Many higher-income countries export plastic waste to lower and middle-income countries where treatment facilities are often less advanced, which therefore comes with greater environmental consequences. China was the largest importer of plastic waste until it issued the Prohibition of Foreign Garbage Imports (referred to as "the China import ban") in 2017, which drastically changed global plastic waste trade. This study uses country-level data on waste management, and trade statistics combined with high resolution sub-national population density maps to assess the effect of the China import ban on plastic waste leakage into the aquatic environment. The results are presented on a 30-arc grid (approximately one km$^2$) resolution. Global mismanaged plastic waste (MPW) generation is estimated to increase from approximately 62 Mt (million ton) in 2016 to 64.7 Mt in 2019. Around 64\% is emitted into the aquatic environment, which is estimated to increase from approximately 39.5 Mt in 2016 to 41 Mt in 2019. MPW emission into the aquatic environment from imports accounted for approximately 1.9\% of global emission in 2016 and decreased to 1.4\% in 2019, which is the result of a 43\% reduction in global traded plastic waste. Despite the substantial decrease in Chinese aquatic MPW emission from imports, other lower or middle-income countries with higher rates of mismanagement and a higher probability of emission experienced strong increases.