The government expresses official concern about the air quality in Hong Kong, but campaigners say it has never implemented the revised World Health Organisation (WHO) guidelines on the problem so it has been left to businesses to consider or ignore their corporate social responsibility in this area. A significant amount - about 27 per cent - of the polluted air is due to vehicle emissions, with 48 per cent traced to energy plants, according to Clear The Air (CTA), a pressure group launched by volunteers in 1997. It has carried out community campaigns and those targeting idling and smoky engines have been a success, with offending vehicles being reported to the Environmental Protection Department. The group is working on a proposal for a similar scheme for smoky boats. It is also acting as a non-official informer of establishments that are not complying with the latest smoking regulations - which it regards as an unquestionable breach of CSR. CTA does not believe that CSR will reduce pollution. 'Only Hong Kong government laws and regulations mandating WHO pollution levels on the power companies will have an effect,' said Mark Hunter, chairman of the CTA energy committee. 'As well as freeing and deregulating the power market to allow true competition and market prices for electricity, [it should] tax polluting power stations and offer incentives for energy efficiency and renewable energy, such as solar panels.' Mr Hunter said that long-term health damage from the worsening pollution was serious, pointing out University of Hong Kong medical professor Anthony Hedley's recent comments in the South China Morning Post, in which he said that air pollution was not just a medical issue but a societal and ethical one, and that growing up in an area with poor air quality might damage the lungs of young people.