Since the beginning of 2025, four copper mining companies—one British and three Chinese—have been accused of causing severe environmental damage in Zambia by releasing toxic waste into the Kafue River watershed. The most devastating incident occurred on February 18 when a tailings dam at Sino-Metals Leach Zambia (a Chinese firm) burst, releasing 50 million litres of acidic effluent. The spill killed fish, destroyed crops, and harmed livestock, devastating local livelihoods. Another Chinese-owned mine, Rongxing Investments, faced accusations of acid spills and a worker fatality, leading to the arrest of its director. Meanwhile, Mimbula Mine, owned by British firm Moxico Resources, was linked to a January toxic spill that polluted water sources. A fourth company, Ozone Mine (Chinese-owned), was accused of discharging chemical waste, causing crop failures and waterborne diseases.

The spill has sparked public outrage, especially as Zambia aims to quadruple copper production by 2031 to meet global demand for electric vehicles. Environment Minister Collins Nzovu called the Sino-Metals spill a 'serious environmental disaster', blaming inadequate safety measures. A multi-agency task force has been formed to investigate and enforce penalties. Environmental groups are calling for the companies to be prosecuted, citing minimal accountability in previous incidents. The Kafue River, vital for irrigation, fishing and drinking water for millions, remains at risk. While Sino-Metals has apologised and promised clean-up efforts, activists are calling for stricter regulations and compensation for affected communities.

Six months after Sinometals caused a toxic mine spill in northern Zambia, the U.S. Embassy ordered all government personnel to evacuate the affected area in August. This was in light of new findings that hazardous substances, including arsenic, cyanide and uranium, were polluting the Kafue River system and potentially contaminating the air.

Zambia has denied that there are ongoing health risks from a toxic acid spill in its copper-mining region. This was in response to claims by the U.S. Embassy of widespread contamination, which prompted travel restrictions for U.S. officials. Government officials stated that clean-up efforts using lime had normalised pH levels and reduced heavy metal concentrations, averting immediate danger to humans, animals, and plants. While the U.S. Embassy warned of ongoing pollution of the water and soil around Chambishi, the Zambian government assured the public that the area is now safe. They also noted that the plant operator, Sino Metals Leach Zambia, is fully cooperating with the clean-up efforts.

In August 2025, a leaked report by consultant firm Drizit, commissioned by Sino-Metals, concluded the spill released roughly 1.5 million tons of toxic tailings and warned of severe, long-term health and ecological risk. Drizit was eventually fired by Sino-Metals, citing a contractual dispute. Separately, in the same month, an independent consultant working for the Finnish embassy found high levels of 16 heavy metals in the tailings. Meanwhile, affected residents and lawyers escalated from demands to formal lawsuits seeking large emergency and remediation funds, documented how interim payments required recipients to sign “Deed of Settlement and Release” waiving claims, and alleged systematic surveillance and intimidation.

In April 2025, Business and Human Rights Resource Centre invited Moxico Resources to respond on allegations regarding acid spills polluting the Kafue River. Later in August 2025, Business and Human Rights Resource Centre invited Yunnan Jinxun Resources Co Ltd to respond on allegations regarding compensation packages from their subsidiary Rongxing Investments. Both companies did not respond.