By Mark Kinver
Science and nature reporter, BBC News
Santos and his band Massukos have performed around the world
A Mozambican musician who campaigns for clean water and sanitation has been awarded a top environmental prize.
Feliciano dos Santos won a Goldman Environmental Prize for using his music star status to raise awareness about health, water and HIV/Aids issues.
The UN says diarrhoeal diseases kill an estimated 1.8 million people each year.
Santos will receive his award, described as the Nobel Prize of grassroots environmentalism, on Monday at a ceremony in San Francisco, US.
"I started using music when I realised that it was a good way to send a message and bring people together," Santos told BBC News.
"Even when you play a loud radio, people are drawn to it. Even when it plays sounds that are not about dirty water, they just want to listen to the sounds.
"I realised that music had this power, so for this reason we thought it would be good to mix it with what we wanted to achieve."
Power of music
The 43-year-old's motivation was fired when he was young because he grew up in the northern province of Niassa surrounded by poor sanitation and dirty water.
Massukos' song about latrines helps raise awareness among villagers
In 1992, shortly after he had formed his band called Massukos, Unicef was running a project to promote slab latrines.
"We decided to release a little song to promote the slabs. The lyrics were: 'Mothers, listen to me; grandmothers, listen to me, she doesn't listen to me. The slab is so good; the slab is easy to clean'."
As a result of the song, the demand for the latrines soared and the project struggled to cope with the number of people who wanted to get hold of one.
The success of the song prompted Unicef to approach the band to see if they would be interested in working for the project.
"I said no because we thought instead of doing this for Unicef, why not do this as a double project and use music to promote hygiene and sanitation," Santos recalled.
Santos says music gets his message across while people enjoy themselves
In 1996, he set up his own NGO called Estamos, which encouraged villagers in Niassa to improve their living conditions through better sanitation.
By using music, the group sang about ways to keep a clean, healthy home; and helped people understand how poor sanitation had an impact on things like water and food supplies.
Estamos promoted low-cost, environmentally friendly sanitation that composted human waste into fertiliser.
Families that used the system reported fewer diseases, while the soil produced enough crops to not only feed everyone but left a small surplus that could be sold.
Wanting to build on the success, Santos explained how he seized opportunities to get his message across to a wider audience, even if it meant disregarding official protocol.
Poor sanitation affects water supplies, which in turn spreads diseases
"A few years ago, I was trying to launch a 'wash your hands' campaign.
"I sent a letter to the president to ask him, when he visited my province, if he would wash his hands and tell others to wash their hands too to have good health.
"But I received an official letter of rejection, so I sent more letters but they were rejected, too."
Eventually, Santos had a chance to put his request directly to the president himself when the band performed at an official dinner.
"I just told him that I did not want any money, I just wanted him to wash his hands," he explained.
"The guys who rejected my letters were also there and they just glared at me. But I had the microphone, so no-one could stop me that time!"
Crop harvests have increased where farmers have used human compost
His efforts were rewarded because the country's prime minister came to his province to launch the nationwide awareness scheme.
He said that he even managed to persuade the nation's top politician to sing one of his songs.
"The song contained the line 'wash, wash your hands', and the prime minister said to the people that if they wanted good health then they should listen to the lyrics; I was so proud."
Modestly, Santos said the $150,000 (£75,000) prize money would not change his life but it would help focus attention on what was happening on the ground in Mozambique and Africa.
"It shows that even if you live in poor places, such as Niassa, you can have an influence on the world.
"Let's not talk about the money, let's do things that can change the world. Don't think about awards, think about quality of life.