Also see http://www.halcyon.com/arthurhu/index/ahealth.htm#lead
/* Written 4:11 PM by firstname.lastname@example.org in igc:toxics.rachel */
/* ---------- "RACHEL: Lead & Behavior" ---------- */
TOXICS AFFECT BEHAVIOR
The toxic metal, lead, is associated with aggressive behavior,
delinquency, and attention disorders in boys between the ages of
7 and 11, according to a study by Herbert Needleman published in
1996 in the JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION
(JAMA). Aggressive behavior, delinquency and attention
disorders in youth are, themselves, predictors of criminal
behavior later in life. This is not the first study linking
lead exposure to behavioral disorders, but it is one of the most
Needleman's study examined 301 boys in public schools in
Pittsburgh, Pennsylvania, measuring the lead in their bones and
relating it to behaviors reported by the boys' teachers and
parents, and by the boys themselves. Boys with more lead in
their bones consistently had more reports of aggressive and
delinquent behavior, and problems paying attention. The boys'
behavior was measured at age 7 and again at age 11, and the
behavior of boys with more lead in their bones got worse as they
grew older; on the other hand, behavior did not change among boys
with less lead in their bones.
Aggressive behavior, delinquency, and attention disorders in boys
and young men are also associated with poverty, minority status,
and disorganized homes, so lead is not the only factor at work in
many cases. However, the 1996 Needleman study examined 9
variables in addition to lead (such as parent's socioeconomic
status, mother's age, presence or absence of a father in the
home, and so forth), to see if they might explain the boys'
behavior. The relationship between lead and behavior disorders
"These data argue that environmental lead exposure, a preventable
occurrence, should be included when considering the many factors
contributing to delinquent behavior," the authors of the study
What is remarkable is the degree to which environmental lead
exposure has been ignored in the past by people concerned about
the growing problem of aggressive, anti-social behavior in boys
and young men in the U.S. An estimated 20% of American children
now exhibit mental or behavioral problems. As early as 1943,
Randolph Byers and Elizabeth Lord examined 20 children who had
recovered from "mild lead poisoning in infancy." They reported
that none of the children had exhibited overt signs of lead
poisoning, yet the growth and development of their nervous
systems had been "seriously impaired." Among the 20 children
examined, only one had progressed satisfactorily in school.
Furthermore, many of the children were emotionally impaired as
well. Byers and Lord characterized the behavior of many of the
children as "unreliable impulsive behavior, cruel impulsive
behavior, short attention span, and the like." Three of the 20
children were expelled from school, one for setting fires,
another for repeatedly getting up and dancing on the desks, and a
third for sticking a fork into another child's face. In 1986,
Byers recalled that others in the group he had studied in 1943
had attacked teachers with knives and scissors. Byers's 1943
report should have set off alarm bells, but it didn't.
After the 1943 report, for the most part lead researchers ignored
the newly-revealed connection between lead, aggressive behavior
and impaired attention. Instead they went on to demonstrate
conclusively that intellectual power (as measured by IQ) was
consistently reduced by exposure to low levels of lead. For
every 10 microgram rise (in each deciliter of blood), there is a
6 point loss of IQ. [A deciliter is a 10th of a liter, and a
liter is about a quart.] Reduced IQ power can be measured when
lead is as low as 7 micrograms per deciliter of blood (7
ug/dl). In fact, there is no apparent threshold for this
effect: any amount of lead seems to diminish mental power in
children. Furthermore, brain damage from lead exposure
persists for many years; the IQ reduction caused by lead in
childhood is essentially permanent.
Nevertheless, some work on lead and behavioral disorders did
** In Virginia in 1975, researchers compared 67 lead-exposed
7-year-olds to 70 non-exposed children to see if lead exposure
was related to increased behavior problems in school.
Nineteen of the lead-exposed children were described as
"hyperactive, impulsive, and explosive, and as having frequent
temper tantrums." Only five among the non-exposed group were
described this way.
The group was re-evaluated a year later, emphasizing behavior in
the home. The examination of 8-year-olds revealed 14
lead-exposed children with "severe abnormalities," defined as
lying, stealing, running away, and setting fires, vs. six with
such abnormalities among the non-exposed group.
** In rural Tennessee in 1982, researchers asked teachers to
identify "problem children" among their students, using the
Walker Problem Behavior Identification Checklist, a screening
device designed for elementary school teachers to help them
identify troubled kids. Average lead levels in the hair of 26
"problem children" was nearly twice as high (11.6 ppm vs. 6.5
ppm) as in a control group of 29 students identified as not
** In Scotland in 1989, researchers showed that lead was related
to attention disorders and aggressive behavior (as reported by
parents and teachers) among a group of 501 students between the
ages of six and nine. These children had average (mean) blood
lead levels of 10.4 ug/dl.
** In Baltimore in 1992, blood lead levels among 201
African-American children aged two to five were compared to the
children's behavior as reported by their mothers on a well-known
standardized questionnaire (the Child Behavior Checklist, or
CBCL). Of these, 123 were in the "high exposure" group
(blood lead levels of 15 ug/dl, or more) and 78 were in a "low
exposure" group. The high-lead group consistently had more
maternal-reported troublesome behaviors. For example, 8.1% of
the high-lead group were "aggressive" vs. 1.4% in the low-lead
group. Mothers reported 4.1% of the high-lead children had
"destructive" behavior vs. no such behavior in the low-lead group.
** In New Zealand in 1993, researchers examined lead in the teeth
of 1265 children aged 6-8, compared to behavior of those children
as measured seven years later. They found a small but
consistent relationship between increasing lead and increasing
social adjustment problems in youngsters.
** In Boston in 1994, a study of 1782 children related the amount
of lead in their teeth to behavior in school (using the CBCL).
Problem behaviors increased systematically as lead levels in the
children's teeth increased.
In recent years, lead in the blood of Americans has diminished
substantially, because the government outlawed lead in gasoline
and lead in tinned cans used for food. The biggest reduction
has occurred among white children, but all populations have
benefitted to some extent. Nevertheless, in 1994, an estimated
1.7 million American children between the ages of one and five
(mostly African Americans living in large cities) had average
blood lead levels of 10 ug/dl or more, and a million children had
blood lead levels of 15 ug/dl or more. Among African American
children in large cities, 36.7% have blood lead levels above 10
ug/dl, and 17.0% of Mexican-American children in large cities
have similar levels of toxic lead in their blood.
In the mid-1970s, 40% of American children under age 5 had
average (mean) lead levels of 20 ug/dl or more. Among
African-American children in the mid-1970s, more than half had
blood-lead levels greater than 15 ug/dl. This is the
generation that is presently in its mid-20s. How is this
In 1993, 1.53 million Americans were in jail or prison --triple
the number that had been incarcerated in 1980. In 1980, one
in every 453 Americans was in state or federal prison; by 1993,
the number had risen to one in every 189. In 1993, the
incarceration rate among blacks was seven times as high as among
whites. Between 1990 and 1993, the number of drug offenders
increased dramatically by 55,500, but the number of violent
offenders grew even more rapidly (by 82,100). In 1994, the
prison/jail population increased at the rate of 1600 each week
and almost 1200 (75%) of these new inmates were black or hispanic.
It seems possible that the observed connection between
brain-damaging lead and destructive behavior explains a portion
of these increases.
Prevention is the key. The main source of the toxic lead in
children today is dust and soil, but the source of the lead
in the dust and soil is lead-based paint coming out of older
buildings. The federal Centers for Disease Control (CDC) in
Atlanta has calculated the cost of removing all lead-based paint
from old buildings, along with the benefits that society would
realize from such a removal (reduced costs for medical care and
for special education, plus increased salaries that go with
higher IQs). According to CDC, American taxpayers would realize
a net profit of $28 billion by removing all lead-based paint.
Why then do you suppose Congress is delaying?
(National Writers Union, UAW Local 1981/AFL-CIO)
 Herbert L. Needleman and others, "Bone Lead Levels and
Delinquent Behavior," JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION
Vol. 275, No. 5 (February 7, 1996), pgs. 363-369. In the same
issue of JAMA, see the editorial: Terrie E. Moffitt, "Measuring
Children's Antisocial Behaviors," JOURNAL OF THE AMERICAN MEDICAL
ASSOCIATION Vol. 275, No. 5 (February 7, 1996), pgs. 403-404.
And see: B. Bower, "Excess lead linked to boys' delinquency,"
SCIENCE NEWS Vol. 149 (February 10, 1996), pg. 86.
 Needleman and others, cited above in note 1, citing D.P.
Farrington, "Childhood aggression and adult violence," in D.J.
Pepper and K. Rubin, editors, THE DEVELOPMENT AND TREATMENT OF
CHILDHOOD AGGRESSION (Hillsdale, N.J.: Lawrence Erlbaum
Associates, 1991), pgs. 189-197, which we have not seen. And
see: D.R. Offord and others, "Delinquency and Hyperactivity," The
JOURNAL OF NERVOUS AND MENTAL DISEASE Vol. 167, No. 12 (1979),
pgs. 734-741. And see: Thomas M. Achenbach and others, "Six-Year
Predictors of Problems in a National Sample of Children and
Youth. II. Signs of Disturbance," JOURNAL OF THE AMERICAN ACADEMY
OF CHILD AND ADOLESCENT PSYCHIATRY Vol. 34, No. 4 (April 1995),
 David Bellinger and others, "Pre-and Postnatal Lead Exposure
and Behavior Problems in School-Aged Children," ENVIRONMENTAL
RESEARCH Vol. 66 (1994), pgs. 12-30.
 Randolph K. Byers and Elizabeth E. Lord, "Late Effects of
Lead Poisoning on Mental Development," AMERICAN JOURNAL OF
DISEASES OF CHILDREN Vol. 66, No. 5 (November 1943), pgs. 471-494.
 Randolph K. Byers, unpublished data described by Needleman,
cited above in footnote 1.
 John F. Rosen, "Health Effects of Lead at Low Exposure
Levels," AMERICAN JOURNAL OF DISEASES OF CHILDREN Vol. 146
(November 1992), pgs. 1278-1281.
 John F. Rosen, "Effects of Low Levels of Lead Exposure,"
SCIENCE Vol. 256 (April 17, 1992), pg. 294.
 Herbert L. Needleman and others, "Deficits in Psychologic and
Classroom Performance of Children with Elevated Dentine Lead
Levels," NEW ENGLAND JOURNAL OF MEDICINE Vol. 300, No. 13 (March
29, 1979), pgs. 689-695. And see: Joel Schwartz, "Low-Level Lead
Exposure and Children's IQ: A Meta-analysis and Search for a
Threshold," ENVIRONMENTAL RESEARCH Vol. 65 (1994), pgs. 42-55.
And see: Herbert L. Needleman and Constantine A. Gastonis,
"Low-Level Exposure and the IQ of Children," JOURNAL OF THE
AMERICAN MEDICAL ASSOCIATION Vol. 263, No. 5 (February 2, 1990),
 Herbert L. Needleman and others, "The Long-term Effects of
Exposure to Low Doses of Lead in Childhood," NEW ENGLAND JOURNAL
OF MEDICINE Vol. 322, No. 2 (1990), pgs. 83-88.
 The few studies examining lead and behavior in the period
1944-1980 are reviewed in Herbert L. Needleman and Philip J.
Landrigan, "The Health Effects of Low Level Exposure to Lead,"
ANNUAL REVIEW OF PUBLIC HEALTH Vol. 2 (1981), pgs. 277-298.
 Brigitte de la Burde and McLin S. Choate, "Early
Asymptomatic Lead Exposure and Development at School Age,"
JOURNAL OF PEDIATRICS Vol. 87, No. 4 (1975), pgs. 638-642.
 Mike Marlowe and John Errera, "Low Lead Levels and Behavior
Problems in Children," BEHAVIORAL DISORDERS Vol. 7 (1982), pgs.
 G.O.B. Thomson and others, "Blood-Lead Levels and
Children's Behaviour--Results from the Edinburgh Lead Study,"
JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY Vol. 30, No. 4 (1989)
 William G. Sciarillo and others, "Lead Exposure and Child
Behavior," AMERICAN JOURNAL OF PUBLIC HEALTH Vol. 82, No. 10
(October 1992), pgs. 1356-1360. 17 (April 23, 1987), pgs.
 David M. Fergusson and others, "Early Dentine Lead Levels
and Subsequent Cognitive and Behavioural Development," JOURNAL OF
CHILD PSYCHOLOGY AND PSYCHIATRY Vol. 34, No. 2 (1993), pgs.
 James L. Pirkle and others, "The Decline in Blood Lead
Levels in the United States," JOURNAL OF THE AMERICAN MEDICAL
ASSOCIATION Vol. 272, No. 4 (July 27, 1994), pgs. 284-291.
 Debra J. Brody and others, "Blood Lead Levels in the U.S.
Population," JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION Vol.
272, No. 4 (July 27, 1994), pgs. 277-283.
 David Bellinger and others, "Longitudinal Analyses of
Prenatal and Postnatal Lead Exposure and Early Cognitive
Development," NEW ENGLAND JOURNAL OF MEDICINE Vol. 316, No. 17
(April 23, 1987), pgs. 1037-1043.
 Fox Butterfield, "More in U.S. Are in Prisons, Report Says,"
NEW YORK TIMES August 10, 1995, pg. A14.
 Allen J. Beck and Darrell K. Gilliard, "Prisoners in 1994,"
BUREAU OF JUSTICE STATISTICS BULLETIN [NCJ-151654], August, 1995,
 Bernard Weiss, "Intersections of Psychiatry and Toxicology,"
INTERNATIONAL JOURNAL OF MENTAL HEALTH Vol. 14, No. 3 (1985),
 Evan Charney and others, "Increased Lead Absorption in Inner
City Children: Where Does the Lead Come From?" PEDIATRICS Vol.
65, No. 2 (February 1980), pgs. 226-231.
 Brian L. Gulson and others, "Paint as a source of
recontamination of houses in urban environments and its role in
maintaining elevated blood leads in children," SCIENCE OF THE
TOTAL ENVIRONMENT Vol. 164 (1995), pgs. 221-235.
 Herbert L. Needleman and Richard J. Jackson, "Lead Toxicity
in the 21st Century: Will We Still Be Treating It?" PEDIATRICS
Vol. 89, No. 4 (April 1992), pgs. 678-680, citing a 1991 CDC
Descriptor terms: lead; herbert needleman; behavior;
criminality; delinquency; heavy metals; IQ; central nervous
system; attention disorders; aggressiveness;
Environmental Research Foundation provides this electronic
version of RACHEL'S ENVIRONMENT & HEALTH WEEKLY free of charge
even though it costs our organization considerable time and
money to produce it. We would like to continue to provide this
service free. You could help by making a tax-deductible
contribution (anything you can afford, whether $5.00 or
$500.00). Please send your contribution to: Environmental
Research Foundation, P.O. Box 5036, Annapolis, MD 21403-7036.
--Peter Montague, Editor
Date sent: Tue, 18 Feb 97 18:14:21 -0500
From: Peter Montague
Subject: Re: (Fwd) [PNEWS_FORUM] RACHEL: Lead & Behavior
Send reply to: email@example.com
Sure. Thanks for asking. --Peter M.
> content-length: 16319
> I'd like to include this article on my web page under health, I'll keep the plug
> for contributions at the bottom of the article, OK?