Barbara L. Materna

Recommendations for medical management of adult lead exposure

Research conducted in recent years has increased public health concern about the toxicity of lead at low dose and has supported a reappraisal of the levels of lead exposure that may be safely tolerated in the workplace. In this article, which appears as part of a mini-monograph on adult lead exposure, we summarize a body of published literature that establishes the potential for hypertension, effects on renal function, cognitive dysfunction, and adverse female reproductive outcome in adults with whole-blood lead concentrations < 40 μg/dL. Based on this literature, and our collective experience in evaluating lead-exposed adults, we recommend that individuals be removed from occupational lead exposure if a single blood lead concentration exceeds 30 μg/dL or if two successive blood lead concentrations measured over a 4-week interval are ≥ 20 μg/dL. Removal of individuals from lead exposure should be considered to avoid long-term risk to health if exposure control measures over an extended period do not decrease blood lead concentrations to < 10 μg/dL or if selected medical conditions exist that would increase the risk of continued exposure. Recommended medical surveillance for all lead-exposed workers should include quarterly blood lead measurements for individuals with blood lead concentrations between 10 and 19 μg/dL, and semiannual blood lead measurements when sustained blood lead concentrations are < 10 μg/dL. It is advisable for pregnant women to avoid occupational or avocational lead exposure that would result in blood lead concentrations > 5 μg/dL. Chelation may have an adjunctive role in the medical management of highly exposed adults with symptomatic lead intoxication but is not recommended for asymptomatic individuals with low blood lead concentrations.

Family Lead Poisoning Associated with Occupational Exposure

Lead is a potent poison that affects multiple body systems. It is well documented that children under age 6 years and the fetus are especially vulnerable to neurologic damage affecting learning and behavior with potential for life-long impact. In 1991, the Centers for Disease Control and Prevention (CDC) lowered the blood lead level (BLL) of concern for children from 25 to 10 micrograms per deciliter (μg/dL) (CDC 1991).1 Efforts to reduce lead in the environment, primarily by eliminating lead from gasoline and paint, have resulted in lowering the overall geometric mean BLL for the general population in the United States from approximately 13 micrograms per deciliter (μg/dL) in the late 1970’s to <2 μg/dL by 1999 (NCHS 1984; CDC 2001).2,3 Although the average BLL has markedly declined, National Health and Nutrition Examination Survey (NHANES) 1999– 2000 data indicate that 2.2% of U.S. children aged 1 to 5 years had BLLs ≥10 μg/dL (CDC 2003).4 Recent research suggests that levels once thought safe are considered hazardous as new information emerges about lead’s harmful effects at BLLs less than 10 μg/dL.5,6 Despite success in reducing the number of children with elevated BLLs, some remain at high risk for lead exposure, including those living in homes containing lead-contaminated dust. Invisible toxins may be carried home to household members by inadequately protected workers on their clothes, shoes, or bodies, called “take-home exposure.” Documented cases of take-home exposure include lead, beryllium, asbestos, pesticides, and other toxic materials.7 In this case series, we describe take-home lead exposure incidents in California from 1992 to 2002. Lead is used in more than 100 industries. Lead dust carried from work settles on surfaces in the vehicle and home where it can be ingested or inhaled by young children with normal mouthing behavior and by household members handling workers’ clothing. Children of lead-exposed workers have disproportionately high BLLs when compared to other children.8-10 One study estimated that 48,000 families have children under age 6 living with household members occupationally exposed to lead.11 Reports of take-home lead exposure include work in mining,8,12 automotive radiator repair,13 battery reclamation,14 construction,9 and antique furniture refinishing.15

Coccidioidomycosis among Workers Constructing Solar Power Farms, California, USA, 2011-2014.

In Coccidioides-endemic areas, effective exposure-reduction measures are needed. Coccidioidomycosis and Solar Power Farms

Can Half-Day Trainings Motivate Small Contractors to Address Lead Safety?

There is a real need to educate small painting and remodeling contractors about lead-safe work practices to protect the health of occupants (especially small children) and employees. From 1996 to 2000, 34 half-day lead awareness trainings were held throughout California to increase contractors’ use of lead-safe practices. Educational methods included focusing on best practices, utilizing a peer educator, and working with stakeholders to do outreach to this hard-to-reach audience. We report on the evaluation of 18 of these seminars where we found that 30% to 49% of the interviewed contractors began doing many of the lead-safe work practices after attendance. We conclude that this program can have a modest impact in areas that contractors are more familiar with; new areas not part of their experience do not fare as well. However, without a more integrated public health educational and enforcement strategy, educational efforts such as ours can have only a limited impact.

Injuries and Traumatic Psychological Exposures Associated with the South Napa Earthquake - California, 2014.

On August 24, 2014, at 3:20 a.m., a magnitude 6.0 earthquake struck California, with its epicenter in Napa County (1). The earthquake was the largest to affect the San Francisco Bay area in 25 years and caused significant damage in Napa and Solano counties, including widespread power outages, five residential fires, and damage to roadways, waterlines, and 1,600 buildings (2). Two deaths resulted (2). On August 25, Napa County Public Health asked the California Department of Public Health (CDPH) for assistance in assessing postdisaster health effects, including earthquake-related injuries and effects on mental health. On September 23, Solano County Public Health requested similar assistance. A household-level Community Assessment for Public Health Emergency Response (CASPER) was conducted for these counties in two cities (Napa, 3 weeks after the earthquake, and Vallejo, 6 weeks after the earthquake). Among households reporting injuries, a substantial proportion (48% in Napa and 37% in western Vallejo) reported that the injuries occurred during the cleanup period, suggesting that increased messaging on safety precautions after a disaster might be needed. One fifth of respondents overall (27% in Napa and 9% in western Vallejo) reported one or more traumatic psychological exposures in their households. These findings were used by Napa County Mental Health to guide immediate-term mental health resource allocations and to conduct public training sessions and education campaigns to support persons with mental health risks following the earthquake. In addition, to promote community resilience and future earthquake preparedness, Napa County Public Health subsequently conducted community events on the earthquake anniversary and provided outreach workers with psychological first aid training.

The Role of State Public Health Agencies in National Efforts to Track Workplace Hazards and the Relevance of State Experiences to Nanomaterial Worker Surveillance

Objective: This essay examines the role state public health agencies could play in the surveillance of emerging workplace hazards including nanotechnology. Methods: This essay describes existing state occupational health surveillance programs in order to demonstrate their potential applicability, and limitations, in regards to nanomaterial worker surveillance. Results: State public health agencies have access to information and an ability to put surveillance information to use in ways that complement those of industry, academia, regulatory agencies, and federal partners. Conclusions: Some state public health agencies have significant experience with occupational health surveillance and are therefore valuable partners in the development and implementation of nanotechnology worker surveillance programs. Including states in emerging hazard surveillance enhances surveillance activities and builds state capacity to help workers.