Greenpeace took the consoles and controllers apart
Sony, Microsoft and Nintendo are not doing enough to eliminate potentially harmful chemicals and metals from their games consoles, Greenpeace has said.
The body examined materials used inside the Sony PlayStation 3 (PS3), Microsoft Xbox 360 and Nintendo Wii.
Greenpeace said that while all three machines complied with European laws, the consoles still contained harmful materials that "needed to be replaced".
Nintendo's environment policies were "non-existent", Greenpeace added.
"Nintendo doesn't have any environmental policies, " said Zeina Al-Hajj, Greenpeace's International Toxic Campaign co-ordinator.
"We were shocked with Nintendo; it was our biggest surprise."
Nintendo is ranked at the bottom of Greenpeace's global assessment of "green" technology companies.
"Recently they added a list of certain commitments they have, which purely comply with legislation," said Ms Al-Hajj.
The organisation has called on all technology firms to take immediate action to eliminate toxic chemicals from products.
The report found that the PS3 and 360 both contained "very high" levels of chemicals, called phthalates, which are used to "soften" flexible materials like wires and cable coatings.
They are not permitted in toys sold in Europe but under EU regulations games consoles are not classed as toys.
Ms Al-Hajj said: "We see a gap there. For us this is still a toy.
"And whether or not it's a toy, we do not want these chemicals in our products."
The report found that all three consoles contained varying levels of the toxic element bromine, which is used as a flame retardant.
The presence of beryllium was found in both the PS3 and Xbox 360. The element is not banned under EU law but it has been linked to lung cancer when dust and fumes are created through some recycling processes.
A Nintendo spokesman told BBC News: "We fully comply with all the necessary EU Directives on the Restriction of Hazardous Substances aimed at environmental protection and consumer health and safety.
"Furthermore, in order to ensure our products are safe for use by young children we also take into consideration the standards applicable to toys."
According to the United Nations Environment Programme 50 tonnes of hazardous e-waste is generated every year.
Greenpeace said it was concerned that there was no "safe way" to dispose of old consoles and called on games console makers to introduce return and recycle policies.
A spokesman for Sony said the firm had joined with other companies, Braun, HP and Electrolux, to establish the European Recycling Platform.
The consoles were dismantled at Greenpeace Research Labs at Exeter University
Microsoft has committed to eliminating the use of polyvinyl chloride (PVC), which includes phthalates, and brominated flame retardants (BFR) by 2010.
Nintendo has also committed to removing PVC from future products, but has not given a specific timeframe.
The Nintendo spokesman said: "We have endeavoured to eliminate the use of PVC by replacing it with other materials and other methods.
"However, we continue to use PVC in certain products such as AC adaptors, within the scope of regulations from the viewpoint of ensuring safety."
Greenpeace criticised Sony for failing to agree to eliminate PVC and BFR from its games consoles, while at the same time pledging their removal from its mobile products.
Ms Al-Hajj said: "Sony has a very good record in our ranking guide. They have committed to eliminating these chemicals from mobile devices.
"But why are we finding them in such high percentages in a console? This is a tool used by children in our homes.
"None of these chemicals exist in Sony's Vaio laptop. So if they can do it for a laptop, why can't they push this for the console also?"
A spokesman for Sony told BBC News that the company would eliminate PVC and BFR from all of its products "as and when we are satisfied that we can produce products of equal Sony quality in all regards using new alternative materials".
Ms Al-Hajj said the electronics industry needed take more responsibility.
"This is one of the most innovative industries we have on the planet.
"This is an industry that is changing our way of life and if it does not take these challenges upon themselves to be more green, we are going to be in deep trouble very, very soon.
"It is not enough just to comply with the law for such an industry."
She said the European Union's Restriction of Hazardous Substances (RoHS) directive was not strong enough.
"RoHS is not enough now to control the electronics industry.
"If they are pushed to putting the environment as the priority the electronics industries will come up with alternatives because they are technically capable."
No-one from Microsoft was available for comment on the findings of the Greenpeace report.