The two corrosion inhibitors traditionally used in coatings, red lead and zinc chromate, are toxic compounds with a variety of adverse health effects. Because they are so effective in their corrosion inhibiting capacity, many structures carry red lead- and zinc chromate-containing paints. As these structures age and are repaired or demolished, the coatings are disturbed triggering a host of regulatory requirements. This paper briefly outlines the major health effects of lead, zinc, and chromium, the U.S. regulations believed to be applicable to most projects involving in-place paints containing red lead or zinc chromate, and the liability issues that may affect such projects.
Red lead (PbO2 2PbO) and zinc chromate (various formulas based on ZnCrO4 ) are traditionally added to paints to inhibit corrosion of steel structures. Constituents of these pigments?namely, lead, chromium, and (at high concentrations) zinc?are toxic to human tissues, having both acute and chronic effects. Many structures in service carry coatings that contain red lead and zinc chromate. As the structures age and coating abatement or structure renovation or demolition is undertaken, the paint, and its constituent inhibitors, are disturbed making the activity subject to numerous federal regulations, In addition, most of these projects (typically involving a facility owner, a contractor, and several subeontractors) raise numerous questions about who is liable for ensuring regulatory compliance.
This paper outlines some of the major health hazards of zinc, lead, and chromium; describes some of the federal regulations most likely to be applied to projects involving the disturbance of paints containing red lead or zinc chromate; and discusses legal liability issues that can affect such projects.
TOXICITY
In occupational settings, three major routes of entry from exposure to toxic materials are of interest: inhalation, ingestion, and dermal. Each may be, although not always, associated with distinct effects. Also vital to assessing the impact to health are the level and duration of exposure.
The potential effects of overexposure to lead, zinc, and chromium and their compounds are summarized in Table 1; the text highlights those effects most pertinent to paint-disturbing operations and the types of exposure expected.
Lead
Lead is a poison. Occupationally, it is taken into the body primarily by inhalation and ingestion; uptake through broken skin is also possible. Lead usually passes from the respiratory and gastrointestinal system into the bloodstream, where it is transported throughout the body. The means by which the lead enters the body is immaterial in terms of its effects. What is significant is the blood lead level (BLL). When blood levels are excessive, lead has significant adverse effects on the nervous, hematological, cardiovascular, renal, reproductive, and gastrointestinal systems. 1
Nervous System Effects. Acute exposure to lead can cause acute brain dysfunction, resulting in seizures, coma, and/or death. Chronic exposure can have similar effects: severe headache, convulsions, coma, delirium, and death may occur. Other symptoms may include dullness, irritability, poor attention span, muscular tremor, memory loss, and hallucinations. Studies have shown that lead-exposed workers may have increased numbers of work-related accidents, poorer motor speed/manual dexterity with the nondominant hand, increased levels of interpersonal conflict, paresthesia in the lower limbs, weakness of the upper limbs, and other symptoms of necrologic impairment.
Cardiovascular System Effects. Both occupational and general population studies have tried to fin
