# Presentation: 442451

## Lead

**Medical Grand Rounds Seminar**

## Learning Objectives

**Explain what lead is**
**Identify where lead is most commonly found in the United States today**
**Identify the most important routes of exposure to lead**
**Identify the populations most heavily exposed to lead**
**State the CDC’s level of concern for lead in children’s blood and recommendations for screening **
**State the OSHA level for intervention for occupational exposure to lead**

## Learning Objectives (cont’d)

**Describe the way lead is taken up, distributed, and stored throughout the body **
**Describe at least three major physiologic effects of lead**
**Name three symptoms of mild lead toxicity**
**Name three symptoms of acute lead toxicity**
**Name the most useful test for lead toxicity**

## Learning Objectives (cont’d)

**List three steps that should be take at blood lead levels between 10 and 19 mcg/dL**
**Describe additional steps that should be take for BLL 20-44 mcg/dL, 45-69 mcg/dL and 70 mcg/dL and above  **
**List steps patients with domestic exposures can take to reduce lead exposure**
**List steps patients with occupational exposures should take **

## Soft blue-gray metal 
Found in thenatural environment
Was added to paintand gasoline in past 
Still used in consumer products

**Found in the****natural environment**
**Was added to paint****and gasoline in past **
**Still used in consumer products**

**What is Lead?**

***the natural ore galena***

## How Does Lead Get Into the Environment?

**Deterioration of lead-based paint**
**Leaded gasoline**
**Businesses that involve lead**
**Lead mines or smelters **

## How Are People Exposed to Lead?

**Dust, paint, and/or soil**
**Contaminated food, water, or alcohol**
**Some imported home remedies and cosmetics**
**Endogenous exposure**

**Notes:**
Separate bullet on soil near mining/smelting?  Water?

## Lead in Home Environments

** ****Pre-1978 homes with deteriorated leaded paint **
** ****Children at greatest risk **
** ****Most exposure through leaded dust in home**
** ****Lead dust levels have been directly correlated ****	****with children’s BLL**

## How Are People Exposed to Lead in Work Environments?

**Swallowing lead dust**
**Breathing contaminated air**
**Lead contacting skin**
**Workers can expose****their families if they****bring lead home on****their clothes or skin**

## What Jobs Involve Lead? 

**Lead smelting****or mining **
**Construction/ remodeling**
**Automobile repair**
**Plumbing**
**Police officers/military**
**Many others**

## What Hobbies Involve Lead?

**Car repair**
**Artistic painting**
**Stained glass**
**Pottery glazing**
**Soldering**
**Target shooting**
**Making bullets, slugs or fishing sinkers**

## Lead can enter water by leaching from	
Lead-containing pipes
Brass faucets
Solder
Boiling does not get rid of lead
Running cold water beforeuse may reduce exposure	

**Lead-containing pipes**
**Brass faucets**
**Solder**
**Boiling does not get rid of lead**
**Running cold water before****use may reduce exposure****	**

**Lead in Drinking Water**

## Lead in Commercial Products

**Lead is still used in products such as:**
**Bridge paint**
**Computers**
**Solder**
**Pewter**
**Ceramic glazes**
**Jewelry**
**Automotive batteries**
**Imported or older                                  pre-regulation products**** ****	**

## Lead in Food Products

**Food or beverages may be contaminated through ****	**
**Production**
**Packaging**
**Storage**

## Lead in Ethnic Products

**Mexican: **azarcon,greta, liga, Maria Luisa, alarcon, coral, rueda
**Asian: **chuifong, tokuwan, ghasard, bali goli, kandu,surma, ba-baw-san
**Middle Eastern: **alkohl, saoott, cebagin
**For more examples, see Appendix 1 of:**** **http://www.cdc.gov/nceh/lead/CaseManagement

**Notes:**
Separate bullet on soil near mining/smelting?  Water?

## Lead in the Environment

**Varies from place to place**
**Soil near roadways **
**	****(pre-1976 gasoline)**
**Elevated in soil, water, or air near lead mining or smelting facilities**
**Near smaller businesses and industries that involve lead**

## Who is Most at Risk of Lead Exposure?

**Children living in****older housing**** **
**Pregnant women and developing fetus**

## Biologic Fate

**Most lead is excreted**
**Children and pregnant****women absorb more****lead than others**
**Exchanged between****blood, soft tissues,****and mineralizing****tissues**

## Physiologic Effects of lead

**No known threshold for effects of lead **
**Affects all organ systems **
**Developmental neurologic effects of greatest concern **

## Neurologic Effects of Lead

**Neurologic Effects of Lead**

**Neurologic effects on****children documented****at levels below 10 mcg/dL**
**Low exposure effects:****lowered IQ, attention deficits,****and impaired hearing**
**High exposure effects:****irritability, convulsions, coma, or death**
**Similar effects in adults at higher****exposure levels **

## Renal Effects of Lead

**Acute exposure: reversible effects**
**Chronic exposure: nephropathy (chronic interstitial nephritis) **
**Childhood exposures ****→**** adult renal disease**

## Hematologic Effects of Lead

**Interferes with production of hemoglobin**
**Can induce two kinds of anemia:**
**Acute exposure ****→ hemolytic**
**Chronic exposure ****→ synthetic**
**Threshold for adults: 50 mcg/dL**
**Threshold for children: 40 mcg/dL**

## Endocrine Effects of Lead

**Inverse correlation between BLLs and vitamin D levels**
**Chronic exposure may affect thyroid function**

## Cardiovascular Effects of Lead

**Increases risk****of hypertension**

## Developmental Effects of Lead

**Crosses the placental barrier**
**Affects fetal viability, and fetal and early childhood development**
**Maternal lead may   affect child’s neurologic development**

## Clinical Evaluation

**Preventive screening**
**Exposure History**
**Physical evaluation**
**Signs and symptoms**

## Preventive Screening

**See state or local guidance for blood lead screening**
**CDC guidelines**
**Test children at ages one and two**
**Test children annually to age six if high-risk**
**For adults, see OSHA guidelines**
**Lead exposure risk questions**

## Environmental Exposure History

**Age and condition of residences **
**Home remodeling activities**
**Occupations and hobbies of family**
**Family history**
**Maternal /exposure**
**Unusual medicines or home remedies. **
**Imported or glazed ceramics or lead crystal **
**Siblings or playmates with lead poisoning**

## Physical Examination

**Neurologic **
**Hematologic **
**Cardiovascular**
**Gastrointestinal **
**Renal**
**For children: hearing and nutritional status**

## Signs and Symptoms

**Patient may appear asymptomatic**
**Impaired abilities may include**
**Decreased learning and memory**
**Lowered IQ**
**Decreased verbal ability**
**Impaired speech and hearing functions**
**Early signs of hyperactivity or ADHD**
**Symptoms vary by exposure level **

## Signs and Symptoms: Low Toxicity

**Myalgia or paresthesia **
**Mild fatigue **
**Irritability **
**Lethargy **
**Occasional abdominal discomfort**

## Signs and Symptoms: Moderate Toxicity

**Arthralgia **
**General fatigue **
**Difficulty concentrating/Muscular exhaustibility **
**Tremor **
**Headache **
**Diffuse abdominal pain **
**Vomiting **
**Weight loss **
**Constipation**

## Signs and Symptoms: Severe Toxicity

**Paresis or paralysis **
**Encephalopathy—may abruptly lead to seizures, changes in consciousness, coma, and death **
**Lead line (blue-black) on gingival tissue **
**Colic (intermittent, severe abdominal cramps) **

## Laboratory Tests

**Venous blood sample**
**Confirm elevated finger-stick **
**Erythrocyte protoporphyrin****(EP) is no longer****considered useful**

## Complete Blood Count

**May show basophilic stippling* in patients with extended significant exposure**

*** ****Also seen in arsenic poisoning**

## Abdominal Radiograph

**Lead**

**Lead charm found in****child’s stomach**

## Longbone radiographs

- Lead Lines

- Lead Lines

- “Lead Lines” in five year old male with radiological growth retardation and blood lead level of 37.7μg/dl

- (Photo courtesy of  Dr. Celsa López Campos,
- Clinical Epidemiologic Research Unit, IMSS, Torreón, México)

## Lead Lines in Legs

- “Lead Lines” in three-year-two-month-old girl with Blood lead level of 10.6 μg/dl
- Notice the increased density on the metaphysis growth plate of the knee.

- (Photo courtesy of  Dr. Celsa López Campos,
- Clinical Epidemiologic Research Unit, IMSS, Torreón, México)

- Lead Lines

## U.S. Standards for Lead

**Blood:  **
**	****CDC level of concern for children: 10 mcg/dL**
**	****OSHA workplace standard: **
**	****	****50 mcg/dL for removal from the job **
**	****	****40 mcg/dL for mandatory notification**
**Environmental:**
**	****Agencies have set standards for lead in water, air, and soil**

## Clinical Management

**Most important step is removal of lead exposure**
**Referral to health department**
**Environmental Investigations**
**Other potential sources of lead**
**Education about prevention**

## Chelation Therapy

**At very high blood lead levels (over 40 mcg/dL for children), chelation may be indicated**
**Consult with physicians or medical centers with chelation therapy experience**

## Instructions to Patients

**Reduce source(s) of lead exposure**
**Maintain a diet high in calcium and iron**
**Continue to monitor blood lead levels**
**If workplace exposure suspected, contact:**
**Workplace health and safety officer**
**Occupational Safety and Health Administration (OSHA)**

## Instructions to Patients with Pre-1978 Homes

**Test for lead hazards**
**Assume paint has lead**
**Make sure all paint is in       good condition **
**Fix lead paint hazards ****safely**

## Use “lead-safe” work practices when disturbing paint
Work wet
Contain dust and debris
Keep children away 
Use proper equipment            and materials
Specialized clean-up and testing after work is done

**Work wet**
**Contain dust and debris**
**Keep children away **
**Use proper equipment            and materials**
**Specialized clean-up and ****testing after work is done**

**Instructions to Patients with Pre-1978 Homes**

## Avoid exposure to sources of lead
Do not let children chew painted surfaces
Wet-clean surfaces weekly
Clean window sills and wells
Do not let children play in                      bare soil
Cover bare soil in the yard with
Grass
6 inches of mulch

**Do not let children chew painted surfaces**
**Wet-clean surfaces weekly**
**Clean window sills and wells**
**Do not let children play in                      bare soil**
**Cover bare soil in the yard with**
**Grass**
**6 inches of mulch**

**Instructions to Patients with Pre-1978 Homes**

## Run cold water for 1 to 2 minutes before using
Wash children’s hands and faces 
Wash toys with soap and water
Feed children plenty of calcium 
    and iron rich foods

**Wash children’s hands and faces **
**Wash toys with soap and water**
**Feed children plenty of calcium **
**    ****and iron rich foods**
** **
** **

**Instructions to Patients with Pre-1978 Homes**

## Summary

**Primary sources: deteriorated paint, contaminated dust or soil, and some products **
**Lead is **_**very**_** dangerous to young children and the developing fetus**
**Certain workers may be exposed**
**Focus on preventing exposure/removing source**

## Summary

## How can I get more Information?

**Regional poison control center **
**Your local or state health department**
**National Lead Information Center:                                         **1-800-424-LEAD                               www.epa.gov/lead/nlic.htm
**Information on lead safe work practices: **www.epa.gov/lead/epahudrrmodel.htm
**“****Lead in Your Home: A Parent’s Reference Guide” **www.epa.gov/lead/leadrev.pdf
**Alliance for Healthy Homes:                                             **(202) 543-1147                                                           www.afhh.org

## Additional Information

**Agency for Toxic Substances and Disease Registry (ATSDR)  **www.atsdr.cdc.gov
**Association of Occupational and Environmental Clinics (AOEC)  **www.aoec.org
** **
**Pediatric Environmental Health Specialty Units (PEHSUs)  **www.aoec.org/PEHSU.htm
**American College of Occupational and Environmental Medicine  **** **www.acoem.org
** **
**American College of Medical Toxicologists **www.acmt.net
** **
**American College of Preventive Medicine **www.acpm.org