Lead Removal - Primary Source
1. Lead-based Paint in Housing
- CSPC ban in 1978 (<0.06%)
- million homes and 12 million children
-
Some household
items that contain lead-contaminated dust hazards include:
- imported vinyl
mini-blinds
- imported and antique
toys and furniture
Lead
In Mini-Blinds
Many vinyl
mini-blinds manufactured in Mexico and Asia, which are imported and sold in the United
States, contain lead. The lead in mini-blinds is used in the plastic as a stabilizer for
rigidity and for color retention. These non-glossy, vinyl blinds eventually deteriorate
from exposure to sunlight. During this deterioration, lead-contaminated dust forms on the
surface of the blinds. This leaded dust can be a hazard to children if they put the blinds
in their mouths, or if they put their hands on the blinds and the widow sills and then
into their mouths.
2. Lead Dust
- Sanding, scraping and burning
- Young children and "hand to mouth activity"
3. Lead Contaninated Soil
- Exterior paint chalking
- washouts
- deleading
- leaded gasolines
Lead
Contaminated Soil
Lead-contaminated
soil abounds in playgrounds, parks and backyards. Lead-contaminated soil poses a threat
when children play in it and put their hands or other objects covered with this soil into
their mouths. There also is a health hazard when people bring this soil into the house on
their clothing or shoes and the dust from that soil settles on the floors and other
surfaces that people touch.
The greatest source
of lead-contaminated soil is leaded gasoline. At one time the auto industry thought of
leaded gasoline as a godsend, and it was burned in nearly every automobile. When this fuel
burned, lead was released with the exhaust from the automobiles and settled on the ground.
Although the federal government eliminated most use of leaded gas in the 1970s,
approximately four to five million metric tons of lead once used in gasoline remains in
U.S. soil.
Also, leaded paint
sandblasted and scraped from buildings and bridges scatter lead chips and dust into the
soil. Lead can enter the soil by runoff from the sides of homes and buildings due to
chipping or weathering of leaded paint. Surfaces of old, outdoor clothesline poles and
playground equipment may have been painted with lead-based paint. Lead-contaminated dust
and paint chips from these surfaces can be hazardous when children play on them and then
place their hands in their mouths. Leaded dust and paint chips from this equipment also
can fall into and contaminate nearby soil.
Additionally,
although now banned, pesticides that contained lead were once used in fruit orchards and
now contaminates soil. Other industrial pollution, such as exhaust from incinerators
burning lead-containing products, contaminates soil with leaded dust.
Lead-Based
Paint On Toys and Furniture
It is important to
note that furniture and toys that are not manufactured in the United States may not
conform to lead standards. Also old or antique cribs, antique toys and furniture may have
been painted with leaded paint.
4. Lead based Paint used throughout industrial and commercial facilities
- Sanding, scraping and burning
- Ordinary wear and tear in the couse of business
5. Lead Dust in manufacturing ie Brass Smelters
- Heavy lead dust generate by the chemical processes
- disposal site on property and off
- bag house contamination and disposal of contents of baghouse
-
Some lead
related jobs and work environments include:
- battery manufacturing
- automotive parts
manufacturing
- automotive repair
- firing ranges
- carpentry
- chemical
manufacturing
- smelting &
refining of nonferrous metals
|
- plumbing
- glass productions
- demolition work
- leaded paint
abatement
- brass/copper foundry
- iron working*
|
*Bridge, tunnel & elevated highway construction valve & pipe fitting
Some lead related
hobbies include:
- making stained glass
- making pottery
- gun & rifle
activities
|
- refinishing furniture
- renovating &
remodeling homes
- making fishing lures
& sinkers
|
HEALTH EFFECTS
Introduction
Lead makes up 2% of earth’s crust. Toxic effect recognized since colonial times;
lead used in paints since 1870. Rain and ultraviolet light cause chalking off of paint
into soil around the home. Lead sources include paint pigments, certain solders,
automobile emissions, storage batteries, cable sheathing, alloys, lead mining and
smelting, plumbing and insulation activities, ammunition, etc.. Over 120 occupations are
exposed.
In July of 1786,
Benjamin Franklin wrote a letter ("The Famous
Franklin Letter On Lead Poisoning") in which he detailed his observations of the
effects of lead on the body. Franklin wrote, "You will see by it, that the Opinion of
this mischievous Effect from Lead, is at least above Sixty years old; and you will observe
with Concern how long a useful Truth may be known, and exist, before it is generally
receiv'd and practis'd on."
Mr. Franklin's
observations were correct. It was not until 1978 that the federal government banned the
use of lead-based paint in housing. Therefore, if you live in a home that was built before
1978, chances are good that it contains some lead-based paint. Dust and paint chips from
leaded paint can cause serious health hazards. Lead chips and dust can get on surfaces and
objects that people touch. Settled lead dust can reenter the air when people vacuum, sweep
or walk through it.
Lead-based paint
that is in good condition is generally not a health hazard. Leaded paint that is peeling,
chipping, chalking or cracking can pose a serious health hazard and needs prompt
attention. Removing lead paint improperly can increase the hazard to your family by
spreading even more lead dust around the house. Precautions need to be taken before
beginning remodeling or renovations on surfaces containing lead-based paint. Lead dust can
form when lead-based paint is dry scraped, dry sanded or heated.
Dust also forms when
painted surfaces bump or rub together. Lead-based paint found on surfaces that children
chew or on surfaces that get a lot of wear-and-tear also can be a serious health hazard.
These areas,
known as friction surfaces, include:
- windows and window
sills
- stairs, railings and
bannisters
- doors and door frames
- porches and fences
Usual Human Lead Exposure: Lead has no beneficial effect in animal tissues. Average
daily intake of lead by general population of 0.4 mg./person/day. Ingested lead varies
from 0.1 to 3 mg/day, while inhaled lead average .01 to .09 mg/day. If you don’t take
in over 0.6 mg of lead per day by mouth, it will not be dangerous, as lead excretion will
balance lead intake. Lead is excreted in urine and sweat.
Physiology of Lead in Body
By Inhalation:
Particles 0.5 microns reach alveoli and 30-50% is absorbed from lungs. If lead at .15
mg/meter3 in air is inhaled, those at or below .05 microns in diameter will
plateau in body fluids about 8 months later if inhaled daily with 25-30 mg of lead
retained. Ash from a cigarette contains 14 mcgm of lead; cigarette smoke itself = 0.5
mcgm. 8 mg of lead is absorbed per year from the lungs.
By Ingestion:
Average individual swallows 300 micrograms of lead per day. Only 10% of this is absorbed
into the body. Lead is in water, in ribs, coca, ground corn or corn starch, etc. A child
may absorb 50% of ingested lead. Increasing lead intake is followed by increased lead
burden in the body - a cumulative effect with increasing toxicity. Low iron, calcium, and
zinc intake increases lead absorption.
Fate in Body
Once absorbed, 90% is stored in bond as lead phosphate. The other 10% is taken up by the
red blood cells, the brain, the kidneys, and the liver, where toxic effects develop.
Average lead burden in body = 100-400 mg. Accumulation is slow, so that 1.3 mg daily will
result in 65 mcmg% in 7-1/2 years, and 3.2 mcmg% daily will give 80 mcmg% in blood in
one-half year.
Excretion
90% put out in stool; 9% in urine; It takes twice as long to excrete lead as to absorb it.
The one-half life of lead in body is 2 months. Lead excretion in the urine is usually
below 80 mcmg/liter, but if over 180 mcmg per liter, removal from work site desirable.
"Normal" Blood Lead Values
Normal values are 2 - 8 mcmg%
| Blood Lead = |
15 = abnormal enzymes with FEP
30 = anemia, fatigue, dizziness
40 = ZPP up, wrist drip, conduction time slows, muscle weakness
50 = reproductive effects, anemia, brain injury, libido reduced
80 = abdominal pain, constipation, diarrhea, anorexia, coma, and convulsions. |
Lead Levels in Industry
Lead Action Level: 30 micrograms per cubic meter of air over 8 hours
Permissible Exposure Level: 50 micrograms per cubic meter of air over 8
hours.
MEDICAL EFFECTS
In Children
All children below the age of 7 should be screened for lead poisoning by blood lead
and/or zinc protoporphyrin levels. Children develop decreased attention spans, impaired
hearing, reading and learning disabilities, delayed cognitive development, reduce ID
scores, mental retardation, seizures, coma, and death. Blood levels higher May to October.
Child can eliminate only 5 mcgm/kilogram/day. Treatment includes preventing further lead
ingestion, prevent convulsions, as 25% mortality occurs, and use of chelating agents
cautiously.
In Adults
Rarely have brain effects. Blood formation impaired, anemia, easy fatigability,
lassitude, dizziness, rapid heart beat, etc., noted. Neurological effects, include
irritability, insomnia, headache, memory impairment, tremor, apathy, fatigue, depressions,
drowsiness, stupor, delirium, convulsions, coma, peripheral nerve damage with wrist and
occasionally foot drop, muscle tremors, abdominal colic, emesis, diarrhea, impaired real
function, hypertension, gouty arthritis all occur. Reproductive effects include reduce
libido, impotence, decreased healthy sperm in men and in women menstrual abnormalities,
premature births, lower birth weights, more miscarriages, increased infant mortality, and
behavioral abnormalities (over 50 - 60 mcgm%), hence, keep below 30 mcgm%.
Organic Lead Poisoning
Exposure to tetraethyl lead fumes, as in cleaning storage tanks. Effects occur within 1
- 8 days due to inhalation of fumes, and the absorption through the skin. Effects are
acute = insomnia, lassitude, dreams, anxiety, tremor, muscular contractions, low blood
pressure, low temperature, pallor, nausea, anorexia, hallucinations, hyperactivity, and
seizures. Recovery is usually complete. High lead levels present in urine.
Laboratory Findings
Blood level elevated, ZPP and urine 24-hour lead excretion elevated. Occasionally must
do a lead provocative excretion test for diagnostic purposes using calcium EDTA.
Treatment of Lead Poisoning
Never use prophylactic chelation, as certain risks are present. Remove from further
lead exposure. May use saline cathartic, intravenous calcium gluconate to help colic,
chelation therapy with calcium EDTA or penicillamine depending on severity or poisoning.
Hospitalization and perhaps physiotherapy may be desirable. (Calcium disodium
ethylenediaminetetraacetic acid)
Costs of Lead Screening
Varies with Clinic and laboratory.
MEDICAL SURVEILLANCE
To insure the safety of all workers, LEC does the following Medical Surveillance.
Definition
In workers exposed to lead, this includes biological monitoring of worker’s blood
lead and/or zinc protoporphyrin levels with pre-employment and follow-up tests including
physical examinations to establish baseline values and appropriate medical removal and
protection benefits for the worker. This includes early detection of increased body burden
of lead, advising the employer of results as well as the worker, all at no cost to the
worker. Job protection and benefits are guaranteed to the employee.
- Periodic and Preplacement Medical Examinations
- Written Medical Opinion
- Medical Removal Protection
- Medical Removal Protection Benefits
Since there are three ways that lead can enter the body (1) through the
gastrointestinal tract via mouth; (2) through the skin; (3) through the respiratory
system, LEC provides personal protective equipment and respiratory protection.
Accordingly, thorough decontamination procedures must be established and appropriate
personal protective equipment must be used. Personal protective equipment should include
respirators and protective coveralls.
Personal protective equipment is available from many manufacturers in a variety of
forms. This availability and high level of protection has caused many employers and
regulators to demand the use of such equipment instead of looking to ways and methods of
controlling or eliminating the workplace hazard. Protective equipment has also been
selected to combat hazards because it is far cheaper than installing and maintaining
mechanical engineering controls. This cost effective approach to safety does have a
serious weakness. Again these protective devices do nothing to reduce the hazard, then
only offer protection against it. Failure to use an item or failure of the protective
equipment itself will therefore result in worker exposure to hazardous materials. If
worker safety is to be a consideration, protective equipment should only be used in
conjunction with other work site controls, particularly when dealing with airborne
hazards. Workers must be trained and taught about the limitations or protective equipment,
how to wear it, how to maintain it, and how to select the equipment most appropriate for
the job.
Personal Protection Equipment can be classified as follows:
Head Protection
- Hard Hats
- Hair Protection
- Hearing Protection
Face and Eye Protection
- Goggles
- Glasses
- Face Shields
Respiratory Protective Equipment
- Air Purifying
- Air Supplying
Hands and Feet
- Hand and Foot Protectors
- Gloves
- Foot Protection
- Boot Covers
Protective Clothing
- Coveralls (reusable)
- Coveralls (disposable)
- Underwear (disposable)
- Chemical Suits
GENERAL ABATEMENT CONSIDERATIONS
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