The U.S. stock market downturn has led to a decrease in oil prices, which have dropped to a four-year low due to China's additional tariff on American goods and a potential global crisis. This decline has negatively affected vegetable oil prices, with May soybean oil futures experiencing a 4.8% drop. Other commodities such as palm and sunflower oil also saw slight decreases, despite the significant fall in oil prices. The situation is anticipated to worsen with more tariffs from other countries, and experts warn of a potential decline in commodity markets in the coming months.