‘Regrettable substitution’: ‘high safety’ plastics chemical linked to lower birth weight

The study, which analysed data from more than 6,600 pregnancies in the National Institutes of Health Environmental influences on Child Health Outcomes (Echo) Program, found that up to 70% of women showed the chemical DINCH in their urine. Higher exposure levels increased the risk of a child being classified as “small for gestational age”, below the 10th percentile for babies born at the same stage of pregnancy. Each tenfold increase in DINCH exposure was associated with a 27-gram reduction in birth weight. An average newborn weighs about 3,400 grams (about 7.5 pounds).

The chemical, formally named 1,2-cyclohexane dicarboxylic acid diisononyl ester, saw increased use after US and European regulators began taking action over toxic phthalates such as DEHP. Industry claimed DINCH was a “high safety”, nontoxic alternative. It is used in soft plastic food packaging, cling film, plastic wine corks, children’s toys, medical devices, some textiles and flooring. German chemical giant BASF is among its major producers; global production volume jumped from 25,000 tons in 2002 to 400,000 tons in 2024.

However, the new paper is the first to link DINCH to lower birth weights and shorter birth lengths. The authors wrote that fetal growth problems can raise the risk of heart disease, learning difficulties, obesity and other issues that can echo into adolescence and adulthood. Previous research on animals and human cells has found that DINCH by-products can interfere with the hormones that guide fetal development and may trigger inflammation affecting how nutrients and oxygen reach the baby.

Leonardo Trasande, a lead author on the NYU paper, said: “Chemicals should be properly tested for their safety before they become a widespread exposure for unwitting people in the general public.” He said the findings raised “pretty serious concerns about regrettable substitution”. The source describes this as a pattern in which industry replaces one dangerous chemical with a similar compound that has comparable health risks, resetting the regulatory and research process.

Hispanic mothers or those with lower education levels were more likely to have children affected by DINCH, the study found. Researchers with the Switzerland-based Food Packaging Forum, who are currently conducting health research on DINCH, have expressed concern about the lack of health information around the chemical. There is evidence that it migrates from food packaging into food, and levels in the EU population have been increasing in recent decades.

“These results underscore the need for stronger oversight of chemicals used in food packaging and other household products by requiring they be tested before they are introduced to the market, instead of after they are connected to health concerns,” Trasande said, noting that the plastics treaty under negotiation at the United Nations is an opportunity to establish better policies. Women can protect themselves and their children by buying plastic-free products where possible, including clothing and toys, and by looking for food in glass packaging and using glass or wood storage and utensils in the kitchen.