(CNN) Afroz Shah, a lawyer in Mumbai, hasn't had a weekend off in four years. But he hasn't spent this time writing briefs or preparing for court.

His mission? Saving the world's oceans from plastic pollution.

It's a calling he found in 2015 after moving to a community in Mumbai called Versova Beach. He had played there as a child and was upset to see how much it had changed. The sand was no longer visible because it was covered by a layer of garbage more than five feet thick -- most of it plastic waste.

"The whole beach was like a carpet of plastic," he said. "It repulsed me."

The unsightly mess Shah had stumbled upon is part of a global environmental crisis. More than 8 million tons of plastic ends up in the world's oceans each year -- the equivalent of a garbage truck dumped every minute. It's predicted that by 2050, there will be more plastic in the ocean than fish.

The results are devastating. More than 1 million seabirds, 100,000 sea mammals and countless fish die from plastic pollution each year.

"The marine species have no choice at all," Shah said. "We are attacking their habitats, their food. Plastic in (the) ocean is a killer."

In October 2015, Shah began picking up trash from the beach every Sunday morning. At first, it was just him and a neighbor, and then he began recruiting others to join in. Word spread and with help from social media, more volunteers got involved.

Shah hasn't stopped since. He's now spent 209 weekends dedicated to this mission, inspiring more than 200,000 volunteers to join him in what's been called the world's biggest beach cleanup. By October 2018, Versova Beach was finally clean and Shah's cleanups expanded to another beach as well as a stretch of the Mithi River and other regions of India.

All told, the movement has cleared more than 60 million pounds of garbage -- mostly plastic waste -- from Mumbai's beaches and waterways.

For Shah, the work has always been a personal journey, but it has earned global attention. After he was honored as a Champion of the Earth by the United Nations in 2016, Bollywood celebrities and politicians embraced his mission and joined in his cleanups.

While he continues to work as a lawyer during the week, Shah now devotes nearly all of his free time to this cause. He said he believes that people must accept responsibility for society's impact on the environment.

"This problem of pollution is created by us. ... If this huge ocean is in a problem, we'll have to rise up in huge numbers."

Today, Shah is also working with coastal communities to tackle plastic pollution at one of the sources. In areas lacking sufficient waste management systems, trash often ends up in creeks and rivers that empty into the ocean. Shah and his volunteers educate and assist villagers in reducing, managing and recycling their plastic waste.

CNN Hero Afroz Shah

For years, Shah's work was strictly a grassroots effort that he coordinated on social media . Recently, he started the Afroz Shah Foundation to help spread his mission across India and around the world.

"This world talks too much. I think you must talk less and do action more," he said. "Every citizen on this planet must be in for a long haul."

CNN spoke with Shah about his work. Below is an edited version of the conversations.

CNN: You've said that beach cleaning is not just about clean beaches. What do you mean by that?

Afroz Shah: Beaches are like nets. They trap the plastic. The ocean is telling us, "Take it -- take it away." So, as the beach gets clean, the ocean is also getting clean. There's a dual purpose. Volunteers who come to pick up are also getting trained to handle plastic. Anybody who sees plastic here will not buy plastic later. They'll say, "No, no we don't want this! We had to clean up so much!' So, it's creating awareness.

Cleaning is one part, but it's not the solution. We are drowning in plastic. The bottles, packets, wrappers, packaging to preserve the food is what travels and lands (in the ocean). You have to reduce garbage in this world and change the way our packaging is made. So, it's about what you can do as a person and as a system. I tell people, "Please protect yourself and other species. Have you thought about how do you reduce your garbage?" We are a smart species. We'll adapt. We'll learn. And with these youngsters rising up, I see hope.

CNN: You're also taking your message to students.

Shah: Twice a week I go to schools and colleges. I feel the urge to be with these youngsters and train them up on plastic pollution. I'm looking at creating leaders there. I tell the kids, "You exist with other species. Your habits should not hurt the other species." The energy of these youngsters is infectious. I can see it in the eyes of those kids. They want to be the change. They want to take it up. I can see it, years from now -- some will become lawyers, judges, politicians. This will become a huge thing all over India. If those kids get it right, the world will get it right. So, my idea is to put the seed there.

CNN: Having worked on this for four years now, what's your insight into why this is happening?

Shah: There is a disconnect with Mother Nature. It's about me, me, me -- all the time. "I need a life of convenience." But we exist with other species. You cannot by your choices attack their lives and habitats. Every wrapper, every plastic straw is a war on another species. So, our choices and lifestyle need to be balanced -- all 7 billion of us.

I feel the need to do something for my planet, so this will continue for life. This is a mindset change. But this must reach every human being. What is happening with climate change, plastic pollution, climate injustice is going to hit all of us. We have 7 billion people. If each one could start -- this journey could become marvelous. Can we do it together?