Pick up a squishy bath toy marked 'phthalate-free' and it is natural to think the plastic question has been dealt with. But the label tells you which softener was left out, not which one went in.
When three phthalates were banned from toys and childcare articles, alternative substances and materials were brought in for those products instead.1 Two of the replacements are DINCH, which has been found in toys and childcare articles, and DEHTP, which is used especially in things made for sensitive groups, such as toys and medical devices.2,3,4
When researchers tested children and teenagers aged 3 to 17, they found DINCH breakdown products, what the body turns a chemical into before getting rid of it, in every one of them.5 Children aged 3 to 5 had almost 3 times the DINCH levels of adolescents aged 14 to 17.5
The levels found have mostly been well below health-based guidance values, the lines health advisers use as safe limits, but researchers say data on the health effects of DEHTP and DINCH, particularly in children, are currently lacking.6,7 YAN's view: a replacement is not proven safe just because it is not the chemical that was banned, so until there are long-term studies in children we would keep soft plastic out of small mouths where that is easy, without throwing out what you already own.
What you need to know
- The replacement softeners are not chemically bound to the plastic, so they can seep out into food, air and dust.7
- One study found DINCH levels in dust and urine higher than those reported in previous studies.6
- The free habits do the most: wash hands before meals and wipe dust with a damp cloth where children play.
What makes a soft toy soft
Soft PVC, often called vinyl, is a stiff plastic made bendy by mixing in a softener, called a plasticiser, and it is a common material for squeezy toys and bath toys.
DINCH, a softener for plastics, went on the world market in 2002 as a phthalate substitute.4 In one study that tested samples from different years, no DINCH breakdown products were detected in the 1999 and 2003 samples, but by 2012 they were measurable in 98% of samples.4 From 2013 on, researchers found OH-MINCH, one of DINCH's breakdown products, in every urine sample they analysed.5,8
How the softener reaches children
Researchers who sampled daycare centres found non-phthalate softeners, especially DINCH, in considerable amounts in the dust, and DINCH breakdown products in the children's urine.6 In the study of children aged 3 to 17, the more DINCH there was in the house dust, the higher the child's levels tended to be.5
That is why a toy's softener matters even if a child never chews it: some of it can end up in the dust on the floor where a baby crawls. Small children spend much of the day near the floor with their hands in their mouths, so dust and hands, not only the toy itself, are a likely route.
The rise is not limited to one country: in Japan, researchers found DEHTP and DINCH breakdown products in the great majority of the school children they tested.7 "Exposure levels to DEHTP and DINCH have increased considerably in Japanese school children," the researchers wrote.7 The researchers who studied the daycare centres expect more to come: "due to its increased use, higher exposure of DINCH is expected in the future."6
How worried should you be?
In one study the children's levels were hundreds of times or more below the guidance values set by German health advisers, and in another even the highest estimated exposures stayed below health-based guidance values.6,7 So most children tested sit far on the safe side of that line.
But in one study, a tiny share of children, 0.04%, went over the guidance value for DINCH.5 The researchers put it in proportion: "This finding shows that even a less toxic replacement of restricted chemicals can reach exposures in some individuals, at which, according to current knowledge, health impacts cannot be excluded with sufficient certainty."5 That cuts both ways: the banned phthalates were the worse option, and moving to a less toxic softener was a step forward, but a gentler chemical used everywhere still deserves a close watch in the children who meet the most of it.
In safety studies in rats and rabbits, DINCH showed no adverse effect on development.9 Another rat study found more bleeding in the testes of the offspring of pregnant rats dosed with DINCH.10 Animal studies like these use doses given directly to the animal, so they raise questions to answer rather than show harm in children.
In another lab study, scientists found no activity of DINCH itself, but one of its main breakdown products, MINCH, pushed cells to develop into fat cells.11 The report on that study pointed to a blind spot in routine safety testing as it stood then: "Current standard toxicological testing for food contact chemicals does not include assays for metabolic disruption, nor does it routinely ask for testing of a substance’s main metabolites."11 So the routine safety checks for chemicals that touch food would not have looked for the kind of effect this study found.
This investigation continues below.
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Who has checked, and what did they find?
So the researchers who track DINCH are asking for children to be watched closely while that answer comes in. "The ongoing increase in DINCH exposure needs to be closely monitored in the future, including populations with potentially higher exposures such as children," wrote one research team that tracked DINCH levels over the years.8
What nobody has checked yet
What would settle it for us is research that follows children who use these softeners over years. We would also want to know how these softeners add up with the phthalates children still take in. Most phthalate exposure comes from diet and personal care products.12
We don't read "below the guidance values" as an all-clear for a chemical nobody has followed in children, and we don't read the rat studies as proof of harm. Long-term studies in children showing no effect at today's levels would let us relax this advice; evidence of effects, or levels that keep climbing towards the guidance values, would make the case for cutting exposure stronger.
What to do, from free to stronger
Keep the toys you already have; nothing here calls for clearing out the toy box. Wash children's hands before they eat and after floor play, because the softener travels in dust. Damp-dust and vacuum the floor where small children play, which costs nothing but a little time.
Before buying a soft plastic toy, bath toy or teething item, one question to the seller helps: "What is used to soften this plastic?" When you buy for a baby or toddler, choose fewer squishy plastic things that will spend hours in a mouth.
For a teether, we prefer natural rubber to soft plastic because it comes from tree latex, not because tests show it releases less. Choose a teether whose pack or product page names EN 71-12, the part of Europe's toy-safety standard that tests rubber for chemicals left over from making it, and skip any with no maker's name. Offer other comforts too, so the teether isn't chewed for hours at a time. Give it loose, never on a cord, and skip natural rubber altogether if anyone at home has a latex allergy.
A teether made wholly of natural rubber can go in the home compost at the end of its life, though cured rubber is slow to break down.
Keep very old or second-hand soft plastic toys away from mouths, since they may date from before the phthalate bans. If you can't replace a soft plastic toy a child loves, let it stay for hands and the bath rather than the mouth.