Is Polyethylene safe in food and drink?

Heating polyethylene, particularly at high temperatures such as those found in a microwave, can cause the material to deform and potentially release decomposition products or leach plastic additives into food.

Why here

The physical properties of polyethylene change with heat, leading to degradation and increased migration of substances into contacting food or beverages.

What would have to be true

Ingestion of food or beverages heated in polyethylene containers not explicitly marked as microwave-safe, or when boiling water is poured directly into thin-walled polyethylene products.

The other side

N/A.

While pure polyethylene resin may not leach endocrine-disrupting chemicals, studies have shown that common food containers made with polyethylene can leach plastic additives, with leaching increasing with heat, duration of contact, and acidity of the food or drink.

Why here

Additives are incorporated into polyethylene during manufacturing to achieve desired properties, and these can migrate out of the plastic and into food, especially under conditions that promote degradation or migration.

What would have to be true

Ingestion of food or beverages that have been in contact with polyethylene food containers, particularly when exposed to heat, prolonged contact, or acidic contents.

The other side

Food-grade HDPE uses tightly controlled additives that meet regulatory standards, and independent studies confirm that virgin HDPE meeting these standards does not produce migration levels of concern under typical food-contact conditions (room temperature to 70 degrees C, contact time up to 30 days).

Ingested polyethylene microplastics (PE-MPs) have been detected in human biological matrices, and studies in animal models and human cell lines suggest chronic exposure is associated with potential health effects such as oxidative stress, inflammation, metabolic dysregulation, immune system modulation, and interference with endocrine and neurological systems.

Why here

Polyethylene, especially from single-use packaging, degrades into microplastics that enter the food chain and are ingested by humans through contaminated food and water, accumulating in various organs.

What would have to be true

Ingestion of food (e.g., seafood, salt, sugar, honey, bottled water) and drinking water contaminated with polyethylene microplastics, with adults estimated to ingest the equivalent of one credit card per week in microplastics.

The other side

Long-term human epidemiological studies are limited, and the exact toxicity and definitive exposure levels for human health impacts are still being researched.

Food-grade polyethylene, including high-density polyethylene (HDPE) and low-density polyethylene (LDPE), is generally considered safe for direct food contact and is approved by regulatory bodies like the FDA for use in food packaging and containers under normal conditions.

Why here

Polyethylene is widely used in food packaging due to its chemical inertness, which prevents it from reacting with or leaching harmful chemicals into food when used as intended.

What would have to be true

Ingestion of food or beverages stored in food-grade polyethylene containers at room or cold temperatures.

The other side

N/A.

Ingestion of polyethylene microplastics is linked in studies to adverse effects on cells, including decreased cell viability and increased production of reactive oxygen species in human colorectal cancer cell lines, and can carry harmful chemicals that may interfere with hormone function, increase inflammation, or raise the risk of certain diseases in children.

Why here

Children are particularly vulnerable to microplastic exposure due to higher intake-to-body-weight ratios, developing bodies, and behaviors like frequent hand-to-mouth activities, with exposure occurring through diet, water, air, and plastic products; heating polyethylene-containing food containers can increase the migration of microplastics and associated chemicals into food.

What would have to be true

Chronic ingestion of polyethylene microplastics and associated chemicals from food, water, and contact with plastic products, especially when heated.

The other side

The American Chemistry Council states that detecting microplastics does not necessarily mean a health risk, and the World Health Organization found no reliable evidence to suggest ingesting microplastic particles through drinking water is a concern.