Dynamic changes and early warning of peanuts aflatoxin B1 contamination in China in the context of climate change

Aflatoxin contamination is a major food safety concern and has a particularly negative impact on peanuts. Climate conditions are known to influence the natural occurrence of mycotoxins; however, the specific impacts of climate change on the prevalence of aflatoxin remain poorly understood. In this study, we analysed a national-scale dataset comprising 17263 records of peanut aflatoxin B₁ (AFB₁) contamination in China from 2009 to 2022. Our results revealed that the occurrence of AFB₁ contamination in 2017 and 2021 significantly increased compared with that in 2009. The key climatic drivers included nighttime temperature, wind speed, and precipitation. Notably, temperature variations explain 49.46% of the observed increase. In a high-emissions scenario, future projections estimated that AFB₁ contamination would reach 15.06 μg·kg⁻¹ by the end of the century, representing a 8.50% increase relative to the current level. In 2022, the AFB₁ level in approximately 478,400 metric tons of peanuts exceeded the regulatory limit, and the amount was projected to rise to 1.16 million metric tons by 2100. These results underscore the urgent need to enhance aflatoxin surveillance and develop proactive strategies to mitigate aflatoxin contamination under accelerating climate change.