Friday, March 23, 2012

malaysiakini: Lynas: Scientific doubts and popular will..... by Prof. Chan Chee Khoon


Lynas: Scientific doubts and popular will
Prime Minister Najib Abdul Razak has declared that “the government will not allow the Lynas rare earths plant in Gebeng, Kuantan, to operate if scientific evidence proves that the plant is harmful to people’s health and the environment” (Malaysiakini.com, Mar 22, 2012).
Central to these discussions are the ‘safe thresholds’ of 1 mSv/year (public) and 20 mSv/year (occupational) that Dr Che Rosli Che Mat (Hulu Langat MP), Dr Looi Hoong Wah (Kuantan physician), Lynas, AELB, and IAEA have repeatedly invoked.

These ‘safe thresholds’ are derived from the International Commission on Radiological Protection (ICRP) risk models which are currently under critical scrutiny and challenge, in the wake of excess childhood leukemia near nuclear power plants that can’t be explained by radiation exposures which are much below the ‘safe thresholds’.

Most recently, two large epidemiological studies in Germany (KiKK, 2008) and France (Geocap, 2012) have reported statistically robust findings of a doubling of leukemia risk for children living less than 5km from a nuclear power plant, where radiation exposures were much below the 1 mSv/year ‘safe threshold’.

Could the excess leukemia be due to inhaled or ingested radioactive particulate (internal emitters) not satisfactorily accounted for in ICRP’s risk models?

Opinions of UK panel members
(ICRP’s quantitative risk models were calibrated against external sources of irradiation, most importantly, the Hiroshima/Nagasaki atomic bomb blasts along with their long-term effects on survivors).

A UK expert panel (2004, www.cerrie.org) could not arrive at a consensus regarding the health risks of low level exposure to these internal emitters.

Opinions among the UK panel members ranged from negligible adverse effects to an underestimation of risk by at least a 100-fold.

Could the excess leukemia be due to electromagnetic radiation from high voltage power cables linked to the nuclear power stations? Or to population mixing and vulnerability to infectious agents suspected of causing leukemia? (Kinlen hypothesis).

Nobody can be sure at this point. While most sides agree that there is excess occurrence of childhood leukemia in the vicinity of nuclear power plants and nuclear reprocessing facilities, there is much less consensus on the likely cause(s) of these excess leukemia.

Even as the scientific and research community continues their debates over this, Angela Merkel has bowed to the popular will (and to the precautionary principle) to phase out nuclear power plants in Germany.

Will Najib and the Malaysian government likewise allow the popular will to prevail in Kuantan, where the safety of Lynas operations is similarly contestable?

Beyond the scientific evidence (and its currently ambiguous status), the prime minister is also aware that the collateral damage on the local economy and on livelihoods in Kuantan-Kemaman, driven by the community’s risk perception and its risk aversion, cannot be simply wished away.

Chan Chee Khoon is attached to the Center for Population Health Dept Social & Preventive Medicine Faculty of Medicine, University of Malaya.

No comments: