Suriname’s National Environmental Authority (NMA) has identified a one-time, unauthorized discharge of toxic chemicals as the leading hypothesis for the unexplained mass fish die-off first reported in the Saramacca River last week, according to preliminary investigation results shared with the country’s National Assembly on 30 June.
Oil, Gas and Environment Minister Patrick Brunings updated lawmakers on the ongoing investigation, confirming the NMA would issue an official press statement on the initial findings — which were first published early to the NMA’s Facebook page, which counts just 3,500 followers, before being distributed to general media outlets.
Water samples collected on 25 June and analyzed by Suriname’s FILAB laboratory detected trace amounts of cyanide and mercury, but both toxic substances were measured at concentrations below the country’s official regulatory safety limits. NMA officials note that these results do not rule out an earlier cyanide exposure event, because the compound breaks down and dilutes rapidly in natural freshwater environments, meaning concentrations could have dropped to safe levels by the time samples were collected.
Testing did find significantly elevated levels of iron, aluminum, manganese, total suspended solids (TSS), and chemical oxygen demand (COD) — a key metric that measures the overall level of organic and chemical pollution in a water source. These anomalies support the NMA’s working theory that a single uncontrolled chemical spill triggered the mass fish mortality. All preliminary findings have already been shared with the National Coordination Center for Disaster Management (NCCR) to coordinate response efforts.
Investigators are still awaiting results from analysis of fish tissue samples being processed by the national Fish Inspection Institute (VKI), which will confirm whether dead fish were exposed to harmful concentrations of contaminants. To pinpoint the exact cause, the NMA has launched an expanded, intensified round of testing: a second set of water samples was collected on 29 June, and results from that round are still pending. A more comprehensive sampling effort is scheduled for 2 July, which will include capture and testing of living native fish species from the river to either confirm or rule out ongoing contamination. A definitive final conclusion will only be published once all test results are compiled, the authority says.
Despite the partial results, NMA has stressed that the urgent precautionary advisory issued earlier for communities along the Saramacca River remains fully in effect. Local residents are still strongly urged to avoid consuming any fish caught in the affected stretch of the river, refrain from using river water for drinking, cooking, bathing or washing clothes, and avoid swimming in the water.
The NMA says it will continue to closely monitor water quality and the overall situation alongside the NCCR, national regulatory authorities and local traditional governance bodies. The public will receive immediate updates as new test results become available.