In 2018, over 400 million metric tonnes of plastics were manufactured across the globe.
60% of this manufactured plastic was supplied to food and beverage industry for packaging and other uses.
Exposure of plastic to food and beverages can be primary or secondary.
In primary exposure, plastic can be added by the manufacturer as stabilisers, fillers or lubricants. This accounts for about 10% exposure of plastic to food and beverage.
In secondary exposure which accounts for about 90%, heat and other environmental conditions during storage and transportation can cause plastic break into small particles or microplastics. These can go to food and beverage directly. Single use water bottles and food cans are the most common conduits of plastic exposure to food.
With the ubiquitous distribution of plastic into natural habitats of wildlife, water bodies and arable soils; some of these microplastics have found their way into our food chain.
An average adult consumes approximately 90,000 microplastics annually.
While most microplastics are thought to be biologically inert, there are some particles of concern. Those that have been found to be biologically active in the human body. Some of the biological activity includes:
1. A pregnant mother can transmit microplastics to her unborn child.
2. Biologically active microplastics mimic and disrupt hormones.
For example Bisphenol A, a common plasticizer in PVC disrupts Male and Female hormones, has been found involved in the propagation of secondary infertility and polycystic ovarian syndrome.
Long-term exposure to other endocrine disrupting compounds(EDCs) have been found to cause diabetes, hypertension, heart disease and influence growth of some cancers.
Read more about another article on EDCs.
Vinyl chrolide (VC) a monomer of PVC is a well known human carcinogen implicated in various cancers of the lungs and liver.
3. Immune system disruption.
The digestive tract contains various tissues and cells that constitute 70% to 80% of the body's immune system. Microplastics disrupt digestive tract microbiota compromising the immune system of the gut.
4. Microplastics cause inflammatory diseases of the respiratory tract. Some of the conditions associated with microplastics have been found to result into Non-small cell lung cancers.
Body toxicities from plastics happen through mechanisms below.
A. Oxidative stress and generation of reactive species (Free radicals) that damage cells and tissues.
B. Free radicals can cause series of inflammatory lesions and these can progress to cancer.
C. Microplastics can cause DNA damage to the cells. These can still progress to cancer if not eliminated by the body's immune system mechanisms.
D. Normal body functions of metabolism can be disrupted by free radicals and oxidative stress.
How can you minimize exposure to microplastics and their effects.
1. Reduce consumption of industrially processed foods and beverages.
2. Choose eco-friendly food packaging eg glass storage containers, stainless steel containers and bamboo/wood containers.
3. Have an abundant supply of antioxidants and phytonutirents to counter and neutralize free radicals and their effects.
Click the link to see antioxidant recommendations.