Aplastic Anemia Due to Exposure to Benzene in Diamond Workers in Surat (India).

Benzene, used as a solvent in many industries is a known carcinogen which can lead to variety of hematological manifestations, like macrocytic anemia, aplastic anemia, myelodysplasticsyndrome and leukemia. However benzene induced aplastic anemia in diamond industry has not been reported so far in literature. We report series of cases of aplastic anemia from a single diamond factory, in Surat, India. All cases were diagnosed in June and July 2005. Benzene was used to remove whitener applied on diamonds before cutting them by Laser technology (Sarin technology from Israel). Diamond workers used benzene without any protective measures. Each worker used to clean about hundred diamonds daily by taking benzene in their hands. Most of the workers were using benzene for more than one year. The working environment used to have strong smell of benzene, however exact level of benzene in ppm was not determined. Out of 37 workers working in eight hour shift in a closed airconditioned room, eleven of them developed blood dyscrasia. Initially four patients presented with fever and pancytopenia. After confirmation of aplastic anemia in all of them remaining workers from same factory and other diamond factories using benzene were screened. From the same factory seven more cases of mild aplastic anemia were detected. Few cases of mild blood dyscrasia were detected from other diamond factories too. All cases were thoroughly examined clinically & investigated to rule out other causes of pancytopenia. Biochemical tests, liver functions, serum Iron, B12 study, tests for PNH, bone marrow aspiration & trephine biopsy and cytogenetics in severe cases were done. Three cases were treated with ATG and cyclosporine transfered to state capital, Ahmedabad. One patient died during treatment and two recovered. Two other cases were treated with cyclosporine alone and both of them recovered. No cases of MDS or leukemia detected from same factory so far. Since July 2005 benzene is no more used in diamond industry in India. After removing the workers from the exposure all other cases recovered. A close follow up for one year showed no recurrence or progression.