Gas, Vapor Risks and Lead Poisoning Prevention

Gases, Vapors, and Associated Risks

A gas is matter neither liquid nor solid at room temperature and normal atmospheric pressure, expanding to fill any container. A vapor is the gaseous state of a substance typically solid or liquid. Fumes result from volatilization or sublimation. Gases and vapors diffuse freely, remaining mixed with air.

Lead Poisoning

Metabolism

Inhaled lead is 40-60% retained in the lungs, entering circulation. Ingested lead absorption is about 10%. Blood lead distributes to liver, kidneys, brain, and bone. Elimination occurs via respiratory tract, gastrointestinal system (bile, feces), urine, and generalized discharges (colic).

Pathological Effects

• Hematologic: Altered metabolism via enzyme changes and metabolite accumulation.
• Vascular: Spastic action on capillaries and arterioles.
• Renal: Toxic and/or tubular effects.
• Peripheral Neurological: Neuritis in extremities.
• Central Neurological: Edema and encephalopathy.
• Smooth Muscle: Contraction of intestinal and uterine muscles.

Clinical Manifestations

Acute, subacute, and chronic symptoms vary with dose, exposure time, and compound.

• General: Anemia, low hemoglobin, pallor, headache, weakness.
• Vascular: Acute hypertension.
• Renal: Kidney failure.
• Neuromuscular: Tremor, muscle cramps.
• Brain: Seizures, unconsciousness, coma.
• Digestive: Nausea, abdominal pain.

Hygienic Control

Environmental Measures

• Local ventilation.
• Process enclosure.
• Control molten metal temperature below 500°C (thermostat).
• Wet cleaning or mechanical suction for walls and floors.
• Separate dining areas.
• Separate lockers for street and work clothes.
• Bathroom and toiletry facilities.

Personal Measures

• Preventive education.
• Appropriate work clothing.
• Personal protective equipment (respiratory protection against fumes and dust).
• Correct eating, drinking, and smoking habits in the workplace.