Cotonou suffers from a longstanding problem of uncontrolled waste disposal and resulting environmental contamination. Most of the city’s waste ends up at informal dumpsites across the city or in the waters of Lake Nokoué, the lagoon, and the sea, where the shores are now widely covered with garbage. Waste overflows have led to severe pollution and health risks, including an increase in water-borne diseases, damages to fisheries and biodiversity, and the clogging of sewers with solid waste. Especially slum areas of the city, such for example Vèdeko, have been become increasingly converted into dumpsites. New slums are informally built at some of the wastelands along the lagoon and the Ouémé River.  Water is contaminated by leachate from waste that has increasingly piled up over the last three decades, decomposing organic waste, and toxic and even radioactive substances and heavy metals (such as lead, mercury, iron, zinc, and copper) from electronic waste and discarded batteries. The contamination has caused the spread of illnesses and epidemics, entered the food chain, and also led to a drastic decline in fish in Lake Nokoué, where the amount of fish has almost halved within just a couple of years, making it no longer possible for many fishers to make a living. Much of the waste also stems from Dantokpa Market, one of the largest markets in West Africa and trading point for all sorts of goods. Although the dumping of waste is officially prohibited, merchants say they have nowhere else to discard the waste. 
Cotonou currently generates between 700 and 800 tons of waste per day, of which only about 100 are brought to the landfill in Ouèssè (located in the commune of Ouidah), while the rest is discarded largely without any control . In light of the rising contamination levels, the municipality said it was lacking resources to handle the waste properly while the government of Benin in 2017 announced new plans to improve waste management. This should include improvements in collection and infrastructure funded by the World Bank, which already over the past decade has attempted to improve sanitation and the sewage system. Waste collection is left to many small NGOs that are coordinated through a body called COGEDA, which is linked to the municipality. However, a large waste collection point built with international funding was reported to have been constantly overfilled and inoperative since 2016. An NGO worker in 2018 explained that slum dwellers constantly suffered from waste-related illnesses and that problems had aggravated in the previous two years as private collection services stopped operating in the poorer parts of the city, for reasons that remained unexplained to them. 
The deficiencies in Benin’s waste management sector became tragically apparent in 2016 when an explosion at a landfill site 40 kilometers outside Cotonou killed at least 18 people and leftover 90 people seriously injured . The Tori-Avamé landfill had been receiving different sorts of toxic and hazardous waste that were usually burned. On the day of the tragedy, a company dumped highly inflammable spoiled flour. Hundreds of people, many of them living in extreme poverty and regularly coming to the site to scavenge through some of the waste, came to gather flour but were hit by the explosion. Environmental groups in the following pointed to the disregard of safety standards related to incineration of hazardous material at the site and, shortly after, three officials became suspended for alleged negligence.  Locals stated that many of those who come to work at the dump are aware of the risks, but have no other choice. They could earn up to 100,000 francs a month (about 150 euros; more than the double minimum income) by collecting food leftovers and electronic appliances. 
Despite these aggravating problems, informal recyclers recover a notable part of the discarded waste and have organized in several groups across Benin. In Cotonou, the largest and best-known ones are the women waste pickers of ‘Association de Femmes Recuperatrices du Benin’, created in 1997. The association drew on women’s longstanding practice of collecting household waste to make a living and had the specific aim to form a structure for collecting recyclables and improving their lives and recognition. They are today widely known as the ‘gohotos’ as they started as bottle collectors in the streets, where they typically shout “goxoto wa loo” (which in Fon means ‘empty bottle buyers are here’). They buy 70 different types of glass and plastic bottles, often from poor people, and have subsequently included more waste pickers into their activities. The association is membership-based, has a permanent bureau and monthly meetings. As of 2012, it had about 1,000 members, of which about 400 were bottle collectors while others, so-called ’gbobetoos’, picked waste in the streets, at dumpsites, or in door-to-door collection from households. It is reported that about 70 percent of the population of Cotonou benefits from their informal services. 
The process of organizing and capacity-building of the ‘gohotos’ was accompanied by Oxfam-Québec which has been involved in municipal waste collection and supported community-based recycling initiatives in Benin. Between 2001 and 2008 it worked closely with the women's association and provided basic education and entrepreneurship capacity-building, constructed a new recycling center (after the old one had burnt down), a composting project, and installed stands for waste collectors at the Dantopka market, where some of them received official accreditation to recycle. The market is not only the main site for waste collection but also the most important trading point for recyclables. Gohotos typically sell about 1,000 bottles a day to different beverage companies, including some abroad, but also recover substantial amounts of plastics, cardboard, cans, and glass – an estimated total of seven tons of waste daily.  In 2008, a cooperative was formed and members of the group engaged in dialogues with international waste picker groups with the support of the organization Women in Informal Employment: Globalizing and Organizing (WIEGO) .
The association reports of a number of ongoing challenges - above all, a lack of support from the municipal government, which, as they claim, is against them and does not acknowledge their work. The group regularly meets with local authorities but says that they are unhelpful and regularly ignore decisions, even though waste pickers pay a monthly tax. Their work remains informal which leaves them without health insurance and social protection, or access to credit or child care programs. They also continue to lack adequate workspace, access to water and electricity, and basic equipment such as gloves, boots, masks, shovels, pushcarts, and baskets.  Despite these obstacles, women waste pickers report that joining the association has helped them to find community and some form of self-help groups, which has reduced their vulnerability . Some also noted that waste collection had a long tradition in their families as also their mothers and grandmothers had already worked in recycling .