GENEVA, June 13 (Xinhua) -- People's health could be improved by reducing environmental risks including pollution, hazards in the work environment, ultraviolet radiation, noise and climate and ecosystem change, the World Health Organization (WHO) said on Wednesday.

    Releasing the first ever country-by-country analysis of the impact of environmental factors on health, the U.N. agency said that 13 million deaths worldwide could be prevented every year by making environments healthier.

    New data shows that in some countries more than one-third of the disease burden could be prevented through environmental improvements. Those countries worst affected by environmental problems include Angola, Burkina Faso, Mali and Afghanistan.

    According to the data, in 23 countries worldwide more than 10 percent of deaths are caused by just two environmental factors: unsafe water, including poor sanitation and hygiene; and indoor air pollution due to solid fuel use for cooking.

    Around the world, children under five are the main victims and make up 74 percent of deaths due to diarrhea-related disease and lower respiratory infections, caused by unsafe water and indoor air pollution, respectively.

    Low-income countries suffer the most from environmental factors, losing about 20 times more healthy years of life per person per year than high-income countries.

    No country is immune from the environmental impact on health, the data showed.

    Even in countries with better environmental conditions, almost one-sixth of the disease burden could be prevented, and efficient environmental intervention could significantly reduce cardiovascular disease and road traffic injuries.

    "These country estimates are a first step toward assisting national decision-makers in the sectors of health and environment to set priorities for preventive action," said Susanne Weber-Mosdorf, WHO's assistant director-general for sustainable development and healthy environments.

    "It is important to quantify the burden of disease from unhealthy environments. This information is key to helping countries select the appropriate interventions," he added.