(NEXSTAR) – The tools you cook with may be introducing an unwanted ingredient into your family dinner: flame retardant. A study, published last month in the journal Chemosphere, tested 203 household products made of black plastic. The researchers found 85% of them contained high concentrations of flame retardant. When cooking or serving with black plastic utensils, like spatulas, tongs and ladles, the toxic materials inside can seep into your food. Heat makes the leaching occur even faster. (So you may also want to avoid heating up any leftovers in black food containers, like you might get with takeout.) Map: Does your drinking water contain ‘forever chemicals’? Exposure to flame retardants is concerning because they can cause cancer and issues with reproduction, development, the endocrine system and the brain. Cooking with any type of plastic is questionable, experts say, but black plastic is especially risky because its source is often recycled e-waste. TVs and computers are treated with flame retardant so they don't cause a house fire, the Atlantic reports, but the problem arises when the e-waste is later used to make new household items that don't need and shouldn't have flame retardant. Black plastic kitchen utensils, like the ones pictured, were found to have high levels of flame retardant in a recent study. (Getty Images) "Despite the lack of transparency and restrictions, plastics from electronics are often recycled and can be incorporated in household items that do not require flame retardancy, resulting in potentially high and unnecessary exposure," the study's authors wrote. The researchers also detected deca-BDE in black plastic kitchen utensils. It's a hazardous synthetic chemical that has been banned, but used to be used to make electronic casings. Despite being banned in 2021, it appears to still be making its way into our homes via recycled plastic. Should you set heat to a constant temperature or turn it on and off? But not ever single piece of black plastic is contaminated, biochemist Andrew Turner told the Atlantic. The problem is average people have no way to tell which of their utensils, takeout containers or children's toys are toxic and which aren't. "It’s just a minefield, really," he said. The safest option? Toss the black plastic spatulas, and replace them with silicone, metal or wooden cooking utensils.