EXPERIENCE AND REASON-BRIEFLY RECORDED 783
A Spot Test for Detection
of Lead
in Paint
Lead poisoning is one of the most important
environmental health hazards
in
inner-citychil-dren today. The disorder almost always results
from the child eating chips of paint, putty, or
plaster containing toxic quantities of lead.
Identification of painted surfaces which contain dangerous quantities of lead is an extremely
important part of the household investigation
in any case of lead poisoning. Furthermore,
paint testimig is a valuable means of locating
potentially dangerous areas in homes where
there are small children. Window sills, walls,
and other interior surfaces are pointed out as
particularly common sources of lead.”
Hereto-fore, testing of paint samples by spectroscopic
methods has been tedious, expensive, and
re-quired that specimens be submitted to a
labo-ratory. A semiquantitative method suggested
by Kaplan and Shaull,3 while easier, still has
the limitation of requiring technical ability,
equipment, and dangerous chemicals. The
meth-od of testing herein proposed is simple,
inex-pensive, and specific, and can be performed in
the patient’s home. It involves the precipitation
of lead as an insoluble black sulfide through
the following reaction:
Pb + Na,S - PbS
METHOD
A solution of sodium sulfide of about 5 to 8%
is prepared. This solution must be kept tightly
covered to prevent loss of potency through
hy-drolysis, which releases volatile H,S. It is
con-veniently dispensed in 5 ml polyethylene
squeeze-dropper bottles. Sodium sulfide does
not attack the surface of these bottles. A label,
“Poison : Harmful to Eyes or if Swallowed” is
affixed. In this concentration there is no skin
irritation, but the characteristic odor of
hydro-gen sulfide may persist on one’s hands for a
half-hour. While the total amount of sodium
sulfide in this small bottle (250 to 400 mg) is
of low potetitial toxicity,4 it should nonetheless by kept out of the reach of young children.
The paint can be tested either in situ or as a
full-thickness chip of paint removed from the
surface of the wood or plaster. If testing is
done in situ, it is essential that all layers of
paint be exposed down to the bare surface by
making a diagonal cut with a sharp penknife.
If the paint is tested as a chip, a similar
diago-be wetted by the sodium sulfide solution. This
is essential since the deeper, older layers of
paint and particularly the primer coat may be
the only ones which contain lead. Paint which
has been more recently applied is less likely to
contain hazardous amounts of lead. All layers
should be inspected carefully for a color
change (Fig. 1
)
. Adequate lighting is mostim-portant for proper interpretation of the test,
particularly when evaluating dark colored or
soiled paints. At times a hand magnifying lens
is very useful.
SENSITIvITY
This is a qualitative reaction and the
inten-sity of the color change varies directly with the
amount of lead present. Over the past 2 years
in a lead paint screening program in Rochester,
over 200 homes have l)een inspected. When
the sodium sulfide testing method was
intro-duced, chips were taken to the laboratory and
examined with both sodium sulfide amid
spec-troscopic methods. A black color developed in
specimens proven to contain between 10 and
25% lead. However, quantitative
determina-tiomis on specimens of paint composed of many
layers may not yield an accurate comparisomi,
Fic. 1. Chip of paint with two layers. Top layer
(
toward camera ) has turned quite black. Under0.82.4 4
s
12 I784 TEST FOR LEAD
FIG. 2. Gradations of color changes in paint of known had content. Note light gray color has
ne-!(.I(JJ)(.(l vitli paint containing less than 1% lead.
since all layers of I)aimt are not necessarily
lead-containimig. For this reason, a specimen of
exterior white primer paiit of knowii
composi-tion was obtained from a local paint
mamiufac-turer. By calculation from the formula used fri production, the pain t contaimied approximately
22% lead
in
tIme wet state. A specimen was thendried and its lead content measured
quantita-tivelv. This resulted in a yield of 18% lead. As-suming the value to be approxiniatelv 20%, the
paint was diluted with another sample of white paint known to contain less than 1% lead. Paimit
of successive dilutions was then applied to
WOO(I surfaces, dried, and tested with the so-diurn sulfide solution. Small wooden samples
were pieced together and a comparator block
made
(
Fig. 2) . It can be seen that gradatiomisof light gray through dark gray to black are
oh-tamed and that at the lowest dilution of 0.8% a
faint gray color is present. Colors at the 15 to
20% range are dark enough to make it difficult
to approximate lead concentrations over this
amount.
SPECIFICITY
A host of other heavy metals may be fotmnd
in paimits. Those found in large quantity are
zinc, titanium, and barium, none of which form
black sulfides. Other metals are constituents of
pigmemits and occur in aniounts less thami 1%:
cadmium, chromium, cobalt, iron, manganese,
magnesium, mercury, molybdenum, and n’
Of these, black sulfides are formed by iron,
nickel, mercury, and molybdenum but the
quantities present are small enough to cause no
confusion. Copper also forms a black sulfide,
but its only use in paiiit is for its anti-fouling
properties. It would have no place in household
paints. Black paint may be difficult to
inter-pret, but is miot ordinarily made with lead.’
Care must be taken, however, in testing metal
surfaces covered with paint such as pipes, or
radiators simice the iron or copper may be
pre-cipitated.
DISCUSSION
Surveys made fri a number of U.S. cities
have demonstrated the prevalence of lead
painted1 household interiors to be as high as 50
to 70%. To cope with so prevalent a condition
as this, the use of expemisive methods that
re-quire transport of samples to a laboratory or
the use of other devices in situ may he out of
the reach of health departments or other
corn-munity groups. This method, however, when used as described herein, puts testing within
the reach of many people such as public health
nurses, community aids, and volunteers. A
comparator block such as shown in Figure 2 is
easily made and could be used as a standard if
extensive testing was plamined.
There are a number of other advantages
of-fered by the sodium sulfide spot test:
(
1)
The method is simple, inexpensive andinvolves a minimum of chemicals and
equip-ment. The small dropper bottle with its
tight-fittimig cap is easily carried in omie’s pocket or
the glove compartment of a car. The bottles
can be obtained from most pharmacies.
(2) Little training is mieeded in the
interpre-tation of the color change. Care must be taken
to test all layers of paint down to amid
includ-imig bare wood or plaster.
(
3) The testing can aiid should be done inthe home, particularly
in
areas accessible tochildren. Attemition should be paid to areas
where children have been observed to pick at
walls or windowsills. Loose chips of paimit on
the floor or on the ground outside should also
be tested.
(4) Testing may be done at the time
sun-faces are scraped and refinished. In several
in-stances in Rochester the house painter was shown how to do this.
(
5) The simplicity of performance and easeof imiterpretation has proven this spot test an
adjunct to screening campaigns to identify
early cases of lead poisoning.
JAMES W. SAYRE, M.D. Department of Pediatrics
DAVID
J.
WILsoN, Ph.D.Department of Chemistry
University of Rochester
School of Dentistry
EXPERIENCE AND REASON-BRIEFLY RECORDED 785
Spectroscopic lead analyses were performed by Luville T. Steadman, Ph.D., Department of
Radia-tion Biology’ and Biophysics of the University of
Rochester, for which the authors are greatly
appre-ciative.
REFERENCES
1. Chisolm, J. J., and Harrison, H. H. : The
expo-sure of children to lead. PEDIAmIcS, 18:943, 1956.
2. Barltrop, D., and Killala, N. J. P.:Factors
influ-encing exposure of children to lead. Arch. Dis. Child., 44:476, 1969.
3. Kaplan, E., and Shauhl, R. S. : Determination of
lead in paint scrapings. Amer. J. Public Health, 51:65, 1961.
4. Thienes, C. H., and Haley, T. J.: Clinical
Toxi-cology. Philadelphia: Lea and Febiger, 1964.
5. Brown R. A. :Personal communication.
Testicular
Calcification
in a
4-Year-Old
Boy
Bilateral diffuse testicular calcification is a striking and unusual finding on an x-ray film.
This report describes a healthy 4-year-old boy
with such a picture.
Testicular calcification is uncommon in chil-dren. Even in childhood hyperparathyroidism, soft tissue calcifications outside the kidney are
rare.1 Intra-abdominal ovotestes have been
seen to be diffusely calcified.2 Tumors of the
testis, such as teratomas, may calcify, but these
calcium deposits are usually unilateral and
ir-regular. The calcifications that occur in the
scrotum following meconium peritonitis are
usually coarse and bilateral and can be seen
anywhere within the tunica vaginahis. Diffuse,
finely stippled calcification of both testes as
seemi by x-ray has not been described
previ-ously in a well boy.
CASE REPORT
This 4-year-old boy was brought to the
Erner-gency Room of Roosevelt Hospital because of a
pharyngitis and tenderness of the right thigh. An
x-ray of the pelvis and right leg revealed normal
bone configuration and no evidence of tumor or
os-teomyelitis. Both testes, however, were noted to be
diffusely calcified (Fig. 1). There was no history
of any urinary tract abnormality or familial disease.
His past history revealed a normal delivery and
neonatal period. At 2 months of age he had bilat-enal scrotal swellings felt to be hydroceles, which
had resolved spontaneously. His development and
health had been good except for several episodes
of pharyngitis and otitis media, and one hospital admission for a Salmonella entenitis 1 year
previ-ously. On examination, the abdomen was
unre-mankable. Both testes were fully descended,
nor-mal in size and firm, but not remarkably hand to
the touch. The penis was uncincumsized.
A month following the demonstration of
testicu-lar calcification by x-ray, the boy was noted by his
parents to have a right inguinal swelling which
was due to a right inguinal hernia. At the time of
admission for hernia repair in December, 1967, the following laboratory results were obtained:
uninaly-sis normal; hemoglobin 11.8 gin; hematocnit 31%;
WBC 12,600 with 58% poiss, 5% eosinophils, 1%
monocytes and 36% lymphocytes. Repeated serum
chemistries showed: Ca 10.5, 10.0, 9.6, 10.5 and 9.7 mg/100 ml; P 3.6, 4.3, 4.2 mg/lOO ml,
alka-line phosphatase 21, 16, 19 KAU; total protein 7.4, 7.6 gm/100 ml with albumin 3.7, 4.0 gm/100 ml,
BUN 20, 14 mg/100 ml. Bilinubin, sugar, and
ESR were all normal. Twenty-four hour urine
col-lection showed 64 mg of CA (normal 50 to 400
mg) and 416 mg of P (normal 340 to 1,000 mg). The buccal smear was normal for a male. A pelvic
x-ray again showed diffuse homogeneous
calcifica-tion of both testicles. Chest, abdominal, and
verte-bral x-rays were normal and did not show any
other abnormal calcifications. The EKG was
nor-mal.
During this hospital admission the bcy
devel-oped a beta-hemolytic streptococcal pharyngitis.
He was treated with penicillin, and then
re-admit-ted in February, 1968, for a night inguinal
hernior-rhaphy, right testicular biopsy, and circumcision. At the time of testicular biopsy, the testicular tis-sue had a firm, slightly gritty consistency when cut
with a knife. He did well and was discharged on
the second postoperative day. Two years
postoper-atively, both testes had increased slightly in size
and were unremarkable on examination.
Chromo-some analysis of peripheral blood lymphocytes
re-vealed a normal male karyotype (46 XY).
PATHOLOGY
The testicular biopsy (Fig. 2) showed small
normal appearing seminiferous tubules lined
by Sertoli cells. In the fibrous tissue between
the tubules there were a few large cells which
had abundant eosinophihic cytoplasm with
granules of l)rOWniSh pigment but no Reinecke
crystals. They may represent interstitial cells.
Most of the tubules contained no lumemi. In
some, larger cells with round nuclei and
well-delimited cytoplasm were seen centrally in the
tubules. Approximately one-third of the tubules had a dilated lumen which was filled with a large eosinophihic spherical laminated structure
