"questionable ingredients" is a correct and usable phrase in written English.
It is typically used to describe ingredients that someone may have doubts or concerns about, such as their safety, ethics, or source. Example: The new health food product claims to be all natural, but upon closer inspection, I noticed a list of questionable ingredients that made me question its authenticity.
Mark Bittman writes that there are "questionable ingredients" in cosmetics, "many of which haven't been tested".
Environmental and consumer groups have for years pressured Johnson & Johnson and its competitors to remove questionable ingredients from their products.
Using questionable ingredients may be in the interest of manufacturers, but it certainly isn't in the interests of consumers.
Yes, the dough is a crucial ingredient; but there are other crucial ingredients, and very questionable ingredients at that.
Because although there may be less animal testing of personal care products than there once was — even here in the United States — and many manufacturers have found new ways of determining that products are "safe," there are still plenty of questionable ingredients in your bubble bath, many of which haven't been tested by any means at all.
"Most consumers of feminine hygiene products have almost invariably only been exposed to disposable products, and brand loyalty is entrenched at an early age," says Shaw. "Most consumers are also unaware of questionable ingredients in disposable products, or even the fact that manufacturers are not legally required to disclose ingredients in the first place".
And, instead of withholding a questionable ingredient list, wall signs waxed poetic about the health benefits of probiotics.
Consistent with that narrative, the article asserted that big corporations were compromising the organic label by lobbying for questionable "synthetic" ingredients in organic food.
Question questionable sources.
However, the idea of adding often claggy, chunky hummus to a thick, sliced bread sandwich of turkey or chicken (how dry would that be?) or, for the non-meat eaters, using it as a major sandwich filling in endless combinations of avocado, tomatoes, egg, spicy carrot and feta, seems not just gastronomically questionable – how well do those ingredients gel, really?
First of all, the front label "reduced calorie" or "reduced sugar" disclosures have always been prominent and useful tip-offs to purchasers that a product may contain artificial sweeteners or other artificial ingredients that many find questionable.
