NATCHEZ — A boat made up of recycled materials — including 800 plastic bottles — is keeping five men afloat on their 2,400-mile adventure down the Mississippi River to the Gulf of Mexico.

The modern-day Huck Finns are part of a group called Recycled Mississippi. The group stopped briefly in Natchez Sunday and plans to leave this morning.

They have been collecting samples of micro-plastics that they will send to Louisiana State University for further research. Micro-plastics are really small particles of plastic that degrade over time and can travel through waterways and end up in oceans.

“We’re consuming plastics without even knowing they exist,” filmmaker and producer Gary Bencheghib said. “Micro-plastics can end up in the food we eat from the fish we consume.”

While on the expedition, the group has also been picking up bottles as they float on the surface of the river or along the sandbars. They have added some of those materials to their boat.

“One of the things we’re trying to show in the expedition is the physical route plastic pollution takes on our waterways,” Bencheghib said.

Expedition Leader Dan Cullum said the Mississippi River was chosen because of its length, iconic status and the opportunity to meet people along the way. The group’s mission is to make a documentary on the pollution along the river and how it has affected the surrounding communities.

Cullum said the welcome in Mississippi has been very warm.

“Both from meeting people in local communities and people involved in protecting the river, it’s been a fruitful journey,” Cullum said.

Recycled Mississippi team members said they have met several people, including a fisherman with more than 50 years experience to activists who have almost died on the river and made the river their life. They have also met the oldest man to paddle down the Mississippi.

“It has been such an amazing experience and (shows) us that we have a community that cares so much about protecting our planet. It really gives us hope,” Bencheghib said.

The group found that the lower portion of Mississippi has been more polluted than the upper. The crew said some things Natchezians can do to help include using reusable bags and bottles and joining a community cleanup. Buying in bulk and using steel or bamboo straws also can help, team members said.

The group plans to finish up in mid-August and submit their film to various film festivals. The documentary will be free for students and teachers for educational purposes.

The film is scheduled to be released in early 2017. Weekly updates from the group are posted on www.recycledmississippi.org.