Lead toxicity in New York City Children
Lead serves no use in the human body and is toxic for everyone. Exposure is particular dangerous for children as it stunts the developing nervous system. Lead in childhood causing lowers IQ. It is also associated with other symptoms later on in life such as reduced height after a child stops growing and obesity.
Overall, children are much less exposed to lead now as they were a few decades ago. In New York City a 2004 housing bill provides for free testing of homes and requires landlords to make repairs. Nonetheless, the decline in exposure has been leveling off. Lead poisoning in children remains a problem.
Some common symptoms of lead poisoning in adults and children.
Lead poisoning interferes with activation of vitamin D. It also inhibits production of red blood cells, lowering hemoglobin and hematocrit. Severe cases may lead to signs of increased intracranial pressure: projectile vomiting, seizures, altered states of consciousness.
Provings for homeopathic remedies are an excellent way to see how a toxin effects the whole body. Symptoms associated with Plumbum (homeopathic lead):
- Mental: irritable, restless, apathy, anxiety or depression.
- Nervous system: spasms, trembling, rigid joints, vision disturbances, loss of feeling. Sudden neuralgic pains that radiate in all directions or shoot from the toes to the hips.
- Muscular: weakness, spasms, trembling. Muscles feel tired and ache.
- Digestive systems: pain and constipation. Constant urge for bowel movement, but only small, black, ball-shaped stools are passed. Painful urine retention. Sensation that navel being pulled into the back bone.
New York State law and blood testing for lead
Since the many symptoms are lead poisoning are nonspecific, and may not be present at all early on in exposure, testing for lead is imperative.
From ages 6 months to 6 years old, children are assessed for lead poisoning as well. Testing blood levels for lead continue if needed. After a child is found to have elevated lead, steps are recommended to remove the source of lead. Additional measures such as speech therapy may be needed.
Except for chelation in the absolute worst cases (chelation with blood levels at 45 µg/dL, there is no conventional medical treatment for lead poisoning.
Currently whole blood levels are considered elevated if above 5µg/dL. Decades ago the value was as high as 40µg/dL. For a long time the CDC had the value at 10µg/dL until research found that effects of lead poisoning could be found with levels as low as 7µg/dL.
So how did this blood test become the standard and why is 5 the borderline between a child having lead toxicity or being fine?
According to the CDC, the level was changed from 10 to 5 based on survey percentile.
This reference value is based on the 97.5th percentile of the National Health and Nutrition Examination Survey (NHANES)’s blood lead distribution in children.
The cut off levels for blood lead was never meant to be an official amount of safe exposure. No amount of safe exposure to lead has been established. Rather, these number where meant as cut off points for when lead exposure should be considered alarming.
What lab tests are available for lead poisoning?
Blood lead levels
Like with other metals and toxins, there is no test to measure total body levels. The best we can do is measure various compartments. This can be something like blood, urine, stool, or hair. The time that lead will be present in different compartments varies a lot.
Current estimates for how long lead remains in a tissues is as follows:
- Blood - 35 days
- Soft tissue - 40 days
- Trabecular bone - 3 to 4 years
- Cortical bone - 16 to 20 years
Therefore, blood tests should be considered a measurement of recent exposure only.
Erythrocyte protoporphyrin and zinc protoporphyrin measure changes that happen in red blood cells following lead exposure. Elevations in these markers are not seen until blood lead levels reach 25µg/dL. Protoporphyrin testing therefore may be used as an adjunct to blood level, but is not very useful by itself.
Elevated blood lead and normal protoporphyrin: Recent lead exposure over last 2 - 6 weeks.
Elevated blood lead and elevated protoporphyrin: Chronic exposure to lead.
Iron deficiency anemia can also raise protoporphyrin, although lead is the most likely cause.
Hair can be used for common metal toxins including lead, mercury, aluminum, arsenic, nickel and antimony. Essential elements will also be tested. Hair analysis is a valuable tool but results must be interpreted carefully. Some people will be more efficient at excreting toxins into hair.
Hair lead levels may indicate the following:
- High lead indicates lead toxicity
- Low lead - may indicate lead toxicity is not a problem
- Low lead - depending on ratios of other minerals on hair analysis may indicate that toxicity is a problem, but excretion in the hair is poor.
Nonetheless, this is a simple test that can be very helpful when interpreted correctly and used in context of the whole case. Go here for more information on hair analysis.
Below - sample hair analysis that shows lead is low. Essential elements are almost all low as well, ratios are off indicating mineral deregulation. The low levels of toxic metals are therefore more likely to indicate poor excretion than lack of toxicity.
Urinary porphyrin test
Porphyrins are produced in the production of hemoglobin. Toxins such as lead, mercury, arsenic, dioxin, PVC and PBA can interfere with the conversion of porphyrins which leads to increased excretion in urine. A urinary porphyrin test is thus a indirect test for the burden of toxicity on the body. More about porphyrin testing can be found on this page.
Functional interpretation of other labs that can lead to suspicion on lead
The following are signs on lab work that point to possible lead toxicity. If these are present it would be best to following up with other tests that are more specific.
- Anemia with low MCV and MHC
- Functionally decreased T3 (lower half of reference range)
- For adults may see low testosterone with elevated LH and FSH. In comparison with mercury may low testosterone with decreased LH and FSH.
Is screening for lead enough?
Whole blood levels are not an measurement of total body burden of lead. The 5µg/dL number for lead toxicity has been arrived at based on percentile and designed to screen out the worst cases where it known lead causes neurological damage.
Unfortunately a lot of lead from paint is still out in the environment. Additionally sources of lead include:
- Poor sources of herbal medicine
- Toys and jewelry
- Contamination from others who work around lead
Higher socioeconomic status is also not a total protection.
The 5µg/dL standard was never meant to establish safe levels of lead.
Additionally lead is just one of numerous toxic metals in the environment.
Natural treatment for toxicity
The conventional medical system is based upon waiting for a disease to appear and then treating it after the fact.
Likewise, government standards are based upon identifying single toxins that cause disease, and public health measures to remove exposure.
Toxicity studies are based upon isolating the effects of single agents. In the real world we are exposed to lead, mercury, aluminum, other heavy metals and environmental toxins as well. The synergistic effect of the hundreds of toxins we are exposed to, is not well understood, if studied at all.
Working on health care means being proactive. Toxin avoidance has to include much more than just one metal.
Considerations in helping children and adults in in a toxic world include:
- Education on toxin avoidance
- Proper nutrition
- Supplements and other strategies for detoxification
- Support for systems effected by toxicity