Lead poisoning--a hazard of traffic and industries in Pakistan.

We measured blood lead level, hemoglobin, and urinary amino-levulinic acid (ALA) in industrial workers and in individuals exposed to vehicle smoke. Industrial workers and people exposed to traffic smoke had comparatively higher blood lead levels than the controls (p < 0.0001). Similarly, urinary ALA was 3.82 mg/dL in industrial subjects, 3.68 mg/dL in traffic-exposed people, and 0.8 mg/dL in control subjects (p < 0.001). The hemoglobin level was lower in the industrial group and in the traffic exposure group compared with the control group (p < 0.01). Traffic smoke-exposed persons, such as traffic police staff, had higher blood lead level than those handling lead material, Government Transport Service (GTS) workshop staff. The length of exposure showed no relationship with the lead levels. However, a positive correlation was observed between the duration of exposure and urinary ALA in both sample groups. The major signs and symptoms of the population studied included headache, generalized body pain, hypertension, and depression.