The same may be true for maple syrup, corn
syrup and others according to some sources. This would only be a risk if it were real maple
syrup. Most of the stuff in the grocery store is sugar with other colorings and flavorings. Babies do not need that sugar!
Rice cereal has no real nutritional value, so it isn't something a 4 month old would need to begin with. As long as baby is getting enough breastmilk or formula, it wouldn't even matter that the baby won't eat the cereal.