by: Capella Tucker, August 14, 2006 5:08:00 am
Maria Vasquez has brought her four year old son, Luis, in for a follow-up screening for lead toxicity. Ben Taub Pediatric Lead Clinic Director Doctor Marcus Hanfling goes through a list of questions having to do with the child's environment. Other questions eliminate other problems...
"Que medicine sus medicino ... perfecto."
Luis is taking his vitamins with iron.
"If you're iron deficient then you absorb more of the lead, that's one problem. And two, if your iron deficient some of the same signs, same neuro-cognitive problems that you have with lead toxicity can be actually seen with iron deficiency so the two exacerbate the same problem."
Hanfling says neuro-cognitive problems that develop with iron deficiency seem to be reversible ... damage from lead toxicity is not.
"If you have a one time exposure, it would take about three months for that level to come down, which is still a fairly long time when you think about it. And then the longer the exposure, then you start getting deposition or the lead starts settling out in your soft tissue and the parts of the bone that move back and forth, so that can take up to three years. And then it can be in sort of your non-mobilizable bone, or relatively non-mobilizable bone, and your half-life can be upwards of 30 years."
Hanfling says public policy efforts have been successful lowering the number of children affected by lead.
"We pretty much are equal to the national average in terms of the percentage of children who presently have levels greater than ten. We run about three to four percent of our kids in Houston have levels greater than ten."
In 1991, the Centers for Disease Control dropped the level of concern for lead to ten micrograms per deciliter. There are several tricky things about treating lead toxicity ... first, symptoms are not obvious and second, there's no traditional medical treatment. The only way to combat lead toxicity is to remove the source of the lead.
"We have a goal and this is nationwide that by 2010 that we eliminate this problem as a national public health risk."
Richard Williams is program manager of the Lead Hazard Program in Harris County. The staff handles education outreach and case managment. Williams says they also go to people's homes, who qualify, to investigate possible sources of lead. He says on average they do about 80 site visits a year with 50 of the homes testing positive for lead.
"County-wide we have about 142,000 homes that potentially have lead-based paint hazards. So that's probably about 50 percent of homes that we have."
The primary source for lead poisoning is still believed from lead-based paint in older homes, especially around doors and windows. Nurse Case Manager Judy Zoch...
"Most of the older people are familiar with the problem, but a lot of them think it's been eliminated because it's been removed from gasoline and no longer at high enough levels to cause concern in interior paint. But what they are not aware of is that the older homes still have lead paint in them."
Other common sources are clay pots and home remedies for some ailments in children. Capella Tucker, Houston Public Radio News.