University of California Berkeley’s Health Research for Action is calling on OSHA to revise its occupational health standard on lead, which is now 30 years old. In a report entitled “Indecent Exposure: Lead Puts Workers and Families at Risk,” the authors describe the adverse health effects of lead in workers with blood-lead levels of 5-10 ug/dL—a fraction of OSHA’s medical removal trigger of 60 ug/dL. They note:
“…extensive research has shown that lead causes significant health problems in adults at much lower levels. Cumulative exposure to low to moderate levels of lead has been associated with an increased risk of hypertension and reduced cognitive and kidney function. …[and] exposure during pregnancy has been associated with an increased risk of miscarriage and impaired fetal growth…”
The Health Research for Action’s authors draw on work published over the last decade, in particular, articles published in NIEHS’s journal Environmental Health Perspectives, including:
- Navas-Acien, et al.’s Lead exposure and cardiovascular disease (2007) in which the authors concluded: “current occupational safety standards for blood lead must be lowered.”
- Kosnett, et al.’s Recommendations for medical management of adult lead exposure (2007) in which the authors suggest more intensive and frequent medical monitoring of lead-exposed workers.
- Schwartz and Hu’s Adult lead exposure: time for change (2007) who suggest that “lead poisoning must be thought about as a chronic disease. Once a significant lead body burden has accumulated, the health effects are likely to be progressive and, to a large degree, irreversible.”
- Spivey’s article Weight of lead: effects add up in adults (2007)
- Â Schober, et al’s Blood-lead levels & deaths for all causes: Results from NHANES IIIÂ (2006)
As well as the Association of Occupational and Environmental Clinics (AOEC)’s medical management guidelines for lead-exposed adults (revised April 2007).
Health Research for Action provides just a sample of the compelling evidence that workers’ health continues to be harmed by workplace exposure to lead. They note that among the 37 states with blood-lead reporting systems:
“1,649 adults in 2003 and 1,425 in 2004 had blood lead levels of 40 ug/dL or higher”
and in California alone,
“2,390 adults in 2004 had blood-lead levels between 10 to 39 ug/dL.”
 As I noted last year in Lead-Poisoned Workers in Alaska: Miners Beware!, some of the lead poisoning cases can be linked to a particular workplace, but we don’t necessarily have adequate regulations to PREVENT the exposure.  (MSHA, for example, doesn’t have a standard to protect mine workers from lead poisoning.) When we see data showing that workers already are lead poisoned, this is the ultimate sign of failure. Our nation’s lead-poisoning prevention measures are inadequate.
Health Research for Action’s report “Indecent Exposure: Lead Puts Workers and Families at Risk,” offers the following “Prescription for Change”:
- Eliminate all unnecessary uses of lead
- Revise OSHA standards
- Reward compliance
- Expand employer education and consultation
- Expand worker education and outreach
- Set enforceable reporting standards for clinical laboratories that perform blood lead tests
Until someone corrects me, I’m saying the OSHA lead standard promulgated in 1978 is still the strictest in the world. Compare the PEL of 50 ug/m^3 and the action level of 30 to anything around the world.
At the time, public health professionals and the labor movement opposed a biological standard. Nevertheless, the medical removal protection – multiple physician review provisions also drove exposure controls. Not so much the 50 ug/100g three test moving average for removal, but the requirement that the employer maintain wages until the lead in blood gets below 40. So employers typically transfer – and pay MRP – between 40 and 50. Fit testing requirements for respirators also made a difference.
It’s not clear what measurable lead-in-air level corresponds to 40 ug/100g – models predict substantially higher LIB at 50 ug/m^3 than is actually observed.
Over the past 30 years, many workers with high past body burdens have left the workforce, so you might be able to reduce the LIB removal and still have quantifiable airborne exposures to abate. But 10 ug/100g is below that level, it would be a pure biological standard.