Study on the health effect of chrysotile on workers at AC roof sheet production facilities and users of AC roof sheet

(Hospital of Construction) – Asbestos has been known for centuries and is being used in hundreds of different types of products in industry as well as in daily life in countries around the world. With durability, insulation, sound proof and anti-friction, asbestos is now used in heat pipe, boiler cover, insulation, sound proof, roofing production etc.

In Vietnam, asbestos used in industries is mainly imported Chrysotile (white asbestos). Imported chrysotile is mainly used in asbestos cement roof sheet production. According to the report of Vietnam National Roof Sheet Association, at present with an average output of about 90 million m2/year, asbestos cement roof sheet factories have the annual consumption of about 52,000 tons of Chrysotile (White asbestos).

To contribute to the assessment of the chrysotile material’s effects on human health, following the guidance of the Deputy Prime Minister in Official Dispatch No. 5313/VPCP-KGVX dated July 16th 2014 of the Government Office, the Hospital of Construction has conducted the study “Researching the effect of chrysotile on the health of workers in manufacturing units and users of asbestos- cement roof sheets”, with the following objectives:

1. Surveying the state of the labor environment and management of occupational safety and health in AC roof sheet manufacturing establishments.

2. Researching the state of occupational health and diseases of workers at AC roof sheet manufacturing establishments.

3. Providing a quick assessment of the health of AC roof sheet users in Tan Trinh commune, Quang Binh rural district, Ha Giang province.

A total of 2,559 chest X-ray scanner and 180 CT scanner were used for suspected cases, including 2,459 workers working directly in the AC roofing production line and 100 retired workers. The X-rays scanning was conducted according to the occupational disease diagnostic criteria; the results approved by the X-ray Film Council with the participation of leading experts in occupational diseases are as follows:

–  There were 2,421 cases showing normal results accounting for 94.6% of which the normal rate was 95.4% for current workers and 75% for retired worker.

–  There are 93 cases of lung calculus and fibrosis, pulmonary infiltrates due to tuberculosis, old inflammation or new progression, accounting for 3.6%.

–  No case of asbestosis is found.

–  02 cases, accounting for 0.1%, show the image of occupational silicosis lung disease with 0/1p ILO category.