Plasticiser study: Overview
- Prenatal exposure to the plasticiser DINCH was linked to lower birthweight and a higher risk of babies being small for gestational age
- Researchers found a tenfold increase in a DINCH metabolite was associated with a 27.43g reduction in birthweight
- DINCH is widely used in food packaging as a replacement for phthalates, which face longstanding health concerns
- The study does not prove causation but raises questions over the safety of phthalate alternatives
- Manufacturers should monitor emerging evidence as regulators increasingly assess food-contact chemicals and cumulative exposure risks
Prenatal exposure to a commonly used plasticiser in food packaging is associated with a decrease in birthweight, according to a new study.
The chemical, known as di(isononyl) cyclohexane-1,2-dicarboxylate (DINCH), makes plastic softer and more flexible. It’s found in food packaging, as well as flooring, toys and medical devices. For food packaging, it’s generally found in softer packaging such as cling film, as well as plastic wine corks.
The study looked specifically at the effects of prenatal DINCH exposure on birthweight, birth length and gestational age, and found that a tenfold increase in a DINCH metabolite, MCOCH, in pregnancy was associated with a decrease of 27.43g in birthweight. Stronger associations were found for third trimester DINCH exposure with birth outcomes.
Overall, prenatal urinary DINCH metabolites were associated with greater risk of small for gestational age and lower risk of large for gestational age.
No association was found for a change in gestational age.
The study, carried out by New York University Langone Health, used data from the large, diverse cohort of The National Institutes of Health Environmental influences on Child Health Outcomes (ECHO) Program, which “aims to identify environmental and preventable origins of low birthweight, preterm birth, and other effects on child health and development”. It includes women from a range of ethnicities and the mean age was 30.3.
The findings do not prove causation, and the authors acknowledge that interpretation of the findings is subject to limitations, including the possibility of unmeasured confounding, but they suggest that further research is needed. “Further studies should examine joint exposures to DINCH, tere- and orthophthalates, and repeated measures across pregnancy.”
They also expressed concern about the potential consequences of growth restriction in the longer term, such as cardiovascular disease. “Associations between DINCH metabolites with fetal growth restriction raise potentially serious concerns about potential longer-term consequences … The ECHO program is well-poised to follow this cohort of children longitudinally and assess whether these downstream risks emerge.”
Why was the study done?
DINCH was introduced as a safer alternative to phthalate plasticisers in 2002. However, “a limited toxicological literature suggests that DINCH metabolites disrupt sex hormones and promote oxidant stress known to contribute to adverse birth outcomes, and epidemiologic studies have also been limited in sample size, inclusivity of different populations and measurements at different time points in pregnancy”, say the study authors.
They therefore set out to use a wider, more representative cohort to investigate DINCH and birth outcomes.
The phthalates that DINCH and other plasticisers are replacing have long been in the crosshairs of scientific scrutiny, especially around the effects of prenatal exposure. According to this recent study, “a large body of evidence has documented the effects of ortho-phthalates, additives to soft plastic used in food packaging, on premature birth”.
And according to the European Chemicals Agency, “several ortho-phthalates, for example DEHP, DBP, DIBP and BBP may damage fertility or the unborn baby and interfere with our hormonal system. In particular, they affect the sexual development of boys which can lead to infertility in adults. Apart from boys, pregnant women and young children in general have been found to be the most vulnerable groups to the effects of phthalates.”
What does it mean for manufacturers?
The chemicals in plastics are coming under increasing scrutiny for their effects on health. However, DINCH is approved for food contact by the European Food Safety Authority (EFSA) and in 2026, EFSA established a tolerable daily intake of 1 mg/kg bw/d for the plasticiser.
Further research that proves a causative effect would be needed before changes would need to be made, but manufacturers should be monitoring scientific developments closely.
The call by this study’s authors to investigate the combined effects of non-phthalate plasticisers follows similar calls on food contact chemicals such as bisphenols and phthalates. Studying them as groups, rather than individually, could help to understand their combined effects from different sources of exposure.
In May 2026, the US FDA released a scientific evaluation of eight ortho-phthalates to determine whether they should be grouped together for a cumulative risk assessment. “This work will inform the agency’s upcoming post-market safety assessment of the food contact uses of phthalates, which is part of the agency’s commitment to ensuring that chemicals in the US food supply remain safe as new scientific information becomes available,” says the FDA.
