Medical Surveillance

Fact Sheet No. OSHA 93-52

Lead Exposure in Construction

MEDICAL SURVEILLANCE

When a construction employee is occupationally exposed to lead at or above the action level of 30 ug/m(3) on any one day in a calendar year, the employee must be provided initial medical surveillance consisting of biological monitoring in the form of blood sampling and analysis for lead and zinc protoporphyrin levels. Blood lead levels are currently the best indicator of personal lead exposure. Workers potentially exposed to lead at or above the action level must be monitored for the presence of lead in the blood and the effects of lead on the blood-forming system. Full medical surveillance is to be provided to employees exposed to lead at or above the action level for more than 30 days per year. All medical examinations and consultations shall be performed by or under the direct supervision of a qualified physician and shall be provided to employees at no cost, without loss of pay, and at a reasonable time and place. A qualified physician is a doctor of medicine (M.D.) or osteopathy (D.O.) familiar with the objectives and requirements of a medical surveillance program for lead exposure.

The following conditions necessitate an immediate medical consultation including, as determined by the qualified physician, a physical examination and a blood sample for lead analysis (biological monitoring):

• whenever a worker develops signs or symptoms associated with lead toxicity; and
• before a worker restarts work following medical removal.

The purpose of biological monitoring is to identify workers with elevated blood lead levels. The data from biological monitoring is objective evidence of a worker's body burden from lead exposure, and this data can be used to follow changes in worker exposure.

Blood lead and zinc protoporphyrin (ZPP) or free erythrocyte protoporphyrin (FEP) shall be monitored for those workers exposed to lead. In general, workers in high-risk occupations should be monitored as often as needed to prevent adverse health effects.

Analysis of blood samples shall be conducted by a laboratory currently approved by OSHA. Employers should contact their local OSHA area office for a current list of approved labs.

Lead is toxic to both male and female reproductive systems. Workers who are actively seeking to have a child or who are pregnant should contact qualified medical personnel to arrange for a job evaluation and medical follow-up. Employers who have been contacted by employees with concerns about reproductive issues should refer them to qualified medical personnel.

Employers must obtain a written signed opinion from the examining physician for each medical examination performed for each employee. This opinion should contain the results of the medical examination as they relate to occupational exposure to lead and must include:

• whether the employee has any detected medical condition which would place his/her health at increased risk from lead exposure;
• any special protective measures or limitations on worker's exposure to lead;
• any limitation on respirator use;
• results of blood lead determination; and
• a statement that the employee has been informed by the physician of the results of the consultation or medical examination and any medical condition that may require further examination or treatment.

Findings of lab results or diagnoses unrelated to the workers' exposure to lead must not be communicated to the employer or included in a written opinion.

Employees should be advised by each physician of any medical condition, occupational or non-occupational, which necessitates further medical evaluation or treatment. The employer should furnish the employee with a copy of the written medical opinion.

The use of chelating drugs as a prophylactic measure (i.e., to prevent a detectable rise in blood lead) is an unacceptable medical practice. Chelation may be used by a qualified physician only for diagnostic or therapeutic reasons (that is, to diagnose or treat the signs and symptoms of severe lead toxicity).

Medical removal will protect worker health both by stopping further occupational exposure and by enabling the worker to excrete the absorbed lead naturally. With good engineering, work practices, personal hygiene, and respiratory protection practices in place, very few employees should reach the medical removal trigger level specified in the OSHA standard.

OSHA's interim final standard for lead in construction uses a medical removal trigger level of 50 ug/dl. However, some authorities believe that medical removal should take place at lower levels.

Currently, 15 states require laboratories and health care providers to report cases of elevated blood lead concentrations to their state Health Departments. A list of the states that require such reporting, contact person, and the concentration that requires reporting for each state can be found in the NIOSH Alert: Preventing Lead Poisoning in Construction Workers.

When employees are removed, or otherwise limited, they must be placed in jobs that will not result in exposure to lead at or above the action level of 30 ug/m(3). The employer may return the employee to his or her former job status when a qualified physician's medical determination is that the employee is no longer at risk from exposure to lead or when the employee's blood lead level drops below 40 ug/dl.

In the case of medical removal, records must include the following information:

• the name and social security number of the worker;
• the date of each occasion that the worker was removed from current exposure to lead;
• the date on which the worker was returned to his or her former job status;
• a brief explanation of how each removal was or is being accomplished; and
• a statement indicating whether or not the reason for the removal was an elevated blood lead level.

The employer must maintain this record for at least the duration of any worker's employment.

The employer must maintain any employee exposure and medical records to document ongoing employee exposure, medical monitoring and medical removal of workers. This data provides a base to properly evaluate the employee's health.

Employers must properly record cases on their OSHA form 200 when the worker:

• has a blood lead level that exceeds 50 mg/dl;
• has symptoms of lead poisoning, such as colic, nerve damage, renal damage, anemia, or gum problems; or
• receives medical treatment to lower blood lead levels or for lead poisoning.

In addition, employees or former employees, their designated representatives, and OSHA must be provided access to exposure and medical records in accordance with 29 CFR 1910.20.

This is one of a series of fact sheets highlighting U.S. Department of Labor programs. It is intended as a general description only and does not carry the force of legal opinion.