Tokyo's well-kept streets may not be the most obvious place to do it, but competitive litter-hunters sifted through the Japanese capital in their first world championship.
The Spogomi World Cup saw 21 countries battle it out to collect the most rubbish within a set time limit, scouring the streets in search of plastic, cigarette butts and other trash.
Spogomi founder Kenichi Mamitsuka started to pick up litter on his morning runs and realised that setting targets could turn it into a fun activity.
He organised his first competition 15 years ago, taking the title from the words "sport" and "gomi" - Japanese for rubbish.
He said watching the event's maiden world championship was "like a dream", but he optimistically believes it can grow to an even bigger scale.
"If you form national spogomi associations, my ambition is that it could become an Olympic demonstration event," he told AFP in front of a portion of the almost 550 kilos of rubbish collected by participants.
Armed with gloves, metal tongs and plastic rubbish bags, each team of three roamed a roughly 5sq/km collection area in Tokyo's bustling Shibuya district.
Running, ransacking existing litter bins and shadowing other teams were all forbidden, with each team followed by a referee to enforce the rules.
In both of the morning and afternoon sessions, they had 45 minutes to hunt out rubbish and another 20 to sort it into categories.
Points were awarded based on volume and type, with small items such as cigarette ends scoring highly.
Australia's Petrya Williams said that her team had "found some great spots that are like treasure maps".
"I think we've got it for the next round, we know where to look," she said, as she and her team-mates waited to weigh their haul.
Good habits
Each team had to earn the right to represent their country in Tokyo by winning national competitions.
Reasons for their involvement varied. Australia's Jamie Gray said his team belonged to a meditation group and "clean-up is part of our philosophy".
France's team arrived with something of an advantage - all three members work in the refuse collection industry.
"We have a flair for it," said Usman Khan, 32.
At the end of the day, Britain were declared the winners after collecting 57kg of rubbish.
South Africa's Philippe Louis de Froberville said Tokyo's relatively clean streets made it "harder to find the rubbish than in the competition back home".
But he believes competitive collecting can "get really big", and thinks schools are a good place to start.
"That's where you're going to get your people," said the 33-year-old from Durban, who says his passion for surfing and the ocean got him involved in collecting rubbish.
"If you start when you're young, you're going to want to do it when you're older and you're going to want to look after your environment."
Spogomi founder Mamitsuka believes changing the way people think about rubbish is key.
He says that people thought he was "making fun of activities that contribute to society" at first.
But then he began to hear stories about people getting involved and passing on good habits to their children.
"It made me think that I should keep going," he added.
"Our target is to have spogomi events in 50 countries by 2030."
