Baby Poop Smells Like Chemicals

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Baby Poop Smells Like Chemicals

If the poop is in the intestines for a long time, the smell is a reflection of that. For as long as the poop sits in bacteria, the worse the smell will be. Occasionally, babies whose poop has a very sour or foul smell may be suffering from food intolerances or allergies. All this can lead up to a situation where baby poop smells like chemicals.

The poop of a breastfed infant does not stink generally, while a formula-fed infant poop can have some slight odor. It might happen that formula milk is not soothing your baby and result in some difficulties of the baby digesting the food. In that case, parents should change to formula and see how the baby will react to it. Try to find the one that suits your baby’s stomach the best.

However, once you introduce solid foods to your baby along with different types of fruits and vegetables, the bad odor of the baby poop will be pretty common. You should also have in mind that if the bowel movements of your baby seem unusually smelly, it is best to consult your baby’s pediatrician.

Between the ages of 4 and 6 months, your baby will start eating solid food and the schedule of their bowel movements will change. In addition to having fewer stools, the stools themselves will become thicker.

Some foods will go indigestible which is normal since babies have trouble chewing their food, as well as quickly absorbing nutrients through their digestive tract.

Your little one will start eating a different range of food by the age of one so there is a possibility for poop to change again. Depending on what your child has eaten will affect the consistency of the poop.

Sometimes it will be thicker, it will smell different and the color will change as well. As time is passing by, the poop will get browner, thicker, and look more like adult poop.

What does metallic smelling poop mean?

This means that your baby might have high numbers of sulfur that produce bacteria in your baby’s gut. The other reasons might be because of the presence of iron supplements or even having some blood in the gut. At this point, the poop will be black pretty often with a sticky consistency. 

The diet plays an important role in the smell of the baby’s stool. If you give your child some fatty or greasy foods, the baby can end up with foul-smelling gas but most often if it ends up with a metallic smell of a stool. This odor can also be from some supplements or diet pills that your baby is getting.

Since many vitamin pills contain preservatives and color dyes, this metallic smell may occur as a side effect. For instance, vitamin B is pretty known for causing this side effect.

Overall, we don’t recommend giving those supplements to your baby on your own. If your baby is lacking some vitamins, just make sure that the health care provider confirms it and prescribes the right medications. 

When should I worry about baby poop smell?

Baby Poop Smells Like Chemicals

It is normal for poop to have a certain odor. As long as your baby has normal and frequent bowel movements and the poop is soft inconsistency, there’s no need to worry about its smell.

If changes happen, like if stool becomes more loose and green, and the smell starts to be unbearable it’s time to make an appointment with your infant’s health provider for a check-up. 

In these cases, there is a big possibility that your baby has some type of allergies related to some food or ingredients, or just developed intolerance towards certain foods. 

For a few days, you may not smell anything in your infant’s stool. Even after passing meconium, some parents report that their breastfed infant’s poop still smells good. As a matter of fact, it may smell slightly sweet. The smell of your baby’s stool isn’t usually a concern as long as they have frequent bowel movements.

What does concerning baby poop look like?

Baby Poop Smells Like Chemicals

If your baby is breastfed its poop will be yellow or even slightly green, and when it comes to the consistency it’s usually creamy and mushy. Sometimes it will be runny enough to be reminiscent of diarrhea. Those babies who are breastfed have poop that looks like a mustard color and sometimes is flecked with tiny seeds.

The colors of baby stool can fluctuate. Overall color and consistency can also be affected by the baby’s age and its feeding.

If you are having concerns about the look and the smell of a baby’s stool, the best thing to do is contact the baby’s pediatrician. Sometimes fever and diarrhea can be signs for taking your baby to an examination.  

If your baby is struggling with incredibly hard and dry stools that is probably a sign of constipation. On the other hand, if your baby vomits or is ill in some other way, it might be that your baby is dehydrated. Other symptoms of dehydration are fewer diaper changes, fussiness, crying without tears, fatigue, and exhaustion, etc.


If your baby poop smells like chemicals that are probably the result of poop being in the infant’s intestines for a longer time then it should be. Sometimes the poop can have a bad, sour smell that is usually caused by a baby’s intolerances or allergies to certain food.

In the earliest stage of a baby’s life, the newborns who are breastfed do not have a smelly poop so often. On the other hand, infants that are bottle-fed usually end up with stinky poop. This probably means that the formula the parents are using to feed the baby is not soothing her or him. 

In that case, try to change it and see how the baby and its stomach are going to react. If the odor is still present, and somewhat unbearable, make sure to take your baby to visit a doctor to check that everything is in the right order. 

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My name is Catherine. I'm a Mom and one of the avid writers working on HerScoop!