For me, it has a picture where it specifies a “polypropylene container”.
There’s also this bit from near the end of the abstract:
Additionally, the polyethylene-based food pouch released more particles than polypropylene-based plastic containers. Exposure modeling results suggested that the highest estimated daily intake was 20.3 ng/kg·day for infants drinking microwaved water and 22.1 ng/kg·day for toddlers consuming microwaved dairy products from polypropylene containers.
So, they’re, at least, discussing polypropylene and polyethylene.
Materials and Property Characterization.
From a popular US chain store, two brands of baby food containers
made of polypropylene and one brand of reusable food pouch with-
out material information on the label were purchased. The selection
of polypropylene containers was based on its widespread use in baby
food packaging. These choices aimed to showcase diverse types of baby
food packaging.
The food containers and the food pouch were analyzed for their
semicrystalline structure and thermal stability by DSC using a Q200
differential scanning calorimeter (TA Instruments, New Castle, DE).
Briefly, a small sample weighing between 3 and 8 mg was taken from
each container or pouch, placed in a DSC aluminum pan/lid assem-
bly, and crimped with a press. The samples were heated and cooled at
a rate of 10 °C/min under a nitrogen atmosphere, resulting in calori-
metric curves that indicate the heat transfer to and from the polymer
sample during the thermal cycle, which was used to monitor phase
transitions.
H u s s a i n e t a l . i n E n v i r o n . S c i . T e c h n o l . 5 7 ( 2 0 2 3 ) 5
Transmission wide-angle X-ray diffraction (WAXD) of the reusable
food pouch was performed at the 12-ID-B beamline at the Advanced Pho-
ton Source (Argonne National Laboratory), using incident X-rays with
energy 13.30 keV and a Pilatus 300k 2D detector mounted 0.4 m from
the sample. WAXD patterns of the two plastic containers were acquired
in reflection geometry with a Bruker-AXS D8 Discover equipped with a
Cu Kα lab source (λ = 1.5406 A) and a Vantec 500 area detector. In all
cases, the acquired 2D patterns were radially averaged to produce 1D
intensity (I) vs scattering vector (q) plots
two brands of baby food containers made of polypropylene and one brand of reusable food pouch
These choices aimed to showcase diverse types of baby food packaging
3 brands, two of the same overall declared material, and no reference to manufacturer formulation safety data. If this is an American paper, the FDA requires substances that come into contact with food to be vetted, so the information should exist somewhere if these are legally sold. Which is obviously not guaranteed. This is not giving me much hope for this study.
Here’s the study in question. Can’t speak to the authenticity of it but off the top I don’t see anything shady
It doesn’t look shady, but I can only access the abstract which just says “plastics” and doesn’t specify that part further, unfortunately.
For me, it has a picture where it specifies a “polypropylene container”.
There’s also this bit from near the end of the abstract:
So, they’re, at least, discussing polypropylene and polyethylene.
From the method section of the paper:
Materials and Property Characterization. From a popular US chain store, two brands of baby food containers made of polypropylene and one brand of reusable food pouch with- out material information on the label were purchased. The selection of polypropylene containers was based on its widespread use in baby food packaging. These choices aimed to showcase diverse types of baby food packaging. The food containers and the food pouch were analyzed for their semicrystalline structure and thermal stability by DSC using a Q200 differential scanning calorimeter (TA Instruments, New Castle, DE). Briefly, a small sample weighing between 3 and 8 mg was taken from each container or pouch, placed in a DSC aluminum pan/lid assem- bly, and crimped with a press. The samples were heated and cooled at a rate of 10 °C/min under a nitrogen atmosphere, resulting in calori- metric curves that indicate the heat transfer to and from the polymer sample during the thermal cycle, which was used to monitor phase transitions. H u s s a i n e t a l . i n E n v i r o n . S c i . T e c h n o l . 5 7 ( 2 0 2 3 ) 5 Transmission wide-angle X-ray diffraction (WAXD) of the reusable food pouch was performed at the 12-ID-B beamline at the Advanced Pho- ton Source (Argonne National Laboratory), using incident X-rays with energy 13.30 keV and a Pilatus 300k 2D detector mounted 0.4 m from the sample. WAXD patterns of the two plastic containers were acquired in reflection geometry with a Bruker-AXS D8 Discover equipped with a Cu Kα lab source (λ = 1.5406 A) and a Vantec 500 area detector. In all cases, the acquired 2D patterns were radially averaged to produce 1D intensity (I) vs scattering vector (q) plots
3 brands, two of the same overall declared material, and no reference to manufacturer formulation safety data. If this is an American paper, the FDA requires substances that come into contact with food to be vetted, so the information should exist somewhere if these are legally sold. Which is obviously not guaranteed. This is not giving me much hope for this study.