Use

Monitor exposure to arsenic, lead, and mercury.

Arsenic

• Blood levels of arsenic have a short half-life and are useful only for monitoring recent or acute exposure. Arsenic is present in many pesticides, rodenticides, weed killers, paint, and wood preservatives.

Lead

• Hematologic consequences ascribed to lead toxicity may be basophilic stippling, mild anemia, and reticulocytosis. Other characteristics of toxicity may include increased urine δ-aminolevulinic acid, increased erythrocyte protoporphyrins, and decreased aminolevulinic acid dehydrase. Lead lines on gums or at the metaphyses of long bones in children may also be present. Early symptoms of lead poisoning include anorexia, apathy or irritability, fatigue, and anemia. Toxic effects include GI distress, joint pain, colic, headache, stupor, convulsions, and coma.
• Lead and organic lead compounds have numerous commercial and industrial applications, including paints, plastics, storage batteries, bearing alloys, insecticides, and ceramics. Exposure may also occur through the inhalation of dust containing lead emitted by automobile exhaust. A common source of lead exposure among children is through the mouthing of inanimate objects, specifically objects with paint and paint chips that contain lead. Acute lead exposure is rare; however, toxicity may occur through acute ingestion of a lead salt or acetate. Blood is the preferred specimen by which the extent of an acute or recent exposure to lead may be measured.

Mercury

• Sampling time is end of shift at the end of the work week for industrial exposure monitoring. Metals with timing “end of shift at the end of the work week” (meaning four or five consecutive days with exposure) are eliminated with half-lives longer than five hours. Such metals accumulate in the body during the work week; therefore, their timing is critical in relation to previous exposures.
• Blood mercury levels may be elevated due to the presence of inorganic mercury and/or organic mercury compound (e.g., ethylmercury and methylmercury). These alkylmercury compounds are generally not used in industry but are considered more toxic to humans than inorganic mercury.
• Acute and chronic mercury poisoning affects the kidneys, central nervous system, and the gastrointestinal tract. The three telltale symptoms of mercury poisoning are impaired articulation, irregularity of muscular action, and constricted visual fields. Mercury poisoning through chronic exposure to metallic and inorganic forms of mercury generally produces nervousness, lassitude, tremor, and mucous membrane irritation. Inorganic mercury poisoning is associated primarily with peripheral effects, including gastroenteritis and tubular nephritis, whereas organic compounds predominantly affect the central nervous system (CNS) and effects may be severe and irreversible.
• Chronic inorganic mercury poisoning is an occupational disease of smelters, mercury miners, gilders, and factory workers. Inhalation of mercury vapors may lead to pneumonitis, cough, fever, and other pulmonary symptoms. The most reliable way to measure exposure to inorganic mercury is to measure urinary mercury levels. Correlation between urine levels and symptoms is poor, however.
• The most common nonindustrial source of mercury poisoning is the consumption of methyl mercury-contaminated fish. Organic mercury poisoning is best detected in whole blood, as this form of mercury is located mainly in the RBCs. Organic mercury poisoning may develop quickly and is usually a more serious disease. Studies conducted by the CDC found that approximately 6% of childbearing-age women had levels at or above a reference dose, an estimated level assumed to be without appreciable harm (>5.8 μg/L). Women who are pregnant or who intend to become pregnant should follow federal and state advisories on consumption of fish.
• Additional general population exposure to mercury is from coal-fired power plants where an estimated 75 tons of mercury are emitted into the atmosphere each year.

BEI® are reference values intended as guidelines for evaluation of occupational exposure. BEI® represent biological levels of chemicals that correspond to workers with inhalation exposure equivalent to the threshold limit value (TLV®) of the chemicals. TLVs refer to the airborne concentrations of substances and represent conditions under which it is believed that nearly all workers may be repeatedly exposed, day after day, without adverse health effects.