K.S.Parthasarathy
Date:26/02/2009 URL: http://www.thehindu.com/thehindu/seta/2009/02/26/stories/2009022650061400.htm
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Radioactive contamination in steel: a wake-up call
Regulatory authorities have identified Indian steel products contaminated with cobalt-60 in the U.S., Germany, France and Sweden. The events occurred at disturbingly high rates.
“Overall, 123 shipments of contaminated goods have been denied entry to U.S. ports since screening began in 2003, according to Homeland Security data.
Of those, 67 originated in India, 23 came from China and 20 were from Canada” (The Los Angeles Times, November 13, 2008). We cannot ignore this wake-up call.
150 incidents
In the last three years, out of the 500 incidents, involving uncontrolled radiation sources, which the International Atomic Energy Agency (IAEA) came to know, 150 were related to sources found in scrap metal or contaminated goods.
The finding in Germany is attracting more attention. On August 19, last year customs officers identified a container of contaminated stainless steel bars from India on way to Russia. They ordered that the container be put back on the ship immediately and be sent back to India (SPIEGEL ONLINE, February 16).
There were several such findings later; The German Environment Ministry received 19 findings which included radioactive bars, steel cables, chippings and valve housings from 12 states. SPIEGEL reported that a total of 150 tons of contaminated steel has been seized.
Some of it, about 85 tons, according to a reliable source, have been sent back to India. Rest of it remains in Germany pending a decision on its safe disposal.
One of the possible practices is to use the items depending on their radiation levels in fencing or in bridges where the occupancy is less.
Imported metal scrap
After a thorough survey, the Atomic Energy Regulatory Board (AERB) concluded that the steel products in the recent incidents were made out of imported metal scrap which contained radioactive material. India imports more than 80 per cent of stainless steel metal scrap for recycling in the steel industry. Also most of the contaminated material was exported.
The health consequences from these products were negligible, as the radiation levels were low. But the presence of even low radiation levels is not desirable.
We do not have any estimate of the humongous economic losses including loss of business suffered by the industry. In some instances, the defaulters had to ship back the rejected material for safe disposal.
In spite of regulatory control, radioactive sources get lost occasionally. These may be melted along with other metal scrap. The steel products include handle bars, manhole covers, metal straps, steel wires, lift buttons, metal strips used in leather bags etc.
Sources licensed for use in India are unlikely to get into metal scrap, because of regulatory measures in place. However since there were a few instances of loss of control of sources, there is no room for complacency.
Presently, we have no firm assurance that contaminated imported scrap will not enter the country. Several measures including the plan to install radiation monitors at shipping ports through which bulk of the imported scrap metals enter the country must be implemented swiftly.
Precautions
Every importer of metal scrap should obtain a certificate from the exporting country that the scrap is free from radioactivity. A multilayer radiation check system proposed by AERB should be followed to prevent the import and export of radioactive contaminated material.
During this week, over 300 specialists from 62 countries including India are attending a five day International Conference on Control and Management of Inadvertent Radioactive Material in Scrap Metal, organized by the IAEA at Tarragona, Spain. The delegates asserted “that further steps are needed to protect people from radioactive material that can end up in junks and scrap yards,” (IAEA release, Feb 23).
All agencies must wake up before it is too late. Not long ago, explosion of live shells in imported metal scraps led to loss of life in India. Import of scrap laced with high levels of radioactivity is a possibility we must be concerned with.
K.S. PARTHASARATHY
FORMER SECRETARY, AERB
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