University of Birmingham researchers found that, on average, a fifth of the flame retardants in contaminated black plastic utensils moved into hot cooking oil. Heat is what drives chemicals out of plastic and into food.
- Authors / organisation
- Kuang J., Abdallah M.A.-E. and Harrad S.
- Year
- 2018
- Journal or publisher
- Science of the Total Environment
- Study type
- Laboratory
- Evidence strength
- Evidence: Medium
- Sample / scope
- 96 black plastic kitchen utensils bought in the UK; simulated cooking in hot oil with the contaminated ones
- Key finding
- On average 20% of the brominated flame retardants in contaminated black plastic utensils moved into hot cooking oil; skin contact passed on very little.
- Headline number
- 20% of flame retardants moved into hot oil
- Caveats / how it is misquoted
- Lab simulation of cooking with a small number of contaminated utensils; the estimated daily intake was low. Newer utensils (bought after 2011) were much less often contaminated.
- Open access
- Yes
- Verified on
- 3 October 2026
Researchers at the University of Birmingham in the UK tested 96 black plastic kitchen utensils for bromine, a sign of flame retardants from recycled electronics. Utensils bought before 2011 were far more likely to contain it (31 of 69) than ones bought later (3 of 27).
They then heated contaminated utensils in cooking oil to copy real cooking. On average, 20% of the flame retardants moved from the utensil into the hot oil. Simply handling the utensils passed on very little.
Their estimate of what people would take in this way was small, about 60 nanograms a day. The bigger lesson is about heat: it is cooking, not touching, that moves these chemicals from plastic into food.
Why it matters: if you cook with black plastic utensils, replace them with wood or stainless steel, starting with any that are old, melted or worn.