Shrouded in secrecy and jealously guarded by the Pakistan Atomic Energy Commission, there is little public debate about Pakistan's nuclear safety record in the wake of what is happening at Fukushima.

There are two main reactors used for energy production in Pakistan: the ageing plant on the coast near Karachi (Kanupp) and the nuclear plant near Chashma Barrage on the Indus River (Chasnupp I). Between them, they provide only about 350 MW of energy, just 2% of Pakistan's energy demand. A second nuclear reactor at Chashma (Chasnupp II) is being tested and should start operations soon. They are extremely costly, at about US $1bn for each of the Chasma reactors, plus they are very unsafe, according to two of the country's top physicists who teach at the Lahore University of Management Sciences.

"Kanupp only produces 50MW while Chasnupp I produces 300MW. Chasnupp II only came on line in March this year and will produce another 300MW as well," says nuclear physicist Dr Pervez Hoodhboy.

"The PAEC would become irrelevant without them – it is a matter of ego for them to keep the reactors going … they are nothing more than toys." Kanupp, which is under repairs, is currently being run at only 30% of its capacity. "It generates enough electricity to power just 3% of the city [Karachi]", says physics professor A H Nayyar.

To make matters worse, the safety aspect of the plant is alarming. Kanupp came into commercial operation in 1972 and has outlived its 30-year lifespan, but the PAEC – which is part of Pakistan's Ministry of Defence – has given it a 10-year extension and now intends to keep it going even longer with some repairs and replacements. "The operators working there privately say that this reactor has gone beyond its life and they are afraid that something could go wrong," says Dr Pervez, who has visited Kanupp. "The structure has been weakened by decades of radiation."

He says that the plant is only superficially monitored by the International Atomic Energy Agency, who "do not have the capacity to look at everything important in a reactor". Kanupp is located next to the Arabian Sea and in the 1990s radioactive cooling water accidentally leaked from the plant, but officials played down the incident. The spent fuel is stored onsite and should an accident occur, the devastation would be very great.

There are also several major faults around Karachi and the southern coast of the Makran, so earthquakes and tsunamis cannot be ruled out. In November 1945 there was a tsunami that hit the coast triggered by a magnitude 8.1 earthquake. Should an accident occur, the coastal winds could blow the radioactive plume over Karachi, which has grown to a population of nearly 15 million in the past 30 years and there are homes close to the reactor now. "There is the absence of a safety culture. Then there is the incapability of the authorities to deal with anything of this magnitude," says Dr Pervez.

The reactors in Chashma, though newer, are not any safer due to their location in a seismic zone. In fact, Prof Nayyar pointed out the dangers in a report he co-authored in 1999 for Princeton University's Centre for Energy and Environmental Studies (pdf). Chasnupp I and II are located on the banks of the Indus river, Pakistan's lifeline and a major source of fresh water for irrigation and domestic use.

There are several safety concerns here about the design: Chasma I was built by the Chinese on their indigenous model which proved to be quite faulty as the original, Qinshan I, developed problems with its water flows. The reactor's nuclear vessel had to be fixed by engineers from US nuclear technology company Westinghouse after being contacted by the Chinese authorities. Pakistan buys its nuclear reactors from the Chinese, because no one else is willing to sell to them. As for the Chinese, they have no other market to sell their nuclear products to, as there are far more experienced producers around such as France.

More importantly, according to Prof Nayyar: "The region is earthquake-prone and in case of seismic activity, the soil can liquify and cause a landslide. What would happen to the reactor then?" The Chasma reactors are built on sandy river shores and not on a solid rock base, as was the case with Fukushima. The PAEC claims that underneath the reactors are a five-metre reinforced concrete and cement base, which would protect reactors in case of an earthquake. But what about the water and electricity connections? They would be cut off if the base moves during seismic activity. "We shared our concerns with the PAEC and in return they did some more seismological studies, and that's it," says Prof Nayyar.

There is a regulating authority called the Pakistan Nuclear Regulatory Authority set up in 2005 by the government, but this is staffed by former PAEC officials. When contacted, the head of their information services directorate, Mohd Ali Awan, said: "Although the plants are safe as per the regulatory requirements and international standards set by the IAEA, in the wake of the Fukushima accident, the PNRA has asked the PAEC to review safety and emergency plans." However, no deadline has been given to the PAEC.

In the meantime, there is a plan by the Pakistani government to build even more nuclear reactors. According to Dr Pervez: "It is hard to understand their continued enthusiasm to acquire more reactors. By 2030 they want 8000MW of power from nuclear energy, which is an absurd goal". The government has neither the money nor the technical know-how to build two more reactors, but they are hoping once again the Chinese will help them out with credit and expertise. Pakistan's expensive nuclear toys might prove to be lethal but it seems they are to be bought at any cost.