Getting the Lead Out of Your Young Patients

Although childhood lead poisoning is preventable, it remains one of the most common health problems in the U.S. among children

By Tammy L. Eisentrout, DO

?Nationwide, lead prevention, testing, follow-up and treatment have been grossly neglected. Despite the fact that childhood lead poisoning is entirely preventable, it remains one of the most common health problems in the United States among children.(20)

According to data from Phase 2 of the National Health and Nutrition Survey (NHANES) III, approximately 890,000 children between the ages of one to five years of age had blood lead levels greater than or equal to10 ug/dL.(19) The Ohio Department of Health designates blood lead level reference ranges as greater than 0 to less than 10 ug/dL background exposure, 10 to 14 ug/dL low toxicity, 15 to 19 ug/dL mild toxicity, 20 to 44 ug/dL moderate toxicity, 45 to 69 ug/dL high toxicity and greater than 70 ug/dL as severe toxicity.(23)

While all children are susceptible to lead exposure, socioeconomic status plays a major role in a child’s risk for having significant amounts of lead in their environment. There is a tremendous discrepancy of elevated blood lead levels (BLLs) between those children living above and those living below poverty level.

“Medicaid enrollees accounted for 60 percent of children ages one to five years who had BLLs greater than or equal to10 ug/dL, and 83 percent of young children with levels greater than or equal to 20 ug/dL.”(4) “Children ages one to five years were more likely to have elevated BLLs if they were poor, of non-hispanic, black race or lived in older housing.”(25) Therefore, socioeconomic factors associated with increased blood lead levels include age (youth), gender (male sex), ethnicity (non-hispanic, black), residence in older housing and poverty.(1, 22)

Prior to 1990, leaded gasoline provided the major source of lead in the environment.(12) The addition of tetraethyl lead to gasoline was first performed by Thomas Midgely, a chemist at General Motors. It was discovered to be a proficient “antiknock agent,” and boosted a motor’s power. Thus, leaded gasoline persisted on the U.S. market for almost 70 years. With the banning of lead in gasoline in 1990, BLLs in both adults and children were significantly reduced.(2) Despite the eradication in gasoline, lead remains a common environmental pollutant. Other sources of exposure include lead-based paint, soil, dust, tap water, parental occupations and hobbies, air and food.

The Consumer Product Safety Commission banned the use of lead-based paint in residential housing in 1978.(20) Yet, it has been estimated by the Department of Housing and Urban Development that approximately 3.8 million houses with children contain chipping lead-based paint or high levels of dust containing lead.(3) “About 74 percent of privately owned, occupied housing units in the U.S. built before 1980 contain lead-based paint.”(20)

Lead Consumption
Children consume lead by eating paint chips, and by ingesting or inhaling dust and soil. Frequently, lead toxicity occurs when houses containing lead-based paints are improperly renovated or remodeled. As a result, children are exposed.

Lead-laden soil and dust also are major contributors to lead exposure. They serve as vehicles where substances containing lead, such as paint and gasoline, are more likely to be ingested and evade cleanup.(20)

Children frequently put their hands and other objects into their mouths, and wash their hands infrequently. Small children are likely to be in the very spots where lead-contaminated dust collects on floors, as well as dirt from outside. “Although lead emissions from gasoline have largely been eliminated, an estimated four to five million metric tons of lead used in gasoline remain in dust and soil, and children continue to be exposed to it.”(13)

Drinking water contamination also continues to be a significant cause of toxicity. Children may absorb greater than 60 percent of the lead present in water.(14) The use of lead in pipes to construct drinking water systems was stopped by the Safe Drinking Water Act Amendments of 1986. However, many private residences, as well as older, un-renovated public facilities still contain lead in the distribution system. Lead may be present in the pipe itself, soldered joints or connections, fixtures, or fountains and coolers.(20)

Water, allowed to stand for long periods of time or hot water may have the greatest concentrations of lead. “Several babies have been poisoned when hot tap water, which was then boiled (resulting in a higher concentration of lead), was used to make baby formula.”(8)

Even family members may serve as vehicles for the transportation of lead to children. Those working as smelters, battery plants, home repair or bridge demolition may harbor the substance on their clothing. Likewise, those with hobbies such as making pottery, stained glass, reloading ammunition or furniture refinishing may unknowingly create or carry the lead dust into the home.(20)

How much is too much?
What amount of lead exposure becomes detrimental, and at what blood lead level is the toxicity significant? It is unquestionable that lead toxicity at serum lead levels greater than 50 ug/dl can cause multi-system effects. This includes hematologic effects such as basophilic stippling, decreased hemoglobin synthesis and may even progress to frank anemia.

Children may experience gastrointestinal effects such as nausea or colic. Renal effects include nephropathy. Since children’s nervous systems are developing so rapidly, they may experience decreased Intelligence Quotient (IQ), hearing and nerve conduction.

Chronic lead exposure also causes reduced activation of vitamin D and decreased stature.(20) However, by far the worst complication is lead encephalopathy. The encephalopathy occurs over weeks to hours. It is marked by a progression from headache, vomiting and seizures to coma and even death.(10, 24)

Unfortunately, there are no reliable studies that give exact numbers regarding what level of lead is needed to impart effects on a child. A study by Needleman et al., on dentine lead levels on teeth shed by first and second graders, showed those with levels greater than 20 parts per million (ppm) had seven times the risk of not graduating high school, and six times the risk of developing reading deficiencies. Children also showed decreased vocabularies, attention and fine motor disabilities, increased absence from school, decreased hand-eye coordination, lengthened reaction times and a lower class rank.(17)

“Epidemiological studies have identified harmful effects of lead in children at blood lead levels at least as low as 10 ug/dL. Some studies have suggested harmful effects at even lower levels, but the body of information accumulated so far is not adequate for effects below about 10 ug/dL to be evaluated definitively.”(20)

What is well established is that lead is a neurotoxin. It affects the activity of neurotransmitters and adenyl cyclase in the brain, as well as dendritic complexity.(16) Fergusson et al., points out that it is only reasonable that even small amounts of lead would have at least some residual impact and perhaps even a continuum of dose related effects.(7) The study showed, “There were small but relatively consistent and stable correlations between dentine lead values and behavior ratings.”(7) However, children often exhibit no obvious signs or symptoms of increased serum lead levels. Exposure is often insidious and chronic, so it is very easy for increased serum lead levels to go unchecked.

The Center for Disease Control (CDC) recommends all children six months to six years old be screened for lead. Children are essentially placed in one of three categories: Medicaid, high-risk zip codes and low-risk zip codes.(23)

All children enrolled in Medicaid must follow the revised 1998 Federal Medicaid guidelines for testing. They now require that children have a blood lead testing done both at 12 months and 24 months of age. Additionally, children ages 36 to 72 months old must have at least one blood lead test done if they have never had one done in the past. A risk assessment questionnaire in lieu of a blood lead test is not acceptable and at present, there is no waiver to this Medicaid requirement.(22)

The remaining two categories are composed of patients not enrolled in Medicaid. Based on what zip code a child lives in, each child is assigned to the high-risk zip code group or low-risk zip code group. For a zip code area to be considered a high-risk area at least 27 percent of the houses must have been built before 1950, and at least 15 percent of the children over five are living below poverty level.

Alternatively, a zip code area can become high-risk if at least 12 percent of the children under 36 months of age were found to have a BLL greater than 9 ug/dl during the previous calendar year.(2) Those children living in a high-risk zip code are recommended to have blood lead levels drawn at least twice between the ages of six months and 36 months with at least 12 months in between blood lead level drawings. Children 36 to 72 months must have a blood lead test if one has never been done.(23)

The remaining children not enrolled in Medicaid and not living in a high-risk zip code area fall into the low-risk zip code category. Any child living in this area under the age of 36 months should be screened with the Risk Assessment Questionnaire (RAQ) (Figure 1) at least twice with at least 12 months in between each occasion. Children ages 36 to 72 months must be screened with the RAQ at least once if it has never been done. If any questions are answered are “yes” to the RAQ, a blood lead level must be done.

Though screening recommendations are in place, a significant number of children still do not have their blood lead levels checked. In a study performed between 1991 to 1994, “an estimated 81 percent of children enrolled in Medicaid had not been screened with a blood lead test.”(22)

“Of an estimated 535,000 children ages 1 to 5 years who were enrolled in Medicaid and had elevated BLL, 352,000 (65 percent) had not been screened with a blood lead test and, therefore, did not receive appropriate medical and public health case management follow-up care and environmental services to reduce their BLLs.”(22)

Clearly, there are many loopholes that children may slip though without receiving a lead screening. Problems with getting children screened for lead lie primarily with physicians and parents.

Physician neglect
There are a number of ways by which physicians neglect to protect their pediatric patients from lead. First, a physician must have an appreciation of the effects of lead, and knowledge of whom and when to test for lead. They also must know how to appropriately evaluate and treat an elevated level should one occur.

Secondly, a physician must be in the habit of regularly ordering serum lead levels and administering RAQs as part of regular health maintenance visits. Reminders may need to be incorporated into vaccination updates or as part of worksheets that track milestones.

It also may be necessary to do lead screening as part of sick visits for those patients who are poorly compliant with well-child care.

The third, and probably most important role of a physician, involves parent education. It is up to the physician to impress upon parents the importance of well-child visits, having lead levels checked and followed-up. Physicians must be the “cheerleaders” in encouraging parents to do their part.

A lab requisition simply stuffed into a purse or pocket will likely not result in a child being taken for a blood draw. The Office of Ohio Health Plans (OHP) is currently working on a “birthday card,” for one and two year olds enrolled in Medicaid that will remind parents to have lead testing, as well as other well-child screenings performed.(9)

Physicians also must teach parents about lead cleanup and provide handouts on how to reduce lead around the home. This is especially pertinent if parents are residing in a home built before 1978, or renovating an older home.(2) Appropriate information and tips can help parents keep their children safe.

Parents also have multiple reasons and excuses for not having lead testing/screening performed. Since some children rarely get medical evaluations and even fewer get regular ones, they have little or no chance of ever receiving one, let alone two, recommended lead screenings.

Parents also may not be able to afford the office visit, as well as not want to make the time needed to bring their child to a medical visit. This is especially true if the parents view the visit as unnecessary, specifically when their child appears healthy.

Taking a child to a busy lab is yet another matter. Parents forget or lose lab requisitions, or they forget about taking their child to the lab altogether. They must also find time in what may be an overbooked and overworked schedule. Also, this blood draw will usually be an addition to a whole battery of vaccinations that parents must watch their loved one endure.

In concert, all the necessary elements must be in place for proper lead testing to occur. With so many steps susceptible to failure or neglect, it’s no wonder why lead screening rates are so low. According to Job and Family Services in Ohio, 31 percent of one year-olds enrolled in Medicaid in 1999 had BLLs tested, and only 36 percent had BLLs checked in 2000. The figures for two year-olds are even more disheartening. In 1999, 22 percent were tested and in 2000, only 24 percent were tested.(21)

Yet, if parents receive appropriate education from physicians, as well as state and local agencies, they may prevent or significantly reduce lead exposure from happening in the first place.

Lead abatement
According to Title X of the Residential Lead-Based Paint Act of 1992, persons leasing or selling a house must disclose any lead-based paint hazards and provide a pamphlet (produced by the Environmental Protection Agency) on lead hazards.(11) They also must permit an inspection or risk assessment of the home for any lead-based hazards. In homes where lead is present, lead abatement, which removes the lead or installs barriers to make it inaccessible to children, is the safest way to reduce lead in a child’s environment.(20) However, abatement is quite costly and not always possible in every situation. “Generally, owners are responsible for providing properties that are lead-safe and surfaces that are cleanable. Residents are responsible for performing ordinary household cleaning of those surfaces, particularly floors and exterior and interior window sills.”(11)

Children are at greatest risk in homes being renovated. “De-leading or lead paint abatement can be an effective method of reducing children’s exposure to lead in paint and house dust if properly done,(5) but may actually increase dust lead levels if not done properly.”(6) “One study found that refinishing activity performed in dwellings with lead based paint was associated with an average 69 percent increase in the blood lead level of the 249 infants living there.”(11)

Household wood coated with lead-based paint, when burned, generates leaded fumes. The resulting ashes also contaminate outside surrounding soil if not disposed of correctly.

Whenever lead-based paint is heated above 1100° F, some of it may vaporize and later settle on the surrounding walls and floors. These small particles (fumes) are extremely dangerous because they can be inhaled by the lungs and rapidly absorbed into the body.” (p. 4.4) Only professionals, trained in safe and proper lead abatement, should be allowed to renovate homes containing sources of lead (p. 18). Those untrained in lead removal should not attempt repairs involving lead hazards. “In adults, lead poisoning can cause irritability, poor muscle coordination, nerve damage to sense organs and nerves controlling the body, and may cause problems with reproduction (such as decreased sperm counts). Lead poisoning may also increase the blood pressure in adults. Retarded fetal development can occur at even low blood levels.” (4)

During the renovation period, all personal affects, draperies, and furniture should be stored away from affected areas. However, older curtains, carpet, furniture, or belongings may harbor lead dust. In this case, all affected items should be properly disposed. The area being renovated must be sealed off from the rest of the house. Pregnant women, people with hypertension, and children must find temporary residence elsewhere and may not return to the household until abatement is complete. Food, food containers, and eating utensils must be removed from the area. Eating and drinking must be prohibited in the area. Clothing worn by workers or those entering the contaminated area must be appropriately disposed (p. 45). “Exterior containment involves covering the soil or pavement around the building to a distance of 10 to 20 feet (possibly less in some situations.” (p. 4.7)

In the event that complete abatement is not feasible, temporary measures must be taken by owners and or residents to reduce as much lead exposure as possible. Temporary measures offer improved safety but not complete protection from the hazards of lead. The efficacy of these measures is largely dependent on the extent of lead contamination and condition of the house. It is also dependent upon the craftsmanship and persistence of those halting off the exposure. “Moisture from leaky pipes or roofs can quickly cause paint that was smooth and intact to blister and scale, generating hazardous levels of lead dust.” (p. 45)

Children must be blockaded from areas of chipping, peeling, or flaking paint. “Heavily-leaded paint was used in about two-thirds of homes built before 1940, one-half of homes built from 1940 to 1960, and some homes built after 1960.”(4) Though paint containing greater than 0.06 percent lead by weight was banned for residential use in 1978, higher lead based paint can be found in newer homes. Lead paint from industrial, military, and marine sources sometimes find their way into homes (p. 14). “It is unusual but not impossible to find lead-based paint in houses built after 1978. For example, some health departments still confiscate new residential paint containing illegal amounts of lead.” (p. 3.8)

Deterioration of paint is most likely to occur around windows, windowsills, and doorframes. The resulting particles of paint are accessible to children for chewing and ingesting (p. 23).

ncapsulation of lead-based paint involves applying a liquid or adhesive coating; it provides a temporary barrier from the hazard (p. 13.5). However, only trained professionals should perform these repairs. Repainting or any disturbance of the paint may, like any other renovation activity, cause greater contamination. Additionally, encapsulation is suitable only for areas that are not significantly deteriorated; for example, the painted area must not have areas that are mostly cracked, chipped, or peeling (p. 13.7). Otherwise, the paint must be completely abated.

Wood floors or other hard surfaced flooring must be regularly wet mopped but never dry mopped. Dry mopping or regular vacuuming can potentially aerosolize or spread lead dust over an even greater area. Vacuuming of debris remaining from a renovation should be done using only a vacuum with high efficiency particle absorption (HEPA) filter. Surface areas should be cleaned with a detergent containing at least five percent trisodium phosphate (TSP) (p. 14.9). “TSP detergents are thought to work by coating the surface of dusts with phosphate or polyphosphate groups which reduces electrostatic interactions with other surfaces and thereby permits easier removal.” (p. 14.9) High phosphate detergents can sometimes be difficult to find since TSP is considered an environmental pollutant and causes skin and eye irritation. Detergents containing high TSP can sometimes still be found in hardware stores and may be used in situations such as lead clean up. Trials on alternative cleaning agents that may be more effective and safer are being performed (p. 14.9-22).

Contaminated drinking water may still be a concern in some homes. Pending the removal of all lead piping and connections, only cold water from fully flushed conduits should be used for consumption. Temporary measures to control outside contaminated soil include, planting grass or ground cover (p. 23).

Nutrition is a key issue to discuss with parents. Toxicity, distribution, and absorption of lead are greatly impacted by a child’s diet as well as other factors. Higher amounts of lead are absorbed on an empty stomach, so it important that children at risk eat regular meals (p. 11 and 23). “From experimental studies, gastrointestinal absorption of lead from nonfood sources is decreased in the presence of food.” (p. 11) Children who are iron deficient also have higher rates of lead absorption. Unfortunately, iron deficiency coincides with lead toxicity in many children (p. 34). Additionally, “Deficiencies in iron, calcium, protein, and zinc are related to increased blood lead levels and perhaps increased vulnerability to the adverse effects of lead.” (p. 11)

This paper examines the Erie County Family Practice Clinic to see how lead testing can be overlooked and how it can be improved. According to records, the resident/intern run clinic saw approximately 4,438 patients in the year 2001. Approximately 64 percent of those were Medicaid patients, with a fraction being pediatrics. On March 13, 2002, the Ohio Department of Health (ODH) sent notices to Medicaid providers evaluating their performance of lead testing in the year 2000. ODH data was obtained through Medicaid and STELLAR Central Registry data(21). According to the report, the Erie County Family Practice Clinic saw 64 twelve-month-old children for well-child visits. Only seven of those children had a BLL test, a total of 11 percent. Of the 34 children that were seen for well-child visits at 24 months of age, only eight had BLL checked, 24 percent. Of all twelve and twenty-four month olds seen in the year 2000, a total of 85 percent had not had BLL drawn (21).

In an effort to discover why so many children are not getting evaluated for lead, the single intern and eight residents at the clinic were given anonymous questionnaires regarding lead testing at the clinic. It was designed to evaluate their baseline knowledge of lead as well as survey their opinions and experience with barriers to getting BLL’s. (Figure 2) is the lead questionnaire given to the residents and intern.

Questionnaire results
In reviewing all nine returned questionnaires, it was obvious that knowledge regarding lead was quite varied. On the question regarding which Medicaid children should be lead tested. None of the participants were able to correctly answer the question.

All but one physician was aware that the Sandusky zip code, 44870, is considered a high-risk zip code. This is important when seeing non-Medicaid pediatric patients at the clinic. Almost all children seen at the clinic are either Medicaid patients or those living in a high-risk zip code area. Therefore, only BLLs and not RAQ’s would be appropriate screening measures for nearly all the pediatric patients seen at the clinic.

As mentioned previously, there is at present no waiver for the BLL requirement for Medicaid patients. Five of the nine physicians answered this question correctly. All nine physicians did correctly identify lead contaminated dust as the most common source of lead contamination. Four physicians correctly answered 10 ug/dl as the lowest blood lead level that the Advisory Committee on Childhood Lead Prevention lists to be associated with adverse effects. When asked what percent of Medicaid enrolled 12-month-old children received BLLs at the Family Practice Clinic one person did correctly answer 11 percent. Two physicians correctly identified a high phosphate level as being most important characteristic of soap when cleaning lead dust.

All but two residents admitted that they sometimes forget about screening. Four physicians indicated that some of their patients were tested at Women, Infants, and Children (W.I.C.). This was actually a trick question. Many parents tell training physicians that W.I.C. tested their children for lead. However, W.I.C. does not perform lead testing, only capillary hematocrits. All residents agreed that parents forget to take their children to the lab. Five physicians indicated that, patients losing their lab requisitions were significant barriers.

Finally, residents were asked what they felt were the biggest obstacles to getting screenings completed and what resolutions would help improve the number of patient screened. Most listed parents and compliance as a significant obstacle. One person suggested that nurses who did not want to perform venipuncture forced parents to take their children to the hospital lab, thereby significantly reducing compliance. Two other residents suggested that on-site drawing of BLLs would significantly improve the rate of screenings done at the clinic.

The results of the questionnaire identifies that there are many areas that could potentially improve the number of screenings that are performed at the clinic. Based on the number of incorrect answers given by the physicians regarding lead knowledge, it is clear that there is significant room for improvement. Possibly an in-service, lecture or distributed articles could improve the knowledge base among residents. There was a lead information handout given to physicians at the clinic from the health department nurse in charge of lead prevention. This material contained information on who should be screened, how to treat a toxic lead level and an article on how the government has been involved in lead prevention. However, what it lacked was information on teaching parents how to deal with possible lead sources in the home. It also did not give advice on making improvements within the practice to improve compliance.

With the complexity of which age groups should be tested, perhaps a reminder poster, giving specifications of just who needs testing and when, could resolve some confusion. This year, a reminder for lead testing was added to the modified Denver form that is filled out for each child during well-child visits.

Perhaps, if blood lead levels were drawn when children come in for their vaccinations, compliance would improve. However, without on-site testing and the automatic drawing of BLLs in conjunction with vaccination schedules, it is unlikely that significant improvements in the number of children screened for lead will ever occur.

Conclusion
Lead remains a significant problem in many U.S. communities. Without proper screening, children face many consequences, including death. Children, being unable to protect themselves from their environment or from the lack of compliance of their parents, have little to no defense.

The burden of protecting children from lead contamination rests largely on physicians, but pressure on state and federal public health policy must be maintained, if not strengthened. Only they can institute office practices that create a largely foolproof regimen for screening children for lead. While problems may lie with parental compliance, solutions lie with proactive physicians.

Tammy Eisentrout, DO, graduated from Philadelphia College of Osteopathic Medicine in 2000. She completed her Family Practice Residency in Sandusky Ohio at Firelands Regional Medical Center in 2003. Dr. Eisentrout is board certified in Family Practice. She is currently the Chairman of the Department of Family Practice at Doctors Hospital in Massillon, Ohio.