriminal incidents.
effective prevention interventions to improve safety.
4. Design an effective discipline policy.
Some interventions can reduce injuries from both
unintentional and violence-related causes. For in- 5. Build a partnership with local law
stance, efforts to promote proper storage of fire- enforcement.
arms in homes can help reduce the risk of uninten- 6. Enlist school security professionals in
tional shootings in the home. Higher taxes on designing and maintaining the school
alcoholic beverages are associated with lower death security system.
rates from motor vehicle crashes and lower rates
7. Train school staff in all aspects of violence
for some categories of violent crime, including rape.
prevention.
Women face special threats to their safety.
8. Provide all students access to school
Date rape (acquaintance rape) occurs when a date,
psychologists or counselors.
boyfriend, or someone that a woman knows forces
sexual relations. Women can help protect their 9. Provide crisis response services.
safety while dating by openly discussing sexual
10. Implement school-wide education and
expectations. Women also need to be very careful
training on avoiding and preventing
not to become intoxicated or be under the influ-
violence.
ence of any substance that will lessen their ability
to make rational decisions while on a date. 11. Use alternative school settings for educat-
ing violent and weapon-carrying students.
Although recent tragedies and mass murders
12. Create a climate of tolerance (address
at schools have led to the conclusion that schools
racism and discrimination).
are becoming less safe, it is important to remem-
ber that 90 percent of the schools in the United 13. Provide appropriate education services to
States are free of violent crimes and serious safety all students.
issues (U.S. Department of Education and the U.S.
14. Reach out to communities and businesses
Department of Justice, 1998). In recent years there
to improve the safety of students.
has been a decrease in criminality and the number
of children carrying weapons to school. Some of 15. Actively involve students in making deci-
the reasons for this change are due in part to sions about school policies and programs.
increases in school security measures, zero-tolerance
16. Prepare an annual report on school crime
policies, and the implementation of school vio-
and safety.
lence prevention programs (U.S. Department of
Education and the U.S. Department of Justice, Some specific measures that a school can initi-
1998). Children are more likely to be the victim of ate quickly are the following: “hiring security per-
a crime or seriously harmed in their own home or sonnel, installing security devices, conducting ran-
in the community than at school. Despite these dom inspections, and providing students/staff with
facts, children are more fearful of school today identification cards” (U.S. Department of Educa-
than what has historically been reported. tion and the U.S. Department of Justice 1998, p.
1058
SAFETY ASSESSMENT
25). With these continued efforts, schools can occur. It also relies on animal toxicology studies.
continue to be a safe place for America’s youth. The assumption made is that humans are more
sensitive to these chemicals than the most sensitive
KATHY AKPOM animal species tested.
TAMMY A. KING
Acute toxicity studies are used to determine
the potential for poisoning, as well as possible
(SEE ALSO: Behavioral Change; Community Organiza-
antidotes. The acute LD50 (that dose that is lethal
tion; Crime; Domestic Violence; Family Health;
to 50% of the animals tested) is seldom directly
Legislation and Regulation; Occupational Safety
extrapolated from animals to man, but many occu-
and Health; Street Violence; United States Consumer
pational exposure standards and categorizations
Product Safety Commission; Violence)
of household chemicals are based on the LD50.
Safety assessment for direct food additives, such as
BIBLIOGRAPHY colorants or flavors, is based on the no observable
effect level (NOEL) in laboratory animals, or on an
Eldin, G.; Golanty, E.; and Brown, K. M. (1999). Health
approximation of that level. The ADI is deter-
and Wellness, 6th edition. Sudbury, MA: Jones and
Bartlett. mined from the NOEL (with appropriate safety
factors) and is based on the percentage of any
National Crime Prevention Council (2000). Cybersafety
dietary component that contains the chemical, so
for Kids Online: A Parent’s Guide. Washington, DC:
that if a person consumes a kilogram of food per
Bureau of Justice Assistance, Office of Justice Pro-
day and the compound of interest is only found in
grams, U.S. Department of Justice. NCPC informa-
tion is available at http://www.ncpc.org. 10 percent of the food products generally con-
sumed, that 10 percent becomes the exposure
——— (2000). Date Rape Is a Power Trip. Washington,
maximum that is used in the calculations.
DC: Bureau of Justice Assistance, Office of Justice
Programs, U.S. Department of Justice.
Safety assessment for therapeutic agents is
——— (2000). Invest in Home Security. Washington, DC: also based on animal toxicity, but it is also a
Bureau of Justice Assistance, Office of Justice Pro- function of the doses to be used, the diseases to be
grams, U.S. Department of Justice. treated, and the conditions of the treated popula-
U.S. Department of Education and the U.S. Department tions. As an example, the safety assessment of an
of Justice (1998). Annual Report on School Safety. over-the-counter (OTC) drug is more stringent
(Pamphlet released by Richard W. Riley, Secretary of than for a drug to be used for the treatment of a
Education and Janet Reno, Attorney General.) life-threatening situation. A therapeutic index (TI)
U.S. Department of Health and Human Services (2000). is developed for almost all drugs and is based on
Health People 2010. Available at http://web.health. the ratio of the toxic dose to the efficacious dose:
gov/healthypeople/. The greater the ratio, the greater the margin of
safety in use of the drug. A drug being used for
cancer chemotherapy can have a greater toxicity
SAFETY ASSESSMENT and a much smaller TI than a drug for the com-
mon cold. A cancer patient may be in a life-
Safety assessment is the process that results in an threatening situation, but a doctor or nurse is
“acceptable daily intake” (ADI) of specific chemi- monitoring his or her signs and symptoms of
cals. Safety assessment has been carried out in the toxicity. In contrast, an individual may be taking
United States and much of the Western world uncontrolled amounts of a cold preparation and is
since the late nineteenth century. Since the 1950s probably not being monitored by a health profes-
it has become much more formalized in its use by sional. The other issue in this example is that there
regulatory agencies to incorporate animal toxicol- is a much larger consumer population for OTC
ogy studies and potential exposures. Safety assess- products than for chemotherapeutic products, and
ment starts with the underlying premise that expo- the risks of OTC drugs may not be as well appreci-
sure to a chemical, be it a drug, food additive, ated. Hence, the “involuntary” risk taker must be
cosmetics ingredients, or consumer product, will more protected.
1059
SAFETY FACTORS
Consumer products present a different chal- or dose limit and are not expressed as a probabil-
lenge for safety assessment. The assumption here ity, which cancer risk assessments are. Safety as-
is that the consumer of a household product will sessments are similar throughout the world.
ingest or touch the product, or inhale vapors from
MICHAEL GALLO
the product. The product is manufactured for
something other than consumption, and the pack-
aging has to be part of the safety assessment. For (SEE ALSO: In Vivo and In Vitro Testing; Risk
example, a household cleanser may be caustic and Assessment, Risk Management; Safety Factors;
highly oxidizing. This product will cause extreme Toxicology)
damage to tissues, and the risk is known from
animal studies or by analogy to other chemicals of
the same class. The only way to assure less risk to SAFETY FACTORS
the user is through strong, vivid, unequivocal la-
Safety factors have been used to protect the public
beling, and childproof packaging.
health since the advent of modern safety assess-
Pesticides present a special case in safety as- ment. Originally based on very little experimental
sessment. First, most pesticides are designed to data, the concept of safety factors was based on the
control and/or kill pests. By definition, pesticides, premise that humans are more sensitive to chemi-
especially insecticides, are moderately or highly cals and environmental agents than the most sensi-
toxic when compared to most other consumer tive laboratory animal. By the time of World War I,
products. The safety assessment and toxicology experimental evidence with laboratory animals
package for a pesticide depends on whether it is was being directly compared with findings in hu-
going to be registered as a crop chemical, a chemi- mans. It was evident that the original premise had
cal for ornamental flowers, a home-use pesticide, little basis in fact, but was still a prudent approach
or some other use. The crop chemicals, be they for public health. As novel organic molecules were
insecticides, herbicides, fungicides, or growth regu- being developed as drugs and insecticides in the
lators, complete a battery of tests from in vitro 1930s and 1940s, the concept of safety factors gave
through carcinogenicity. The logic being that con- scientists and regulators some comfort that the
sumers could be exposed to minute amounts of public was being protected. Actual data on safety
residues from application to the crops, and there factors is still incomplete.
must be a large margin of safety between potential
For many highly toxic compounds, humans
exposure and toxicity. Again, an ADI is established
are almost identical to laboratory animals in sensi-
based on the toxicity of the chemical, the NOEL,
tivity. However, there are startling examples, such
the shape of the dose-response curve, the amount
as thalidomide and some retinoic acid analogs,
of a particular crop in a food product, how much
where humans are much more sensitive than labo-
may be eaten or drunk, and the body weight or
ratory animals. Several attempts have been made
surface area of the consumer (children are special
to quantify the physiological and toxicological dif-
cases). This information allows the regulators to
ferences across species. For the basic physiological
establish an ADI expressed in milligrams (or
systems that are essential for all mammalian spe-
micrograms) of a chemical that can be consumed
cies, the responses to many classes of chemicals,
safely in a day. ADIs are also set for different drugs, and physical agents are similar.
durations of exposure, but usually for a greater
part of the lifetime. The basic assumptions underlying the use of
safety factors is that by using these factors the
Safety assessment differs from cancer risk as- public health is protected and special populations
sessment in several ways. Safety assessments are are also protected. Further assumptions hold that
for multiple endpoints, not just cancer, and can be humans are somewhere between 10 and 1,000
for multiple time points. Threshold limit values times more sensitive to some toxic agents than are
(TLVs) are examples of safety assessments that can animals, adults are less sensitive than children, and
be set for acute toxicity, eye irritation, or systemic the aged are more sensitive than younger individu-
toxicity. Safety assessments arrive at an exposure als. Hence, a safety assessment can be conducted
1060
SALMONELLOSIS
using the proper toxicological evaluation with multi- food additives, and others types of chemicals, pub-
ple species of animals to establish the NOEL (no lished a rich history of the rationale and use of
observable effect level) or its equivalent. The asses- safety factors.
sor can then use safety factors for species to spe-
MICHAEL GALLO
cies extrapolation (usually a factor of ten or more),
which involves multiplying the NOEL by a tenfold
factor for age differences, and perhaps a tenfold (SEE ALSO: Environmental Determinants of Health;
Risk Assessment, Risk Management; Safety Assess-
factor for special populations. Hypothetically if a
ment; Toxicology)
NOEL established for Chemical A at 1,000 milli-
grams per kilogram body weight of the laboratory
rat per day, the assessor could compute the safety
SAFETY STANDARDS
factors and conclude that a safe dose would be 1
milligram per kilogram per day. During the twentieth century many countries be-
gan to develop requirements for manufacturers
This is a simple case, and many other variables
and service industries to reduce high rates of
can be added. For an occupational exposure one
injury, illness, and fatality in both the working
might add a factor for hours worked compared to
environment and in consumer products. Led by
hours used in the tests. For an immunotoxic agent
professional organizations and by the United Na-
there might be a greater safety factor used for
tions, safety standards set criteria for the construc-
species or age comparison, particularly if children
tion of machinery to prevent injury to operators of
or the aged are exposed. The uncertainties sur-
the machines, and for the production of con-
rounding testing for adverse birth outcomes usu-
sumer products to avoid injury to purchasers.
ally result in the use of greater safety factors.
Through such standards, dramatic improvements
The rationale for additional safety factors for have occurred throughout the world in industrial
health and accident prevention. Not all countries
children has evolved over several years. Originally,
have well-developed or enforced standards, how-
children were looked on as small adults and their
ever, and standards continue to be refined and
physiological differences, especially the rapid de-
developed.
velopment and remarkable tissue and organ sys-
tems changes of children, were not given as much BARBARA TOEPPEN-SPRIGG
as attention as necessary. Recently, the emphasis
has been on understanding how seemingly modest
(SEE ALSO: Occupational Safety and Health; Preven-
or small changes in a developing system can per-
tion; Primary Prevention)
manently alter that system when it matures. Greater
care is now going into using safety factors for
children. More basic research is still necessary to SALMONELLOSIS
protect children, and until that work is completed
the prudent approach has been to increase the Salmonellosis is a common enteric disease caused
safety factors for children. by rod-shaped, gram-negative bacteria. The name
is derived from the American veterinary surgeon,
Safety factors are widely used by regulators
Daniel A. Salmon, who described Salmonella cholerae-
throughout the world. Some countries use safety
suis as the cause of hog cholera in 1885. Since then
factors for assessing the exposures to some car-
over 2,200 Salmonella serotypes have been de-
cinogens. The United States generally uses a quan- scribed; each is distinguished by its unique combi-
titative risk assessment (QRA) approach to car- nation of cell wall, flagella, and capsular antigens.
cinogens, but uses a modification of the original Many serotypes are further subdivided, usually for
safety factor approach for most other toxic end- epidemiological studies, by their sensitivity to stan-
points. Safety factors were used exclusively until dard sets of bacteriophages (phage typing), and
the late 1960s and early 1970s when the QRA DNA fingerprinting methods. Salmonella are found
methodologies were developed. The U.S. National in the intestinal tract of animals and birds, includ-
Academy of Sciences/National Research Council ing domestic species (e.g., cattle, poultry), wild
has, through its many studies on drinking water, animals, and pets. Most human infections are
1061